mac-osx 10.9.4 Hadoop 2.7.1 Exception in thread "main" java.lang.UnsupportedClassVersionError: Unsupported major.minor version 51.0

Question

尝试运行 namenode 格式时，出现以下错误。谁能建议如何解决它？ ( 在 mac os x 10.9.4 版本。Hadoop 2.7.1 版本)

Pro:hadoop-2.7.1 hadoop$ bin/hdfs namenode -format
Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apache/hadoop/hdfs/server/namenode/NameNode : Unsupported major.minor version 51.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
    at java.net.URLClassLoader.access[=10=]0(URLClassLoader.java:58)
    at java.net.URLClassLoader.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)

Java版本如下...

Pro:hadoop-2.7.1 hadoop$ java -version
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-462-11M4609)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-462, mixed mode)

在 hadoop-env.sh 中给出的路径为

export JAVA_HOME=/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home

Answer 1

51 Java class 文件格式的主要版本符合 Java 7.

您的版本中的 Hadoop 库需要 Java 7，但您尝试运行它在 Java 6 运行时间将不起作用。

mac-osx 10.9.4 Hadoop 2.7.1 Exception in thread "main" java.lang.UnsupportedClassVersionError: Unsupported major.minor version 51.0

mac-osx 10.9.4 Hadoop 2.7.1 Exception in thread "main" java.lang.UnsupportedClassVersionError: Unsupported major.minor version 51.0

java

macos

hadoop

hadoop2