Exception when consuming message from kafka - apache-kafka

Question

In a Java project that is built by maven I'm trying to create a basic kafka (producer consumer) example.
when running this code I get this exception:
Exception in thread "main" java.lang.UnsupportedClassVersionError: kafka/javaapi/producer/async/CallbackHandler : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at kafka.javaapi.consumer.SimpleConsumer.fetch(SimpleConsumer.scala:43)
at com.taptica.avrotest.KafkaLocalBroker.main(KafkaLocalBroker.java:101)
I also tried running similar code against a real kafka server (with zoo-keeper) and again - message was sent successfully to kafka (I could also verify it in my kafka server) but when tried to consume it got the same mentioned exception.
Since I'm suspecting this is a matter of jar-versions mismatch here is my pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mycompany.rtb</groupId>
<artifactId>rtb-accumulation</artifactId>
<version>0.0.1-SNAPSHOT</version>
<properties>
<avro.version>1.7.5</avro.version>
<org.springframework-version>3.2.3.RELEASE</org.springframework-version>
<jackson-version>1.9.13</jackson-version>
<kafka-version>0.7.2-SNAPSHOT</kafka-version>
<cglib-version>2.2.2</cglib-version>
<org.slf4j-version>1.7.5</org.slf4j-version>
</properties>
<repositories>
<repository>
<id>clojars.org</id>
<url>http://clojars.org/repo</url>
</repository>
</repositories>
<dependencies>
<!-- Spring -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${org.springframework-version}</version>
<exclusions>
<!-- Exclude Commons Logging in favor of SLF4j -->
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${org.springframework-version}</version>
</dependency>
<!-- Kafka -->
<dependency>
<groupId>org.clojars.jasonjckn</groupId>
<artifactId>kafka_2.9.2</artifactId>
<version>${kafka-version}</version>
</dependency>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.9.2</version>
</dependency>
<!-- Avro -->
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro</artifactId>
<version>${avro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro-maven-plugin</artifactId>
<version>${avro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro-compiler</artifactId>
<version>${avro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro-ipc</artifactId>
<version>${avro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro-mapred</artifactId>
<version>${avro.version}</version>
</dependency>
<!-- Jackson -->
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>${jackson-version}</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-core-asl</artifactId>
<version>${jackson-version}</version>
</dependency>
<!-- Test -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<!-- Logging -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${org.slf4j-version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>${org.slf4j-version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${org.slf4j-version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.16</version>
<exclusions>
<exclusion>
<groupId>javax.mail</groupId>
<artifactId>mail</artifactId>
</exclusion>
<exclusion>
<groupId>javax.jms</groupId>
<artifactId>jms</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jdmk</groupId>
<artifactId>jmxtools</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jmx</groupId>
<artifactId>jmxri</artifactId>
</exclusion>
</exclusions>
<scope>compile</scope>
</dependency>
<!-- Misc -->
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>r09</version>
</dependency>
<dependency>
<groupId>cglib</groupId>
<artifactId>cglib</artifactId>
<version>2.2.2</version>
</dependency>
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>jsr250-api</artifactId>
<version>1.0</version>
</dependency>
</dependencies>
</project>
Any ideas?

Answer 1

You need to upgrade your java compiler.
Have a look at this link : How to fix java.lang.UnsupportedClassVersionError: Unsupported major.minor version