kafka-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From jkr...@apache.org
Subject svn commit: r1659720 [8/18] - in /kafka/site/083: ./ javadoc/ javadoc/org/ javadoc/org/apache/ javadoc/org/apache/kafka/ javadoc/org/apache/kafka/clients/ javadoc/org/apache/kafka/clients/consumer/ javadoc/org/apache/kafka/clients/producer/ javadoc/org...
Date Fri, 13 Feb 2015 23:54:01 GMT
Added: kafka/site/083/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html
URL: http://svn.apache.org/viewvc/kafka/site/083/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html?rev=1659720&view=auto
==============================================================================
--- kafka/site/083/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html (added)
+++ kafka/site/083/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html Fri Feb 13 23:54:00 2015
@@ -0,0 +1,1002 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<!-- NewPage -->
+<html lang="en">
+<head>
+<!-- Generated by javadoc (version 1.7.0_51) on Fri Feb 13 15:47:44 PST 2015 -->
+<title>KafkaConsumer (clients 0.8.3-SNAPSHOT API)</title>
+<meta name="date" content="2015-02-13">
+<link rel="stylesheet" type="text/css" href="../../../../../stylesheet.css" title="Style">
+</head>
+<body>
+<script type="text/javascript"><!--
+    if (location.href.indexOf('is-external=true') == -1) {
+        parent.document.title="KafkaConsumer (clients 0.8.3-SNAPSHOT API)";
+    }
+//-->
+</script>
+<noscript>
+<div>JavaScript is disabled on your browser.</div>
+</noscript>
+<!-- ========= START OF TOP NAVBAR ======= -->
+<div class="topNav"><a name="navbar_top">
+<!--   -->
+</a><a href="#skip-navbar_top" title="Skip navigation links"></a><a name="navbar_top_firstrow">
+<!--   -->
+</a>
+<ul class="navList" title="Navigation">
+<li><a href="../../../../../overview-summary.html">Overview</a></li>
+<li><a href="package-summary.html">Package</a></li>
+<li class="navBarCell1Rev">Class</li>
+<li><a href="package-tree.html">Tree</a></li>
+<li><a href="../../../../../deprecated-list.html">Deprecated</a></li>
+<li><a href="../../../../../index-all.html">Index</a></li>
+<li><a href="../../../../../help-doc.html">Help</a></li>
+</ul>
+</div>
+<div class="subNav">
+<ul class="navList">
+<li><a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecords.html" title="class in org.apache.kafka.clients.consumer"><span class="strong">Prev Class</span></a></li>
+<li><a href="../../../../../org/apache/kafka/clients/consumer/MockConsumer.html" title="class in org.apache.kafka.clients.consumer"><span class="strong">Next Class</span></a></li>
+</ul>
+<ul class="navList">
+<li><a href="../../../../../index.html?org/apache/kafka/clients/consumer/KafkaConsumer.html" target="_top">Frames</a></li>
+<li><a href="KafkaConsumer.html" target="_top">No Frames</a></li>
+</ul>
+<ul class="navList" id="allclasses_navbar_top">
+<li><a href="../../../../../allclasses-noframe.html">All Classes</a></li>
+</ul>
+<div>
+<script type="text/javascript"><!--
+  allClassesLink = document.getElementById("allclasses_navbar_top");
+  if(window==top) {
+    allClassesLink.style.display = "block";
+  }
+  else {
+    allClassesLink.style.display = "none";
+  }
+  //-->
+</script>
+</div>
+<div>
+<ul class="subNavList">
+<li>Summary:&nbsp;</li>
+<li>Nested&nbsp;|&nbsp;</li>
+<li>Field&nbsp;|&nbsp;</li>
+<li><a href="#constructor_summary">Constr</a>&nbsp;|&nbsp;</li>
+<li><a href="#method_summary">Method</a></li>
+</ul>
+<ul class="subNavList">
+<li>Detail:&nbsp;</li>
+<li>Field&nbsp;|&nbsp;</li>
+<li><a href="#constructor_detail">Constr</a>&nbsp;|&nbsp;</li>
+<li><a href="#method_detail">Method</a></li>
+</ul>
+</div>
+<a name="skip-navbar_top">
+<!--   -->
+</a></div>
+<!-- ========= END OF TOP NAVBAR ========= -->
+<!-- ======== START OF CLASS DATA ======== -->
+<div class="header">
+<div class="subTitle">org.apache.kafka.clients.consumer</div>
+<h2 title="Class KafkaConsumer" class="title">Class KafkaConsumer&lt;K,V&gt;</h2>
+</div>
+<div class="contentContainer">
+<ul class="inheritance">
+<li>java.lang.Object</li>
+<li>
+<ul class="inheritance">
+<li>org.apache.kafka.clients.consumer.KafkaConsumer&lt;K,V&gt;</li>
+</ul>
+</li>
+</ul>
+<div class="description">
+<ul class="blockList">
+<li class="blockList">
+<dl>
+<dt>All Implemented Interfaces:</dt>
+<dd>java.io.Closeable, java.lang.AutoCloseable, <a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;K,V&gt;</dd>
+</dl>
+<hr>
+<br>
+<pre>public class <span class="strong">KafkaConsumer&lt;K,V&gt;</span>
+extends java.lang.Object
+implements <a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;K,V&gt;</pre>
+<div class="block">A Kafka client that consumes records from a Kafka cluster.
+ <p>
+ It will transparently handle the failure of servers in the Kafka cluster, and transparently adapt as partitions of
+ data it subscribes to migrate within the cluster. This client also interacts with the server to allow groups of
+ consumers to load balance consumption using consumer groups (as described below).
+ <p>
+ The consumer maintains TCP connections to the necessary brokers to fetch data for the topics it subscribes to.
+ Failure to close the consumer after use will leak these connections.
+ <p>
+ The consumer is thread safe but generally will be used only from within a single thread. The consumer client has no
+ threads of it's own, all work is done in the caller's thread when calls are made on the various methods exposed.
+ 
+ <h3>Offsets and Consumer Position</h3>
+ Kafka maintains a numerical offset for each record in a partition. This offset acts as a kind of unique identifier of
+ a record within that partition, and also denotes the position of the consumer in the partition. That is, a consumer
+ which has position 5 has consumed records with offsets 0 through 4 and will next receive record with offset 5. There
+ are actually two notions of position relevant to the user of the consumer.
+ <p>
+ The <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#position(org.apache.kafka.common.TopicPartition)"><code>position</code></a> of the consumer gives the offset of the next record that will be given
+ out. It will be one larger than the highest offset the consumer has seen in that partition. It automatically advances
+ every time the consumer receives data calls <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll(long)</code></a> and receives messages.
+ <p>
+ The <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(org.apache.kafka.clients.consumer.CommitType)"><code>committed position</code></a> is the last offset that has been saved securely. Should the
+ process fail and restart, this is the offset that it will recover to. The consumer can either automatically commit
+ offsets periodically, or it can choose to control this committed position manually by calling
+ <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(org.apache.kafka.clients.consumer.CommitType)"><code>commit</code></a>.
+ <p>
+ This distinction gives the consumer control over when a record is considered consumed. It is discussed in further
+ detail below.
+ 
+ <h3>Consumer Groups</h3>
+ 
+ Kafka uses the concept of <i>consumer groups</i> to allow a pool of processes to divide up the work of consuming and
+ processing records. These processes can either be running on the same machine or, as is more likely, they can be
+ distributed over many machines to provide additional scalability and fault tolerance for processing.
+ <p>
+ Each Kafka consumer must specify a consumer group that it belongs to. Kafka will deliver each message in the
+ subscribed topics to one process in each consumer group. This is achieved by balancing the partitions in the topic
+ over the consumer processes in each group. So if there is a topic with four partitions, and a consumer group with two
+ processes, each process would consume from two partitions. This group membership is maintained dynamically: if a
+ process fails the partitions assigned to it will be reassigned to other processes in the same group, and if a new
+ process joins the group, partitions will be moved from existing consumers to this new process.
+ <p>
+ So if two processes subscribe to a topic both specifying different groups they will each get all the records in that
+ topic; if they both specify the same group they will each get about half the records.
+ <p>
+ Conceptually you can think of a consumer group as being a single logical subscriber that happens to be made up of
+ multiple processes. As a multi-subscriber system, Kafka naturally supports having any number of consumer groups for a
+ given topic without duplicating data (additional consumers are actually quite cheap).
+ <p>
+ This is a slight generalization of the functionality that is common in messaging systems. To get semantics similar to
+ a queue in a traditional messaging system all processes would be part of a single consumer group and hence record
+ delivery would be balanced over the group like with a queue. Unlike a traditional messaging system, though, you can
+ have multiple such groups. To get semantics similar to pub-sub in a traditional messaging system each process would
+ have it's own consumer group, so each process would subscribe to all the records published to the topic.
+ <p>
+ In addition, when offsets are committed they are always committed for a given consumer group.
+ <p>
+ It is also possible for the consumer to manually specify the partitions it subscribes to, which disables this dynamic
+ partition balancing.
+ 
+ <h3>Usage Examples</h3>
+ The consumer APIs offer flexibility to cover a variety of consumption use cases. Here are some examples to
+ demonstrate how to use them.
+ 
+ <h4>Simple Processing</h4>
+ This example demonstrates the simplest usage of Kafka's consumer api.
+ 
+ <pre>
+     Properties props = new Properties();
+     props.put(&quot;metadata.broker.list&quot;, &quot;localhost:9092&quot;);
+     props.put(&quot;group.id&quot;, &quot;test&quot;);
+     props.put(&quot;enable.auto.commit&quot;, &quot;true&quot;);
+     props.put(&quot;auto.commit.interval.ms&quot;, &quot;1000&quot;);
+     props.put(&quot;session.timeout.ms&quot;, &quot;30000&quot;);
+     props.put(&quot;key.serializer&quot;, &quot;org.apache.kafka.common.serializers.StringSerializer&quot;);
+     props.put(&quot;value.serializer&quot;, &quot;org.apache.kafka.common.serializers.StringSerializer&quot;);
+     KafkaConsumer&lt;String, String&gt; consumer = new KafkaConsumer&lt;String, String&gt;(props);
+     consumer.subscribe(&quot;foo&quot;, &quot;bar&quot;);
+     while (true) {
+         ConsumerRecords&lt;String, String&gt; records = consumer.poll(100);
+         for (ConsumerRecord&lt;String, String&gt; record : records)
+             System.out.printf(&quot;offset = %d, key = %s, value = %s&quot;, record.offset(), record.key(), record.value());
+     }
+ </pre>
+ 
+ Setting <code>enable.auto.commit</code> means that offsets are committed automatically with a frequency controlled by
+ the config <code>auto.commit.interval.ms</code>.
+ <p>
+ The connection to the cluster is bootstrapped by specifying a list of one or more brokers to contact using the
+ configuration <code>metadata.broker.list</code>. This list is just used to discover the rest of the brokers in the
+ cluster and need not be an exhaustive list of servers in the cluster (though you may want to specify more than one in
+ case there are servers down when the client is connecting).
+ <p>
+ In this example the client is subscribing to the topics <i>foo</i> and <i>bar</i> as part of a group of consumers
+ called <i>test</i> as described above.
+ <p>
+ The broker will automatically detect failed processes in the <i>test</i> group by using a heartbeat mechanism. The
+ consumer will automatically ping the cluster periodically, which let's the cluster know that it is alive. As long as
+ the consumer is able to do this it is considered alive and retains the right to consume from the partitions assigned
+ to it. If it stops heartbeating for a period of time longer than <code>session.timeout.ms</code> then it will be
+ considered dead and it's partitions will be assigned to another process.
+ <p>
+ The serializers settings specify how to turn the objects the user provides into bytes. By specifying the string
+ serializers we are saying that our record's key and value will just be simple strings.
+ 
+ <h4>Controlling When Messages Are Considered Consumed</h4>
+ 
+ In this example we will consume a batch of records and batch them up in memory, when we have sufficient records
+ batched we will insert them into a database. If we allowed offsets to auto commit as in the previous example messages
+ would be considered consumed after they were given out by the consumer, and it would be possible that our process
+ could fail after we have read messages into our in-memory buffer but before they had been inserted into the database.
+ To avoid this we will manually commit the offsets only once the corresponding messages have been inserted into the
+ database. This gives us exact control of when a message is considered consumed. This raises the opposite possibility:
+ the process could fail in the interval after the insert into the database but before the commit (even though this
+ would likely just be a few milliseconds, it is a possibility). In this case the process that took over consumption
+ would consume from last committed offset and would repeat the insert of the last batch of data. Used in this way
+ Kafka provides what is often called "at-least once delivery" guarantees, as each message will likely be delivered one
+ time but in failure cases could be duplicated.
+ 
+ <pre>
+     Properties props = new Properties();
+     props.put(&quot;metadata.broker.list&quot;, &quot;localhost:9092&quot;);
+     props.put(&quot;group.id&quot;, &quot;test&quot;);
+     props.put(&quot;enable.auto.commit&quot;, &quot;false&quot;);
+     props.put(&quot;auto.commit.interval.ms&quot;, &quot;1000&quot;);
+     props.put(&quot;session.timeout.ms&quot;, &quot;30000&quot;);
+     props.put(&quot;key.serializer&quot;, &quot;org.apache.kafka.common.serializers.StringSerializer&quot;);
+     props.put(&quot;value.serializer&quot;, &quot;org.apache.kafka.common.serializers.StringSerializer&quot;);
+     KafkaConsumer&lt;String, String&gt; consumer = new KafkaConsumer&lt;String, String&gt;(props);
+     consumer.subscribe(&quot;foo&quot;, &quot;bar&quot;);
+     int commitInterval = 200;
+     List&lt;ConsumerRecord&lt;String, String&gt;&gt; buffer = new ArrayList&lt;ConsumerRecord&lt;String, String&gt;&gt;();
+     while (true) {
+         ConsumerRecords&lt;String, String&gt; records = consumer.poll(100);
+         for (ConsumerRecord&lt;String, String&gt; record : records) {
+             buffer.add(record);
+             if (buffer.size() &gt;= commitInterval) {
+                 insertIntoDb(buffer);
+                 consumer.commit(CommitType.SYNC);
+                 buffer.clear();
+             }
+         }
+     }
+ </pre>
+ 
+ <h4>Subscribing To Specific Partitions</h4>
+ 
+ In the previous examples we subscribed to the topics we were interested in and let Kafka give our particular process
+ a fair share of the partitions for those topics. This provides a simple load balancing mechanism so multiple
+ instances of our program can divided up the work of processing records.
+ <p>
+ In this mode the consumer will just get the partitions it subscribes to and if the consumer instance fails no attempt
+ will be made to rebalance partitions to other instances.
+ <p>
+ There are several cases where this makes sense:
+ <ul>
+ <li>The first case is if the process is maintaining some kind of local state associated with that partition (like a
+ local on-disk key-value store) and hence it should only get records for the partition it is maintaining on disk.
+ <li>Another case is if the process itself is highly available and will be restarted if it fails (perhaps using a
+ cluster management framework like YARN, Mesos, or AWS facilities, or as part of a stream processing framework). In
+ this case there is no need for Kafka to detect the failure and reassign the partition, rather the consuming process
+ will be restarted on another machine.
+ </ul>
+ <p>
+ This mode is easy to specify, rather than subscribing to the topic, the consumer just subscribes to particular
+ partitions:
+ 
+ <pre>
+     String topic = &quot;foo&quot;;
+     TopicPartition partition0 = new TopicPartition(topic, 0);
+     TopicPartition partition1 = new TopicPartition(topic, 1);
+     consumer.subscribe(partition0);
+     consumer.subscribe(partition1);
+ </pre>
+ 
+ The group that the consumer specifies is still used for committing offsets, but now the set of partitions will only
+ be changed if the consumer specifies new partitions, and no attempt at failure detection will be made.
+ <p>
+ It isn't possible to mix both subscription to specific partitions (with no load balancing) and to topics (with load
+ balancing) using the same consumer instance.
+ 
+ <h4>Managing Your Own Offsets</h4>
+ 
+ The consumer application need not use Kafka's built-in offset storage, it can store offsets in a store of it's own
+ choosing. The primary use case for this is allowing the application to store both the offset and the results of the
+ consumption in the same system in a way that both the results and offsets are stored atomically. This is not always
+ possible, but when it is it will make the consumption fully atomic and give "exactly once" semantics that are
+ stronger than the default "at-least once" semantics you get with Kafka's offset commit functionality.
+ <p>
+ Here are a couple of examples of this type of usage:
+ <ul>
+ <li>If the results of the consumption are being stored in a relational database, storing the offset in the database
+ as well can allow committing both the results and offset in a single transaction. Thus either the transaction will
+ succeed and the offset will be updated based on what was consumed or the result will not be stored and the offset
+ won't be updated.
+ <li>If the results are being stored in a local store it may be possible to store the offset there as well. For
+ example a search index could be built by subscribing to a particular partition and storing both the offset and the
+ indexed data together. If this is done in a way that is atomic, it is often possible to have it be the case that even
+ if a crash occurs that causes unsync'd data to be lost, whatever is left has the corresponding offset stored as well.
+ This means that in this case the indexing process that comes back having lost recent updates just resumes indexing
+ from what it has ensuring that no updates are lost.
+ </ul>
+ 
+ Each record comes with it's own offset, so to manage your own offset you just need to do the following:
+ <ol>
+ <li>Configure <code>enable.auto.commit=false</code>
+ <li>Use the offset provided with each <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecord.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerRecord</code></a> to save your position.
+ <li>On restart restore the position of the consumer using <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)"><code>seek(TopicPartition, long)</code></a>.
+ </ol>
+ 
+ This type of usage is simplest when the partition assignment is also done manually (this would be likely in the
+ search index use case described above). If the partition assignment is done automatically special care will also be
+ needed to handle the case where partition assignments change. This can be handled using a special callback specified
+ using <code>rebalance.callback.class</code>, which specifies an implementation of the interface
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a>. When partitions are taken from a consumer the consumer will want to commit its
+ offset for those partitions by implementing
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html#onPartitionsRevoked(org.apache.kafka.clients.consumer.Consumer, java.util.Collection)"><code>ConsumerRebalanceCallback.onPartitionsRevoked(Consumer, Collection)</code></a>. When partitions are assigned to a
+ consumer, the consumer will want to look up the offset for those new partitions an correctly initialize the consumer
+ to that position by implementing <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html#onPartitionsAssigned(org.apache.kafka.clients.consumer.Consumer, java.util.Collection)"><code>ConsumerRebalanceCallback.onPartitionsAssigned(Consumer, Collection)</code></a>.
+ <p>
+ Another common use for <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a> is to flush any caches the application maintains for
+ partitions that are moved elsewhere.
+ 
+ <h4>Controlling The Consumer's Position</h4>
+ 
+ In most use cases the consumer will simply consume records from beginning to end, periodically committing it's
+ position (either automatically or manually). However Kafka allows the consumer to manually control it's position,
+ moving forward or backwards in a partition at will. This means a consumer can re-consume older records, or skip to
+ the most recent records without actually consuming the intermediate records.
+ <p>
+ There are several instances where manually controlling the consumer's position can be useful.
+ <p>
+ One case is for time-sensitive record processing it may make sense for a consumer that falls far enough behind to not
+ attempt to catch up processing all records, but rather just skip to the most recent records.
+ <p>
+ Another use case is for a system that maintains local state as described in the previous section. In such a system
+ the consumer will want to initialize it's position on start-up to whatever is contained in the local store. Likewise
+ if the local state is destroyed (say because the disk is lost) the state may be recreated on a new machine by
+ reconsuming all the data and recreating the state (assuming that Kafka is retaining sufficient history).
+ 
+ Kafka allows specifying the position using <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)"><code>seek(TopicPartition, long)</code></a> to specify the new position. Special
+ methods for seeking to the earliest and latest offset the server maintains are also available (
+ <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToBeginning(org.apache.kafka.common.TopicPartition...)"><code>seekToBeginning(TopicPartition...)</code></a> and <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToEnd(org.apache.kafka.common.TopicPartition...)"><code>seekToEnd(TopicPartition...)</code></a> respectively).
+ 
+ <h3>Multithreaded Processing</h3>
+ 
+ The Kafka consumer is threadsafe but coarsely synchronized. All network I/O happens in the thread of the application
+ making the call. We have intentionally avoided implementing a particular threading model for processing.
+ <p>
+ This leaves several options for implementing multi-threaded processing of records.
+ 
+ <h4>1. One Consumer Per Thread</h4>
+ 
+ A simple option is to give each thread it's own consumer instance. Here are the pros and cons of this approach:
+ <ul>
+ <li><b>PRO</b>: It is the easiest to implement
+ <li><b>PRO</b>: It is often the fastest as no inter-thread co-ordination is needed
+ <li><b>PRO</b>: It makes in-order processing on a per-partition basis very easy to implement (each thread just
+ processes messages in the order it receives them).
+ <li><b>CON</b>: More consumers means more TCP connections to the cluster (one per thread). In general Kafka handles
+ connections very efficiently so this is generally a small cost.
+ <li><b>CON</b>: Multiple consumers means more requests being sent to the server and slightly less batching of data
+ which can cause some drop in I/O throughput.
+ <li><b>CON</b>: The number of total threads across all processes will be limited by the total number of partitions.
+ </ul>
+ 
+ <h4>2. Decouple Consumption and Processing</h4>
+ 
+ Another alternative is to have one or more consumer threads that do all data consumption and hands off
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecords.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerRecords</code></a> instances to a blocking queue consumed by a pool of processor threads that actually handle
+ the record processing.
+ 
+ This option likewise has pros and cons:
+ <ul>
+ <li><b>PRO</b>: This option allows independently scaling the number of consumers and processors. This makes it
+ possible to have a single consumer that feeds many processor threads, avoiding any limitation on partitions.
+ <li><b>CON</b>: Guaranteeing order across the processors requires particular care as the threads will execute
+ independently an earlier chunk of data may actually be processed after a later chunk of data just due to the luck of
+ thread execution timing. For processing that has no ordering requirements this is not a problem.
+ <li><b>CON</b>: Manually committing the position becomes harder as it requires that all threads co-ordinate to ensure
+ that processing is complete for that partition.
+ </ul>
+ 
+ There are many possible variations on this approach. For example each processor thread can have it's own queue, and
+ the consumer threads can hash into these queues using the TopicPartition to ensure in-order consumption and simplify
+ commit.</div>
+</li>
+</ul>
+</div>
+<div class="summary">
+<ul class="blockList">
+<li class="blockList">
+<!-- ======== CONSTRUCTOR SUMMARY ======== -->
+<ul class="blockList">
+<li class="blockList"><a name="constructor_summary">
+<!--   -->
+</a>
+<h3>Constructor Summary</h3>
+<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Constructor Summary table, listing constructors, and an explanation">
+<caption><span>Constructors</span><span class="tabEnd">&nbsp;</span></caption>
+<tr>
+<th class="colOne" scope="col">Constructor and Description</th>
+</tr>
+<tr class="altColor">
+<td class="colOne"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#KafkaConsumer(java.util.Map)">KafkaConsumer</a></strong>(java.util.Map&lt;java.lang.String,java.lang.Object&gt;&nbsp;configs)</code>
+<div class="block">A consumer is instantiated by providing a set of key-value pairs as configuration.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colOne"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#KafkaConsumer(java.util.Map, org.apache.kafka.clients.consumer.ConsumerRebalanceCallback, org.apache.kafka.common.serialization.Deserializer, org.apache.kafka.common.serialization.Deserializer)">KafkaConsumer</a></strong>(java.util.Map&lt;java.lang.String,java.lang.Object&gt;&nbsp;configs,
+             <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer">ConsumerRebalanceCallback</a>&nbsp;callback,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>&gt;&nbsp;keyDeserializer,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;&nbsp;valueDeserializer)</code>
+<div class="block">A consumer is instantiated by providing a set of key-value pairs as configuration, a
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a> implementation, a key and a value <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>.</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colOne"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#KafkaConsumer(java.util.Properties)">KafkaConsumer</a></strong>(java.util.Properties&nbsp;properties)</code>
+<div class="block">A consumer is instantiated by providing a <code>Properties</code> object as configuration.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colOne"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#KafkaConsumer(java.util.Properties, org.apache.kafka.clients.consumer.ConsumerRebalanceCallback, org.apache.kafka.common.serialization.Deserializer, org.apache.kafka.common.serialization.Deserializer)">KafkaConsumer</a></strong>(java.util.Properties&nbsp;properties,
+             <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer">ConsumerRebalanceCallback</a>&nbsp;callback,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>&gt;&nbsp;keyDeserializer,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;&nbsp;valueDeserializer)</code>
+<div class="block">A consumer is instantiated by providing a <code>Properties</code> object as configuration and a
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a> implementation, a key and a value <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>.</div>
+</td>
+</tr>
+</table>
+</li>
+</ul>
+<!-- ========== METHOD SUMMARY =========== -->
+<ul class="blockList">
+<li class="blockList"><a name="method_summary">
+<!--   -->
+</a>
+<h3>Method Summary</h3>
+<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Method Summary table, listing methods, and an explanation">
+<caption><span>Methods</span><span class="tabEnd">&nbsp;</span></caption>
+<tr>
+<th class="colFirst" scope="col">Modifier and Type</th>
+<th class="colLast" scope="col">Method and Description</th>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#close()">close</a></strong>()</code>&nbsp;</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(org.apache.kafka.clients.consumer.CommitType)">commit</a></strong>(<a href="../../../../../org/apache/kafka/clients/consumer/CommitType.html" title="enum in org.apache.kafka.clients.consumer">CommitType</a>&nbsp;commitType)</code>
+<div class="block">Commits offsets returned on the last <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll()</code></a> for the subscribed list of topics and partitions.</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(java.util.Map, org.apache.kafka.clients.consumer.CommitType)">commit</a></strong>(java.util.Map&lt;<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>,java.lang.Long&gt;&nbsp;offsets,
+      <a href="../../../../../org/apache/kafka/clients/consumer/CommitType.html" title="enum in org.apache.kafka.clients.consumer">CommitType</a>&nbsp;commitType)</code>
+<div class="block">Commits the specified offsets for the specified list of topics and partitions to Kafka.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>long</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#committed(org.apache.kafka.common.TopicPartition)">committed</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition)</code>
+<div class="block">Fetches the last committed offset for the given partition (whether the commit happened by this process or
+ another).</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>java.util.Map&lt;<a href="../../../../../org/apache/kafka/common/MetricName.html" title="class in org.apache.kafka.common">MetricName</a>,? extends <a href="../../../../../org/apache/kafka/common/Metric.html" title="interface in org.apache.kafka.common">Metric</a>&gt;</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#metrics()">metrics</a></strong>()</code>
+<div class="block">Get the metrics kept by the consumer</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>java.util.List&lt;<a href="../../../../../org/apache/kafka/common/PartitionInfo.html" title="class in org.apache.kafka.common">PartitionInfo</a>&gt;</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#partitionsFor(java.lang.String)">partitionsFor</a></strong>(java.lang.String&nbsp;topic)</code>
+<div class="block">Get metadata about the partitions for a given topic.</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code><a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecords.html" title="class in org.apache.kafka.clients.consumer">ConsumerRecords</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)">poll</a></strong>(long&nbsp;timeout)</code>
+<div class="block">Fetches data for the topics or partitions specified using one of the subscribe APIs.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>long</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#position(org.apache.kafka.common.TopicPartition)">position</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition)</code>
+<div class="block">Returns the offset of the <i>next record</i> that will be fetched (if a record with that offset exists).</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)">seek</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition,
+    long&nbsp;offset)</code>
+<div class="block">Overrides the fetch offsets that the consumer will use on the next <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll(timeout)</code></a>.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToBeginning(org.apache.kafka.common.TopicPartition...)">seekToBeginning</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</code>
+<div class="block">Seek to the first offset for each of the given partitions</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToEnd(org.apache.kafka.common.TopicPartition...)">seekToEnd</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</code>
+<div class="block">Seek to the last offset for each of the given partitions</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(java.lang.String...)">subscribe</a></strong>(java.lang.String...&nbsp;topics)</code>
+<div class="block">Incrementally subscribes to the given list of topics and uses the consumer's group management functionality</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(org.apache.kafka.common.TopicPartition...)">subscribe</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</code>
+<div class="block">Incrementally subscribes to a specific topic partition and does not use the consumer's group management
+ functionality.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>java.util.Set&lt;<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&gt;</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscriptions()">subscriptions</a></strong>()</code>
+<div class="block">The set of partitions currently assigned to this consumer.</div>
+</td>
+</tr>
+<tr class="altColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#unsubscribe(java.lang.String...)">unsubscribe</a></strong>(java.lang.String...&nbsp;topics)</code>
+<div class="block">Unsubscribe from the specific topics.</div>
+</td>
+</tr>
+<tr class="rowColor">
+<td class="colFirst"><code>void</code></td>
+<td class="colLast"><code><strong><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#unsubscribe(org.apache.kafka.common.TopicPartition...)">unsubscribe</a></strong>(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</code>
+<div class="block">Unsubscribe from the specific topic partitions.</div>
+</td>
+</tr>
+</table>
+<ul class="blockList">
+<li class="blockList"><a name="methods_inherited_from_class_java.lang.Object">
+<!--   -->
+</a>
+<h3>Methods inherited from class&nbsp;java.lang.Object</h3>
+<code>clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait</code></li>
+</ul>
+</li>
+</ul>
+</li>
+</ul>
+</div>
+<div class="details">
+<ul class="blockList">
+<li class="blockList">
+<!-- ========= CONSTRUCTOR DETAIL ======== -->
+<ul class="blockList">
+<li class="blockList"><a name="constructor_detail">
+<!--   -->
+</a>
+<h3>Constructor Detail</h3>
+<a name="KafkaConsumer(java.util.Map)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>KafkaConsumer</h4>
+<pre>public&nbsp;KafkaConsumer(java.util.Map&lt;java.lang.String,java.lang.Object&gt;&nbsp;configs)</pre>
+<div class="block">A consumer is instantiated by providing a set of key-value pairs as configuration. Valid configuration strings
+ are documented <a href="http://kafka.apache.org/documentation.html#consumerconfigs" >here</a>. Values can be
+ either strings or objects of the appropriate type (for example a numeric configuration would accept either the
+ string "42" or the integer 42).
+ <p>
+ Valid configuration strings are documented at <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerConfig.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerConfig</code></a></div>
+<dl><dt><span class="strong">Parameters:</span></dt><dd><code>configs</code> - The consumer configs</dd></dl>
+</li>
+</ul>
+<a name="KafkaConsumer(java.util.Map, org.apache.kafka.clients.consumer.ConsumerRebalanceCallback, org.apache.kafka.common.serialization.Deserializer, org.apache.kafka.common.serialization.Deserializer)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>KafkaConsumer</h4>
+<pre>public&nbsp;KafkaConsumer(java.util.Map&lt;java.lang.String,java.lang.Object&gt;&nbsp;configs,
+             <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer">ConsumerRebalanceCallback</a>&nbsp;callback,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>&gt;&nbsp;keyDeserializer,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;&nbsp;valueDeserializer)</pre>
+<div class="block">A consumer is instantiated by providing a set of key-value pairs as configuration, a
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a> implementation, a key and a value <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>.
+ <p>
+ Valid configuration strings are documented at <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerConfig.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerConfig</code></a></div>
+<dl><dt><span class="strong">Parameters:</span></dt><dd><code>configs</code> - The consumer configs</dd><dd><code>callback</code> - A callback interface that the user can implement to manage customized offsets on the start and
+            end of every rebalance operation.</dd><dd><code>keyDeserializer</code> - The deserializer for key that implements <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>. The configure() method
+            won't be called in the consumer when the deserializer is passed in directly.</dd><dd><code>valueDeserializer</code> - The deserializer for value that implements <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>. The configure() method
+            won't be called in the consumer when the deserializer is passed in directly.</dd></dl>
+</li>
+</ul>
+<a name="KafkaConsumer(java.util.Properties)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>KafkaConsumer</h4>
+<pre>public&nbsp;KafkaConsumer(java.util.Properties&nbsp;properties)</pre>
+<div class="block">A consumer is instantiated by providing a <code>Properties</code> object as configuration. Valid
+ configuration strings are documented at <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerConfig.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerConfig</code></a> A consumer is instantiated by providing a
+ <code>Properties</code> object as configuration. Valid configuration strings are documented at
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerConfig.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerConfig</code></a></div>
+</li>
+</ul>
+<a name="KafkaConsumer(java.util.Properties, org.apache.kafka.clients.consumer.ConsumerRebalanceCallback, org.apache.kafka.common.serialization.Deserializer, org.apache.kafka.common.serialization.Deserializer)">
+<!--   -->
+</a>
+<ul class="blockListLast">
+<li class="blockList">
+<h4>KafkaConsumer</h4>
+<pre>public&nbsp;KafkaConsumer(java.util.Properties&nbsp;properties,
+             <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer">ConsumerRebalanceCallback</a>&nbsp;callback,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>&gt;&nbsp;keyDeserializer,
+             <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization">Deserializer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;&nbsp;valueDeserializer)</pre>
+<div class="block">A consumer is instantiated by providing a <code>Properties</code> object as configuration and a
+ <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRebalanceCallback.html" title="interface in org.apache.kafka.clients.consumer"><code>ConsumerRebalanceCallback</code></a> implementation, a key and a value <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>.
+ <p>
+ Valid configuration strings are documented at <a href="../../../../../org/apache/kafka/clients/consumer/ConsumerConfig.html" title="class in org.apache.kafka.clients.consumer"><code>ConsumerConfig</code></a></div>
+<dl><dt><span class="strong">Parameters:</span></dt><dd><code>properties</code> - The consumer configuration properties</dd><dd><code>callback</code> - A callback interface that the user can implement to manage customized offsets on the start and
+            end of every rebalance operation.</dd><dd><code>keyDeserializer</code> - The deserializer for key that implements <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>. The configure() method
+            won't be called in the consumer when the deserializer is passed in directly.</dd><dd><code>valueDeserializer</code> - The deserializer for value that implements <a href="../../../../../org/apache/kafka/common/serialization/Deserializer.html" title="interface in org.apache.kafka.common.serialization"><code>Deserializer</code></a>. The configure() method
+            won't be called in the consumer when the deserializer is passed in directly.</dd></dl>
+</li>
+</ul>
+</li>
+</ul>
+<!-- ============ METHOD DETAIL ========== -->
+<ul class="blockList">
+<li class="blockList"><a name="method_detail">
+<!--   -->
+</a>
+<h3>Method Detail</h3>
+<a name="subscriptions()">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>subscriptions</h4>
+<pre>public&nbsp;java.util.Set&lt;<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&gt;&nbsp;subscriptions()</pre>
+<div class="block">The set of partitions currently assigned to this consumer. If subscription happened by directly subscribing to
+ partitions using <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(org.apache.kafka.common.TopicPartition...)"><code>subscribe(TopicPartition...)</code></a> then this will simply return the list of partitions that
+ were subscribed to. If subscription was done by specifying only the topic using <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(java.lang.String...)"><code>subscribe(String...)</code></a>
+ then this will give the set of topics currently assigned to the consumer (which may be none if the assignment
+ hasn't happened yet, or the partitions are in the process of getting reassigned).</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#subscriptions()">subscriptions</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscriptions()"><code>subscriptions()</code></a></dd></dl>
+</li>
+</ul>
+<a name="subscribe(java.lang.String...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>subscribe</h4>
+<pre>public&nbsp;void&nbsp;subscribe(java.lang.String...&nbsp;topics)</pre>
+<div class="block">Incrementally subscribes to the given list of topics and uses the consumer's group management functionality
+ <p>
+ As part of group management, the consumer will keep track of the list of consumers that belong to a particular
+ group and will trigger a rebalance operation if one of the following events trigger -
+ <ul>
+ <li>Number of partitions change for any of the subscribed list of topics
+ <li>Topic is created or deleted
+ <li>An existing member of the consumer group dies
+ <li>A new member is added to an existing consumer group via the join API
+ </ul></div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#subscribe(java.lang.String...)">subscribe</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>topics</code> - A variable list of topics that the consumer wants to subscribe to</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(java.lang.String...)"><code>subscribe(String...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="subscribe(org.apache.kafka.common.TopicPartition...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>subscribe</h4>
+<pre>public&nbsp;void&nbsp;subscribe(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</pre>
+<div class="block">Incrementally subscribes to a specific topic partition and does not use the consumer's group management
+ functionality. As such, there will be no rebalance operation triggered when group membership or cluster and topic
+ metadata change.
+ <p></div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#subscribe(org.apache.kafka.common.TopicPartition...)">subscribe</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>partitions</code> - Partitions to incrementally subscribe to</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(org.apache.kafka.common.TopicPartition...)"><code>subscribe(TopicPartition...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="unsubscribe(java.lang.String...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>unsubscribe</h4>
+<pre>public&nbsp;void&nbsp;unsubscribe(java.lang.String...&nbsp;topics)</pre>
+<div class="block">Unsubscribe from the specific topics. This will trigger a rebalance operation and records for this topic will not
+ be returned from the next <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll()</code></a> onwards</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#unsubscribe(java.lang.String...)">unsubscribe</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>topics</code> - Topics to unsubscribe from</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#unsubscribe(java.lang.String...)"><code>unsubscribe(String...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="unsubscribe(org.apache.kafka.common.TopicPartition...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>unsubscribe</h4>
+<pre>public&nbsp;void&nbsp;unsubscribe(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</pre>
+<div class="block">Unsubscribe from the specific topic partitions. records for these partitions will not be returned from the next
+ <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll()</code></a> onwards</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#unsubscribe(org.apache.kafka.common.TopicPartition...)">unsubscribe</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>partitions</code> - Partitions to unsubscribe from</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#unsubscribe(org.apache.kafka.common.TopicPartition...)"><code>unsubscribe(TopicPartition...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="poll(long)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>poll</h4>
+<pre>public&nbsp;<a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecords.html" title="class in org.apache.kafka.clients.consumer">ConsumerRecords</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;&nbsp;poll(long&nbsp;timeout)</pre>
+<div class="block">Fetches data for the topics or partitions specified using one of the subscribe APIs. It is an error to not have
+ subscribed to any topics or partitions before polling for data.
+ <p>
+ The offset used for fetching the data is governed by whether or not <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)"><code>seek(TopicPartition, long)</code></a> is used.
+ If <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)"><code>seek(TopicPartition, long)</code></a> is used, it will use the specified offsets on startup and on every
+ rebalance, to consume data from that offset sequentially on every poll. If not, it will use the last checkpointed
+ offset using <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(java.util.Map, org.apache.kafka.clients.consumer.CommitType)"><code>commit(offsets, sync)</code></a> for the subscribed list of partitions.</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#poll(long)">poll</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>timeout</code> - The time, in milliseconds, spent waiting in poll if data is not available. If 0, waits
+            indefinitely. Must not be negative</dd>
+<dt><span class="strong">Returns:</span></dt><dd>map of topic to records since the last fetch for the subscribed list of topics and partitions</dd>
+<dt><span class="strong">Throws:</span></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/NoOffsetForPartitionException.html" title="class in org.apache.kafka.clients.consumer">NoOffsetForPartitionException</a></code> - If there is no stored offset for a subscribed partition and no automatic
+             offset reset policy has been configured.</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll(long)</code></a></dd></dl>
+</li>
+</ul>
+<a name="commit(java.util.Map, org.apache.kafka.clients.consumer.CommitType)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>commit</h4>
+<pre>public&nbsp;void&nbsp;commit(java.util.Map&lt;<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>,java.lang.Long&gt;&nbsp;offsets,
+          <a href="../../../../../org/apache/kafka/clients/consumer/CommitType.html" title="enum in org.apache.kafka.clients.consumer">CommitType</a>&nbsp;commitType)</pre>
+<div class="block">Commits the specified offsets for the specified list of topics and partitions to Kafka.
+ <p>
+ This commits offsets to Kafka. The offsets committed using this API will be used on the first fetch after every
+ rebalance and also on startup. As such, if you need to store offsets in anything other than Kafka, this API
+ should not be used.
+ <p>
+ A non-blocking commit will attempt to commit offsets asychronously. No error will be thrown if the commit fails.
+ A blocking commit will wait for a response acknowledging the commit. In the event of an error it will retry until
+ the commit succeeds.</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#commit(java.util.Map, org.apache.kafka.clients.consumer.CommitType)">commit</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>offsets</code> - The list of offsets per partition that should be committed to Kafka.</dd><dd><code>commitType</code> - Control whether the commit is blocking</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(java.util.Map, org.apache.kafka.clients.consumer.CommitType)"><code>commit(Map, CommitType)</code></a></dd></dl>
+</li>
+</ul>
+<a name="commit(org.apache.kafka.clients.consumer.CommitType)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>commit</h4>
+<pre>public&nbsp;void&nbsp;commit(<a href="../../../../../org/apache/kafka/clients/consumer/CommitType.html" title="enum in org.apache.kafka.clients.consumer">CommitType</a>&nbsp;commitType)</pre>
+<div class="block">Commits offsets returned on the last <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll()</code></a> for the subscribed list of topics and partitions.
+ <p>
+ This commits offsets only to Kafka. The offsets committed using this API will be used on the first fetch after
+ every rebalance and also on startup. As such, if you need to store offsets in anything other than Kafka, this API
+ should not be used.</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#commit(org.apache.kafka.clients.consumer.CommitType)">commit</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>commitType</code> - Whether or not the commit should block until it is acknowledged.</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#commit(org.apache.kafka.clients.consumer.CommitType)"><code>commit(CommitType)</code></a></dd></dl>
+</li>
+</ul>
+<a name="seek(org.apache.kafka.common.TopicPartition, long)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>seek</h4>
+<pre>public&nbsp;void&nbsp;seek(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition,
+        long&nbsp;offset)</pre>
+<div class="block">Overrides the fetch offsets that the consumer will use on the next <a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#poll(long)"><code>poll(timeout)</code></a>. If this API
+ is invoked for the same partition more than once, the latest offset will be used on the next poll(). Note that
+ you may lose data if this API is arbitrarily used in the middle of consumption, to reset the fetch offsets</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#seek(org.apache.kafka.common.TopicPartition, long)">seek</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seek(org.apache.kafka.common.TopicPartition, long)"><code>seek(TopicPartition, long)</code></a></dd></dl>
+</li>
+</ul>
+<a name="seekToBeginning(org.apache.kafka.common.TopicPartition...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>seekToBeginning</h4>
+<pre>public&nbsp;void&nbsp;seekToBeginning(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</pre>
+<div class="block">Seek to the first offset for each of the given partitions</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#seekToBeginning(org.apache.kafka.common.TopicPartition...)">seekToBeginning</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToBeginning(org.apache.kafka.common.TopicPartition...)"><code>seekToBeginning(TopicPartition...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="seekToEnd(org.apache.kafka.common.TopicPartition...)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>seekToEnd</h4>
+<pre>public&nbsp;void&nbsp;seekToEnd(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>...&nbsp;partitions)</pre>
+<div class="block">Seek to the last offset for each of the given partitions</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#seekToEnd(org.apache.kafka.common.TopicPartition...)">seekToEnd</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#seekToEnd(org.apache.kafka.common.TopicPartition...)"><code>seekToEnd(TopicPartition...)</code></a></dd></dl>
+</li>
+</ul>
+<a name="position(org.apache.kafka.common.TopicPartition)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>position</h4>
+<pre>public&nbsp;long&nbsp;position(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition)</pre>
+<div class="block">Returns the offset of the <i>next record</i> that will be fetched (if a record with that offset exists).</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#position(org.apache.kafka.common.TopicPartition)">position</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>partition</code> - The partition to get the position for</dd>
+<dt><span class="strong">Returns:</span></dt><dd>The offset</dd>
+<dt><span class="strong">Throws:</span></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/NoOffsetForPartitionException.html" title="class in org.apache.kafka.clients.consumer">NoOffsetForPartitionException</a></code> - If a position hasn't been set for a given partition, and no reset policy is
+             available.</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#position(org.apache.kafka.common.TopicPartition)"><code>position(TopicPartition)</code></a></dd></dl>
+</li>
+</ul>
+<a name="committed(org.apache.kafka.common.TopicPartition)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>committed</h4>
+<pre>public&nbsp;long&nbsp;committed(<a href="../../../../../org/apache/kafka/common/TopicPartition.html" title="class in org.apache.kafka.common">TopicPartition</a>&nbsp;partition)</pre>
+<div class="block">Fetches the last committed offset for the given partition (whether the commit happened by this process or
+ another). This offset will be used as the position for the consumer in the event of a failure.
+ <p>
+ This call may block to do a remote call if the partition in question isn't assigned to this consumer or if the
+ consumer hasn't yet initialized it's cache of committed offsets.</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#committed(org.apache.kafka.common.TopicPartition)">committed</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>partition</code> - The partition to check</dd>
+<dt><span class="strong">Returns:</span></dt><dd>The last committed offset or null if no offset has been committed</dd>
+<dt><span class="strong">Throws:</span></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/NoOffsetForPartitionException.html" title="class in org.apache.kafka.clients.consumer">NoOffsetForPartitionException</a></code> - If no offset has ever been committed by any process for the given
+             partition.</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#committed(org.apache.kafka.common.TopicPartition)"><code>committed(TopicPartition)</code></a></dd></dl>
+</li>
+</ul>
+<a name="metrics()">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>metrics</h4>
+<pre>public&nbsp;java.util.Map&lt;<a href="../../../../../org/apache/kafka/common/MetricName.html" title="class in org.apache.kafka.common">MetricName</a>,? extends <a href="../../../../../org/apache/kafka/common/Metric.html" title="interface in org.apache.kafka.common">Metric</a>&gt;&nbsp;metrics()</pre>
+<div class="block">Get the metrics kept by the consumer</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#metrics()">metrics</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#metrics()"><code>metrics()</code></a></dd></dl>
+</li>
+</ul>
+<a name="partitionsFor(java.lang.String)">
+<!--   -->
+</a>
+<ul class="blockList">
+<li class="blockList">
+<h4>partitionsFor</h4>
+<pre>public&nbsp;java.util.List&lt;<a href="../../../../../org/apache/kafka/common/PartitionInfo.html" title="class in org.apache.kafka.common">PartitionInfo</a>&gt;&nbsp;partitionsFor(java.lang.String&nbsp;topic)</pre>
+<div class="block">Get metadata about the partitions for a given topic. This method will issue a remote call to the server if it
+ does not already have any metadata about the given topic.</div>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#partitionsFor(java.lang.String)">partitionsFor</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">Parameters:</span></dt><dd><code>topic</code> - The topic to get partition metadata for</dd>
+<dt><span class="strong">Returns:</span></dt><dd>The list of partitions</dd><dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#partitionsFor(java.lang.String)"><code>partitionsFor(String)</code></a></dd></dl>
+</li>
+</ul>
+<a name="close()">
+<!--   -->
+</a>
+<ul class="blockListLast">
+<li class="blockList">
+<h4>close</h4>
+<pre>public&nbsp;void&nbsp;close()</pre>
+<dl>
+<dt><strong>Specified by:</strong></dt>
+<dd><code>close</code>&nbsp;in interface&nbsp;<code>java.io.Closeable</code></dd>
+<dt><strong>Specified by:</strong></dt>
+<dd><code>close</code>&nbsp;in interface&nbsp;<code>java.lang.AutoCloseable</code></dd>
+<dt><strong>Specified by:</strong></dt>
+<dd><code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html#close()">close</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../org/apache/kafka/clients/consumer/Consumer.html" title="interface in org.apache.kafka.clients.consumer">Consumer</a>&lt;<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">K</a>,<a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html" title="type parameter in KafkaConsumer">V</a>&gt;</code></dd>
+<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../org/apache/kafka/clients/consumer/KafkaConsumer.html#close()"><code>close()</code></a></dd></dl>
+</li>
+</ul>
+</li>
+</ul>
+</li>
+</ul>
+</div>
+</div>
+<!-- ========= END OF CLASS DATA ========= -->
+<!-- ======= START OF BOTTOM NAVBAR ====== -->
+<div class="bottomNav"><a name="navbar_bottom">
+<!--   -->
+</a><a href="#skip-navbar_bottom" title="Skip navigation links"></a><a name="navbar_bottom_firstrow">
+<!--   -->
+</a>
+<ul class="navList" title="Navigation">
+<li><a href="../../../../../overview-summary.html">Overview</a></li>
+<li><a href="package-summary.html">Package</a></li>
+<li class="navBarCell1Rev">Class</li>
+<li><a href="package-tree.html">Tree</a></li>
+<li><a href="../../../../../deprecated-list.html">Deprecated</a></li>
+<li><a href="../../../../../index-all.html">Index</a></li>
+<li><a href="../../../../../help-doc.html">Help</a></li>
+</ul>
+</div>
+<div class="subNav">
+<ul class="navList">
+<li><a href="../../../../../org/apache/kafka/clients/consumer/ConsumerRecords.html" title="class in org.apache.kafka.clients.consumer"><span class="strong">Prev Class</span></a></li>
+<li><a href="../../../../../org/apache/kafka/clients/consumer/MockConsumer.html" title="class in org.apache.kafka.clients.consumer"><span class="strong">Next Class</span></a></li>
+</ul>
+<ul class="navList">
+<li><a href="../../../../../index.html?org/apache/kafka/clients/consumer/KafkaConsumer.html" target="_top">Frames</a></li>
+<li><a href="KafkaConsumer.html" target="_top">No Frames</a></li>
+</ul>
+<ul class="navList" id="allclasses_navbar_bottom">
+<li><a href="../../../../../allclasses-noframe.html">All Classes</a></li>
+</ul>
+<div>
+<script type="text/javascript"><!--
+  allClassesLink = document.getElementById("allclasses_navbar_bottom");
+  if(window==top) {
+    allClassesLink.style.display = "block";
+  }
+  else {
+    allClassesLink.style.display = "none";
+  }
+  //-->
+</script>
+</div>
+<div>
+<ul class="subNavList">
+<li>Summary:&nbsp;</li>
+<li>Nested&nbsp;|&nbsp;</li>
+<li>Field&nbsp;|&nbsp;</li>
+<li><a href="#constructor_summary">Constr</a>&nbsp;|&nbsp;</li>
+<li><a href="#method_summary">Method</a></li>
+</ul>
+<ul class="subNavList">
+<li>Detail:&nbsp;</li>
+<li>Field&nbsp;|&nbsp;</li>
+<li><a href="#constructor_detail">Constr</a>&nbsp;|&nbsp;</li>
+<li><a href="#method_detail">Method</a></li>
+</ul>
+</div>
+<a name="skip-navbar_bottom">
+<!--   -->
+</a></div>
+<!-- ======== END OF BOTTOM NAVBAR ======= -->
+</body>
+</html>



Mime
View raw message