linux java 版本

之前linux已经安装了1.6的版本， 我想要升级，于是安装了1.7，

   /etc/profile 的最后几行是这么写的：

JAVA_HOME=/usr/java/jdk1.7.0_79
JRE_HOME=/usr/java/jdk1.7.0_79/jre
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
CLASSPATH=.:$JAVA_HOME/lib/jt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
export JAVA_HOME JRE_HOME PATH CLASSPATH

 然后 source /etc/profile

[root@/usr/java/jdk1.7.0_79/jre/lib/management]#java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.1) (rhel-1.45.1.11.1.el6-x86_64)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

————————  为什么 java -version 总是显示还是 1.6 呢， 气死我了

虽然

[root@/usr/java/jdk1.7.0_79/jre/lib/management]#echo $JAVA_HOME
/usr/java/jdk1.7.0_79

但是

[root@/usr/java/jdk1.7.0_79/jre/lib/management]#which java
/usr/bin/java

而

[root@/usr/java/jdk1.7.0_79/jre/lib/management]#!ps
ps -ef| grep tomcat
root 4356 1 0 Oct20 ? 00:00:00 /usr/libexec//gvfs-fuse-daemon /usr/linkapp/bin/tomcat-nas/.gvfs
root 5087 1 1 03:55 ? 00:08:28 /usr/java/jdk1.7.0_79/jre/bin/java -Djava.util.logging.config.file=/usr/linkapp/bin/tomcat-master/conf/logging.properties -Xdebug -Xrunjdwp:transport=dt_socket,address=8786,server=y,suspend=n -server -Xms2048M -Xmx8092M -Xss256k -XX:NewRatio=4 -XX:SurvivorRatio=4 -XX:MaxPermSize=2048M -XX:MaxTenuringThreshold=0 -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/usr/linkapp/bin/tomcat-master/endorsed -classpath /usr/linkapp/bin/tomcat-master/bin/bootstrap.jar -Dcatalina.base=/usr/linkapp/bin/tomcat-master -Dcatalina.home=/usr/linkapp/bin/tomcat-master -Djava.io.tmpdir=/usr/linkapp/bin/tomcat-master/temp org.apache.catalina.startup.Bootstrap start

————  ps 显示java命令路径为 /usr/java/jdk1.7.0_79/jre/bin/java

执行

[root@/usr/java/jdk1.7.0_79/jre/lib/management]#export $PATH
-bash: export: `/usr/lib64/qt-3.3/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/java/jdk1.7.0_79/bin:/usr/java/jdk1.7.0_79/jre/bin:/root/bin': not a valid identifier

忽然想起了，命令的顺序问题—— /usr/bin:  在 /usr/java/jdk1.7.0_79/bin前面 ，于是

把

PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin

改成

PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$PATH

　　

[root@/usr/linkapp/bin/tomcat-nas]#source /etc/profile
Add some aliases !!!

[root@/usr/linkapp/bin/tomcat-nas]#
[root@/usr/linkapp/bin/tomcat-nas]#export $PATH
-bash: export: `/usr/lib64/qt-3.3/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/java/jdk1.7.0_79/bin:/usr/java/jdk1.7.0_79/jre/bin:/root/bin': not a valid identifier

[root@/usr/linkapp/bin/tomcat-nas]#which java
/usr/java/jdk1.7.0_79/bin/java
[root@/usr/linkapp/bin/tomcat-nas]#
[root@/usr/linkapp/bin/tomcat-nas]#
[root@/usr/linkapp/bin/tomcat-nas]#java -version
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)

一切正常