运行elasticsearch报错

一.问题描述：

安装完elasticsearch后,运行报错

root@localhost work]# Exception in thread "main" java.lang.UnsupportedClassVersionError: org/elasticsearch/bootstrap/Elasticsearch : Unsupported major.minor version 51.0

        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:643)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:277)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:73)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:212)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:323)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:268)

Could not find the main class: org.elasticsearch.bootstrap.Elasticsearch. Program will exit.

二.解决问题：

1.在 /etc/profile相应位置添加java环境变量(如果没有安装java运行环境则安装)

HOSTNAME=`/bin/hostname 2>/dev/null`
HISTSIZE=1000
if [ "$HISTCONTROL" = "ignorespace" ] ; then
    export HISTCONTROL=ignoreboth
else
    export HISTCONTROL=ignoredups
fi


JAVA_HOME=/usr/java/jdk1.7.0_72
export PATH=$JAVA_HOME/bin:$PATH
export CLASSPATH=.:$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar:$CLASSPATH
PATH=$JAVA_HOME/bin:$PATH

2.在/etc/init.d/elasticsearch添加

lockfile=/var/lock/subsys/$prog


source /etc/profile
# backwards compatibility for old config sysconfig files, pre 0.90.1
if [ -n $USER ] && [ -z $ES_USER ] ; then 
   ES_USER=$USER
fi