Ubuntu 下安装JDK

 

1.官网下载jdk-6u26-linux-i586.bin 

2.将安装文件放到 /opt/Java下面(任意设置)

3.sudo chmod u+x /opt/Java/jdk-6u26-linux-i586.bin  赋予jdk-6u26-linux-i586.bin权限

4.sudo /opt/Java/jdk-6u26-linux-i586.bin，以用户身份运行的话,安装完后会在/HOME/用户名  路径下出现一个文件夹jdk1.6.0_26。把他移动到/opt/Java下

5.配置环境参数，

sudo vi /etc/environment

在文件中修改PATH，增加CLASSPATH和JAVA_HOME，如下：

PATH＝"......:/opt/Java/jdk1.6.0_26/bin"

CLASSPATH=.:/opt/Java/jdk1.6.0_26/lib

JAVA_HOME=/opt/Java/jdk1.6.0_26

6.使环境变量生效 

sudo source /home/xxx/.bashrc，xxx是你的用户名

若ubuntu提示sudo: source: command not found，解决方法是去掉sudo，进入root模式直接执行source /home/xxx/.bashrc

7.由于ubuntu中可能会有默认的jdk，如openjdk，所以，为了使默认使用的是我们安装的jdk，进行如下操作：

update-alternatives --install /usr/bin/java java /opt/Java/jdk1.6.0_26/bin/java 300

update-alternatives --install /usr/bin/javac javac /opt/Java/jdk1.6.0_26/bin/javac 300 

8.通过这一步将我们安装的jdk加入java选单。

然后执行update-alternatives --config java。

9.最后检验java -version，看看是否成功。

These are my notes for 11.10 updated for Ubuntu 12.04.

Most installation notes refer to the no longer available sun-java6-jdk or an individual ppm, but these notes are for manually installing the downloaded files from Oracle. I'm referring to JDK6, but you could substitute JDK7 if that's what you need.

1. Download Java SE 6 JDK for Linux x86 self-extracting binary
   At the time of writing, the file I'm using is jdk-6u32-linux-i586.bin, but the filename will change as updates are released.
2. From the download folder, make the file executable
   chmod a+x jdk-6u32-linux-i586.bin
3. Apparently there isn't a jvm folder anymore, so create one.
   sudo mkdir /usr/lib/jvm
4. Move the file to the jvm folder
   sudo mv jdk-6u32-linux-i586.bin /usr/lib/jvm/
5. Change to the jvm folder and run the self-extracting binary
   cd /usr/lib/jvm
   sudo ./jdk-6u32-linux-i586.bin
   Everything will be extracted to a new jdk1.6.0_32 folder and you can delete the .bin file now.
6. Make symbolic links to the new java binary.
   sudo ln -s -b /usr/lib/jvm/jdk1.6.0_32/jre/bin/java /etc/alternatives/java
   sudo ln -s -b /usr/lib/jvm/jdk1.6.0_32/jre/bin/java /usr/bin/java
7. Double-check the version
   java -version

Now you can easily update and switch between JDK versions directly from the source.

Ubuntu GNU/Linux 12.04 LTS (Precise Pangolin) released. I wanted to manually install the Sun JDK 6 and 7 on Ubuntu.

Installing Sun JDK 6 on Ubuntu 12.04:

• Download the sun jdk 6 bin from here.

• Make the bin file executeable:

chmod +x jdk-6u32-linux-x64.bin

• Extract the bin file:

./jdk-6u32-linux-x64.bin

• Move extracted folder to this location:

sudo mv jdk1.6.0_32 /usr/lib/jvm/

• Install new java source in system:

sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.6.0_32/bin/javac 1
sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk1.6.0_32/bin/java 1
sudo update-alternatives --install /usr/bin/javaws javaws /usr/lib/jvm/jdk1.6.0_32/bin/javaws 1

• Choose default java:

sudo update-alternatives --config javac
sudo update-alternatives --config java
sudo update-alternatives --config javaws

• java version test:

java -version

• Verify the symlinks all point to the new java location:

ls -la /etc/alternatives/java*

• Enable Java plugin for Mozilla Firefox (even for Chrome)

#for 64-Bit jdk
sudo ln -s /usr/lib/jvm/jdk1.6.0_32/jre/lib/amd64/libnpjp2.so /usr/lib/mozilla/plugins
#for 32-Bit jdk
sudo ln -s /usr/lib/jvm/jdk1.6.0_32/jre/lib/i386/libnpjp2.so /usr/lib/mozilla/plugins

Installing Sun JDK 7 on Ubuntu 12.04:

• Download the sun jdk 7 tar file from here
• Extract the tar file:

tar -xvzf jdk-7u4-linux-x64.tar.gz

• Move extracted folder to this location:

sudo mv jdk1.7.0_04 /usr/lib/jvm/

• Install new java source in system:

sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.7.0_04/bin/javac 1
sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk1.7.0_04/bin/java 1
sudo update-alternatives --install /usr/bin/javaws javaws /usr/lib/jvm/jdk1.7.0_04/bin/javaws 1

• Choose default java:

sudo update-alternatives --config javac
sudo update-alternatives --config java
sudo update-alternatives --config javaws

• java version test:

java -version

• Verify the symlinks all point to the new java location:

ls -la /etc/alternatives/java*

• Enable Java plugin for Mozilla Firefox (even for Chrome)

#for 64-Bit jdk
sudo ln -s /usr/lib/jvm/jdk1.7.0_04/jre/lib/amd64/libnpjp2.so /usr/lib/mozilla/plugins
#for 32-Bit jdk
sudo ln -s /usr/lib/jvm/jdk1.7.0_04/jre/lib/i386/libnpjp2.so /usr/lib/mozilla/plugins

Update: I have added Java Web Start configuration (Thanks Jack).

Update: I have added Java Plugin configuration for Mozilla Firefox even for Chrome (Thanks shetty).

Update: JAVA_HOME configuration: Some tools require JAVA_HOME variable. You can set JAVA_HOME in Ubuntu so simple: Edit the file .bashrc under your home directory and add the following lines: (if .bashrc is hidden click in Nautilus Menu View > Show Hidden Files)

export JAVA_HOME=/path/your/jdk
export PATH=$JAVA_HOME/bin:$PATH