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# Mac下安装多版本java

因为公司有些项目比较老，跑在jdk7，无奈之前只好安装一下。

低版本链接：

<http://www.oracle.com/technetwork/java/javase/downloads/jdk7u9-downloads-1859576.html>

安装dmg格式的java。目前本机安装了两个版本，jdk7和jdk8。

```
cd ~
vim .bash_profile
# 添加下面的

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

#默认JDK7
export JAVA_HOME=$JAVA_7_HOME

#alias命令动态切换JDK版本
alias jdk7="export JAVA_HOME=$JAVA_7_HOME"
alias jdk8="export JAVA_HOME=$JAVA_8_HOME"
```

然后运行java -version可以看到已经切换到jdk7了。


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