ubuntu配置jdk

下载jdk：http://pan.baidu.com/s/1i3DqFMt

sudo mkdir /usr/lib/jvm/

sudo mv jdk-6u45-linux-x64.bin /usr/lib/jvm/
cd /usr/lib/jvm/
sudo chmod u+x /usr/lib/jvm/jdk-6u45-linux-x64.bin
sudo ./jdk-6u45-linux-x64.bin
sudo gedit /etc/environment




添加
PATH＝"/usr/lib/jvm/jdk1.6.0_45/bin" 
CLASSPATH=.:$java_home\lib\tools.jar:$java_home\lib\dt.jar 
JAVA_HOME="/usr/lib/jvm/jdk1.6.0_45" 


若PATH已存在，则用冒号作间隔，将jdk的bin目录地址加上






sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk1.6.0_45/bin/java 300 
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.6.0_45/bin/javac 300 
sudo update-alternatives --config java




java
javac
java -version