root@localhost opt]# rpm -qa|grep java java-1.6.0-openjdk-1.6.0.37-1.13.9.4.el5_11tzdata-java-2015g-1.el5//卸載[root@localhost opt]# rpm -e --allmatches --nodeps java-1.6.0-openjdk-1.6.0.37-1.13.9.4.el5_11[root@localhost opt]# rpm -e --allmatches --nodeps tzdata-java-2015g-1.el5

[root@localhost jre-1.6.0-openjdk.x86_64]# yum -y list java*Loaded plugins: fastestmirrorLoading mirror speeds from cached hostfile * addons: mirrors.btte.net * base: centos.ustc.edu.cn * extras: centos.ustc.edu.cn * updates: centos.ustc.edu.cnInstalled Packagesjava-1.6.0-openjdk.x86_64          1:1.6.0.37-1.13.9.4.el5_11        installedAvailable Packagesjava-1.4.2-gcj-compat.x86_64          1.4.2.0-40jpp.115          base  java-1.4.2-gcj-compat-devel.i386         1.4.2.0-40jpp.115          base  java-1.4.2-gcj-compat-devel.x86_64        1.4.2.0-40jpp.115          base  java-1.4.2-gcj-compat-javadoc.x86_64        1.4.2.0-40jpp.115          base  java-1.4.2-gcj-compat-src.x86_64         1.4.2.0-40jpp.115          base  java-1.6.0-openjdk-demo.x86_64         1:1.6.0.37-1.13.9.4.el5_11        updates java-1.6.0-openjdk-devel.x86_64         1:1.6.0.37-1.13.9.4.el5_11        updates java-1.6.0-openjdk-javadoc.x86_64        1:1.6.0.37-1.13.9.4.el5_11        updates java-1.6.0-openjdk-src.x86_64         1:1.6.0.37-1.13.9.4.el5_11        updates java-1.7.0-openjdk.x86_64          1:1.7.0.91-2.6.2.1.el5_11        updates java-1.7.0-openjdk-demo.x86_64         1:1.7.0.91-2.6.2.1.el5_11        updates java-1.7.0-openjdk-devel.x86_64         1:1.7.0.91-2.6.2.1.el5_11        updates java-1.7.0-openjdk-javadoc.x86_64        1:1.7.0.91-2.6.2.1.el5_11        updates java-1.7.0-openjdk-src.x86_64         1:1.7.0.91-2.6.2.1.el5_11        updates java_cup.x86_64             1:0.10-0.k.6jpp.1          base  java_cup-javadoc.x86_64           1:0.10-0.k.6jpp.1          base  java_cup-manual.x86_64           1:0.10-0.k.6jpp.1          base  javacc.x86_64             4.0-3jpp.3            base  javacc-demo.x86_64            4.0-3jpp.3            base  javacc-manual.x86_64            4.0-3jpp.3            base

[root@localhost jre-1.6.0-openjdk.x86_64]# yum search jdkLoaded plugins: fastestmirrorLoading mirror speeds from cached hostfile * addons: mirrors.btte.net * base: centos.ustc.edu.cn * extras: centos.ustc.edu.cn * updates: centos.ustc.edu.cn========================================================== Matched: jdk ==========================================================java-1.6.0-openjdk.x86_64 : OpenJDK Runtime Environmentjava-1.6.0-openjdk-demo.x86_64 : OpenJDK Demosjava-1.6.0-openjdk-devel.x86_64 : OpenJDK Development Environmentjava-1.6.0-openjdk-javadoc.x86_64 : OpenJDK API Documentationjava-1.6.0-openjdk-src.x86_64 : OpenJDK Source Bundlejava-1.7.0-openjdk.x86_64 : OpenJDK Runtime Environmentjava-1.7.0-openjdk-demo.x86_64 : OpenJDK Demosjava-1.7.0-openjdk-devel.x86_64 : OpenJDK Development Environmentjava-1.7.0-openjdk-javadoc.x86_64 : OpenJDK API Documentationjava-1.7.0-openjdk-src.x86_64 : OpenJDK Source Bundlegnu-crypto-sasl-jdk1.4.x86_64 : Gnu Crypto SASL APIjakarta-commons-beanutils.x86_64 : Jakarta Commons BeanUtils Packagejakarta-commons-collections.x86_64 : Jakarta Commons Collections Packagejakarta-commons-launcher.x86_64 : The Launcher Component is designed to be a cross platform Java application launcher.ldapjdk.x86_64 : The Mozilla LDAP Java SDKldapjdk-javadoc.x86_64 : Javadoc for ldapjdkmockobjects-alt-jdk1.4.x86_64 : Mockable API for JDK 1.4mockobjects-jdk1.4.x86_64 : MockObjects for 1.4 JDK

[root@localhost ~]# yum install java-1.6.0-openjdk.x86_64 …… Total download size: 44 MIs this ok [y/N]: y

[root@localhost ~]# java -versionjava version "1.6.0_37"OpenJDK Runtime Environment (IcedTea6 1.13.9) (rhel-1.13.9.4.el5_11-x86_64)OpenJDK 64-Bit Server VM (build 23.25-b01, mixed mode)

[root@localhost ~]# cd /usr/lib/jvm[root@localhost jvm]# lltotal 24drwxr-xr-x 3 root root 4096 Jan 12 20:01 java-1.6.0-openjdk-1.6.0.37.x86_64lrwxrwxrwx 1 root root 21 Jan 12 20:01 jre -> /etc/alternatives/jrelrwxrwxrwx 1 root root 27 Jan 12 20:01 jre-1.6.0 -> /etc/alternatives/jre_1.6.0lrwxrwxrwx 1 root root 38 Jan 12 20:01 jre-1.6.0-openjdk.x86_64 -> java-1.6.0-openjdk-1.6.0.37.x86_64/jrelrwxrwxrwx 1 root root 29 Jan 12 20:01 jre-openjdk -> /etc/alternatives/jre_openjdk

[root@localhost jvm]# cd /etc/alternatives[root@localhost alternatives]# lltotal 204lrwxrwxrwx 1 root root 46 Jan 12 20:01 java -> /usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/java

[root@localhost bin]# vi /etc/profile

#set java environmentJAVA_HOME=/usr/lib/jvm/jre-1.6.0-openjdk.x86_64PATH=$PATH:$JAVA_HOME/binCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jarexport JAVA_HOME CLASSPATH PATH

[root@localhost alternatives]# . /etc/profile

[root@localhost jvm]# cd /etc/alternatives[root@localhost alternatives]# ln -s /usr/lib/jvm/jre-1.6.0-openjdk.x86_64/ java_home

#set java environmentJAVA_HOME=/etc/alternatives/java_homePATH=$PATH:$JAVA_HOME/binCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jarexport JAVA_HOME CLASSPATH PATH

[root@localhost alternatives]# export |grep JAVA_HOMEdeclare -x JAVA_HOME="/etc/alternatives/java_home"