1.mac下檢視安裝的jdk版本

bogon:~ yxk$ /usr/libexec/java_home -V Matching Java Virtual Machines (2):     1.8.0_144, x86_64:  "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home     1.7.0_80, x86_64:   "Java SE 7" /Library/Java/JavaVirtualMachines/jdk1.7.0_80.jdk/Contents/Home

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home

2.設定JAVA_HOME變數

bogon:~ yxk$ vim .bash_profile export JAVA_HOME=$(/usr/libexec/java_home)

3.測試jdk的安裝

bogon:~ yxk$ java -version java version "1.8.0_144" Java(TM) SE Runtime Environment (build 1.8.0_144-b01) Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)  

4.切換jdk版本

通過設定當前使用者的profile檔案修改當前使用者的環境變數

bogon:~ yxk$ vim .bash_profile

# 設定 JDK 7 export JAVA_7_HOME=`/usr/libexec/java_home -v 1.7` # 設定 JDK 8 export JAVA_8_HOME=`/usr/libexec/java_home -v 1.8`

#預設JDK 7 export JAVA_HOME=$JAVA_7_HOME

#alias命令動態切換JDK版本 alias jdk7="export JAVA_HOME=$JAVA_7_HOME" alias jdk8="export JAVA_HOME=$JAVA_8_HOME" bogon:~ yxk$ source .bash_profile bogon:~ yxk$ java -version java version "1.7.0_80" Java(TM) SE Runtime Environment (build 1.7.0_80-b15) Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode) #通過執行jdk8可以將jdk版本切換到jdk1.8 bogon:~ yxk$ jdk8 bogon:~ yxk$ java -version java version "1.8.0_144" Java(TM) SE Runtime Environment (build 1.8.0_144-b01) Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)