Karaf - Kafka OSGI 捆绑包 - 生产者问题

Question

我正在尝试在 apache Karaf 版本 4.0.3 中为 Kafka 生产者创建一个简单的捆绑包。

这是我的 Java 代码

Properties props = new Properties();
props.put("bootstrap.servers", "localhost:9092");
props.put("acks", "all");
props.put("retries", 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
props.put("buffer.memory", 33554432);
//props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
//props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
props.put("partitioner.class","org.apache.kafka.clients.producer.internals.DefaultPartitioner");
Producer<String, String> producer = new KafkaProducer<String,String>(props,new StringSerializer(),new StringSerializer());
//for(int i = 0; i < 100; i++)
    producer.send(new ProducerRecord<String, String>("test","data", outputData));

producer.close();

我已经在 pom.xml 中明确声明了各自的依赖

<dependency>
        <groupId>org.apache.servicemix.bundles</groupId>
        <artifactId>org.apache.servicemix.bundles.kafka-clients</artifactId>
        <version>0.9.0.0_1</version>
</dependency>

我也部署了那个 kafka 客户端包。

但在启动制作人时，我在 first Attempt 看到以下异常。

Exception in thread "pool-135-thread-1" java.lang.ExceptionInInitializerError
    at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:194)
    .
    .
    .
    at com.google.common.util.concurrent.Futures$6.run(Futures.java:1319)
    at com.gilt.gfc.guava.future.FutureConverters$ScalaFutureAdapter$$anonfun$addListener$1.apply(FutureConverters.scala:72)
    at com.gilt.gfc.guava.future.FutureConverters$ScalaFutureAdapter$$anonfun$addListener$1.apply(FutureConverters.scala:72)
    at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.kafka.common.config.ConfigException: Invalid value org.apache.kafka.clients.producer.internals.DefaultPartitioner for configuration partitioner.class: Class org.apache.kafka.clients.producer.internals.DefaultPartitioner could not be found.
    at org.apache.kafka.common.config.ConfigDef.parseType(ConfigDef.java:255)
    at org.apache.kafka.common.config.ConfigDef.define(ConfigDef.java:78)
    at org.apache.kafka.common.config.ConfigDef.define(ConfigDef.java:94)
    at org.apache.kafka.clients.producer.ProducerConfig.<clinit>(ProducerConfig.java:206)
    ... 12 more

然后连续这个...

Exception in thread "pool-136-thread-1" java.lang.NoClassDefFoundError: Could not initialize class org.apache.kafka.clients.producer.ProducerConfig
at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:194)
.
.
.
at com.google.common.util.concurrent.Futures$6.run(Futures.java:1319)
at com.gilt.gfc.guava.future.FutureConverters$ScalaFutureAdapter$$anonfun$addListener$1.apply(FutureConverters.scala:72)
at com.gilt.gfc.guava.future.FutureConverters$ScalaFutureAdapter$$anonfun$addListener$1.apply(FutureConverters.scala:72)
at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745

有人遇到过类似的问题吗？

Answer 1

使用 Kafka 客户端版本 0.8.2.2_1，解决了这个问题。

Answer 2

我在 0.9.0 中看到了同样的问题。事实证明，设置了一个 Thread 上下文加载器，在这种情况下，Kafka 使用该类加载器来解析。所以线程上下文类加载器应该是：

• 一个可以解析所有 Kafka 相关内容的类加载器
• null

不知道这是否会咬我，但补充：

Thread.currentThread().setContextClassLoader(null);

成功了。

Answer 3

可能我对其他人有用，在JIRA 中建议解决方法

props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, org.apache.kafka.common.serialization.StringSerializer.class);

props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, org.apache.kafka.common.serialization.StringSerializer.class);