linux下安装java jdk后版本不对一例

我安装的是redhat 5.4 x86-64操作系统，正备搭建HADOOP集群的测试环境，安装HADOOP需要安装JAVA JDK，然后我从网上下载了jdk1.6的版本，但安装完后版本总是显示1.4.2。下面是安装的过程，安装完后环境变量我也设置了

[root@localhost init.d]# cd /soft
[root@localhost soft]# ls
jdk-6u35-linux-x64-rpm.bin
[root@localhost soft]# ls -l
total 67296
-rw-r----- 1 root root 68834864 Oct  9 17:40 jdk-6u35-linux-x64-rpm.bin
[root@localhost soft]# chmod +x jdk-6u35-linux-x64-rpm.bin
[root@localhost soft]# ./jdk-6u35-linux-x64-rpm.bin
Unpacking...
Checksumming...
Extracting...
UnZipSFX 5.50 of 17 February 2002, by Info-ZIP ( [email protected]).
  inflating: jdk-6u35-linux-amd64.rpm  
  inflating: sun-javadb-common-10.6.2-1.1.i386.rpm  
  inflating: sun-javadb-core-10.6.2-1.1.i386.rpm  
  inflating: sun-javadb-client-10.6.2-1.1.i386.rpm  
  inflating: sun-javadb-demo-10.6.2-1.1.i386.rpm  
  inflating: sun-javadb-docs-10.6.2-1.1.i386.rpm  
  inflating: sun-javadb-javadoc-10.6.2-1.1.i386.rpm  
Preparing...                ########################################### [100%]
   1:jdk                    ########################################### [100%]
Unpacking JAR files...
        rt.jar...
        jsse.jar...
        charsets.jar...
        tools.jar...
        localedata.jar...
        plugin.jar...
        javaws.jar...
        deploy.jar...
Installing JavaDB
Preparing...                ########################################### [100%]
   1:sun-javadb-common      ########################################### [ 17%]
   2:sun-javadb-core        ########################################### [ 33%]
   3:sun-javadb-client      ########################################### [ 50%]
   4:sun-javadb-demo        ########################################### [ 67%]
   5:sun-javadb-docs        ########################################### [ 83%]
   6:sun-javadb-javadoc     ########################################### [100%]
Java(TM) SE Development Kit 6 successfully installed.
Product Registration is FREE and includes many benefits:
* Notification of new versions, patches, and updates
* Special offers on Oracle products, services and training
* Access to early releases and documentation
Product and system data will be collected. If your configuration
supports a browser, the JDK Product Registration form will
be presented. If you do not register, none of this information
will be saved. You may also register your JDK later by
opening the register.html file (located in the JDK installation
directory) in a browser.
For more information on what data Registration collects and 
how it is managed and used, see:
http://java.sun.com/javase/registration/JDKRegistrationPrivacy.html
Press Enter to continue.....

Done.
[root@localhost soft]# java -version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2 20080704 (Red Hat 4.1.2-46)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[root@localhost soft]# cd /usr
[root@localhost usr]# cd java
[root@localhost java]# ls
default  jdk1.6.0_35  latest
[root@localhost java]# cd jdk1.6.0_35/
[root@localhost jdk1.6.0_35]# ls
bin  COPYRIGHT  include  jre  lib  LICENSE  man  README.html  register.html  register_ja.html  register_zh_CN.html  src.zip  THIRDPARTYLICENSEREADME.txt
[root@localhost jdk1.6.0_35]# vi /etc/profile


添加以下环境变量
export JAVA_HOME=/usr/java/jdk1.6.0_35
export JAVA_BIN=/usr/java/jdk1.6.0_35/bin
export PATH=$PATH:$JAVA_HOME/bin
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME JAVA_BIN PATH CLASSPATH

然后重新登录root，不记得使环境变量生效的命令了就直接登录的，登录后查看path环境变量
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
[root@localhost ~]# echo $PATH
/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/java/jdk1.6.0_35/bin:/root/bin
说明生效了

然后查看版本
[root@localhost soft]# java -version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2 20080704 (Red Hat 4.1.2-46)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

直接进入java目录执行还是一样
[root@localhost ~]# cd /usr
[root@localhost usr]# cd java
[root@localhost java]# ls
default  jdk1.6.0_35  latest
[root@localhost java]# cd jdk1.6.0_35/
[root@localhost jdk1.6.0_35]# ls
bin  COPYRIGHT  include  jre  lib  LICENSE  man  README.html  register.html  register_ja.html  register_zh_CN.html  src.zip  THIRDPARTYLICENSEREADME.txt
[root@localhost jdk1.6.0_35]# cd bin
[root@localhost bin]# pwd
/usr/java/jdk1.6.0_35/bin
[root@localhost bin]# java -version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2 20080704 (Red Hat 4.1.2-46)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 

经过上网搜索最后搞定了，还是环境变量的问题。把JAVA路径放到原来的path前面就好了，也是参考了别人的贴子才搞定的
http://bbs.chinaunix.net/thread-2019498-1-1.html

先用which java查看用的是哪个JAVA，结果显示为
[root@localhost soft]# which java
/usr/bin/java

说明并不是用的刚安装的JAVA版本，那么把JAVA路径放到PATH前面试试
export JAVA_HOME=/usr/java/jdk1.6.0_35
export JAVA_BIN=/usr/java/jdk1.6.0_35/bin
export PATH=$JAVA_HOME/bin:$PATH
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME JAVA_BIN PATH CLASSPATH

使环境变量生效后再看
[root@localhost ~]# which java
/usr/java/jdk1.6.0_35/bin/java
[root@localhost ~]# java -version
java version "1.6.0_35"
Java(TM) SE Runtime Environment (build 1.6.0_35-b10)
Java HotSpot(TM) 64-Bit Server VM (build 20.10-b01, mixed mode)