Install JDK in ubuntu12

I have installed ubuntu12.10 in the past two days, and then installed various Java Development Programs on it. I have referenced many websites and learned a lot. The content to be recorded below is too small for the Linux old bird, but it is indeed helpful for new beginners (such as me. I would like to make the following series of records (or summarize it yourself, or refer to the online document ):

UBUntu12Install JDK 7: Install JDK (http://blog.csdn.net/binbinxyz/article/details/8498336) in ubuntu12)

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1> download the package (at6/7 (tar.gz); 2> extract it to the user's main directory; 3> move it to the/OPT directory; 4> RUN startup. SH; 5> enter http: // localhost: 8080 in the browser address bar to test

Ubuntu12Install myeclipSE10: Installing myeclipse10 (http://blog.csdn.net/binbinxyz/article/details/8498343) in ubuntu12)

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Install JDK 7 in ubuntu12. Here is a summary:

Step 1: Download jdk-7-linux-i586.tar.gz
You can download it directly on the Oracle Official Website:

Http://www.oracle.com/technetwork/java/javase/downloads/java-se-jdk-7-download-432154.html

PS: Pay attention to the selection of the system version. You can find the answer by using the 32-bit or 64-bit uname-a command.
Step 2: unzip and install
Access the tar.gz file...
Tar-xzf jdk-7-linux-i586.tar.gz

Next, move the extracted folder to the/usr/lib/JVM directory.
Before that, you must have root permissions Su-L and then enter the password of the root account, you also need to create a folder mkdir/usr/lib/JVM in the/usr/lib directory.
After completing these preparations, we can move the JDK file to the desired location.
MV jdk1.7.0/usr/lib/JVM
In order to facilitate the configuration of environment variables, we change the JDK file name, the general online JDK file changed to jdk-7-sun.
MV/usr/lib/JVM/jdk1.7.0/usr/lib/JVM/Java-7-sun
Step 3: Modify Environment Variables
Vim ~ /. Bashrc
(If Vim is not installed, run: sudo apt-Get install Vim first)
Export java_home =/usr/lib/JVM/Java-7-sun
Export jre_home =$ {java_home}/JRE
Export classpath =. :$ {java_home}/lib :$ {jre_home}/lib
Export path =$ {java_home}/bin: $ path
Add to end
Save and exit
Source ~ /. Bashrc
Step 4: configure the default JDK version
Sudo Update-alternatives -- install/usr/bin/Java/usr/lib/JVM/Java-7-sun/bin/Java 300
Sudo Update-alternatives -- install/usr/bin/javac/usr/lib/JVM/Java-7-sun/bin/javac 300
Sudo Update-alternatives -- install/usr/bin/Jar/usr/lib/JVM/Java-7-sun/bin/jar 300
Check
Sudo Update-alternatives -- config Java
Step 5: view the Java version
Command line:
Java-version
The system will list
Java version "1.7.0 _ 01"
Java (TM) se Runtime Environment (build 1.7.0 _ 01-b08)
Java hotspot (TM) Client VM (build 21.1-b02, mixed mode)

From:
Http://blog.csdn.net/luxiaoyu_sdc/article/details/7303155sudo Update-alternatives -- install/usr/bin/Java/usr/lib/JVM/Java-7-sun/bin/Java 300