在 Ubuntu 中轻松更改 $JAVA_HOME
在 Ubuntu 中,我想在 Java 5 和 6 之间来回切换我的 JAVA_HOME 环境变量.
In Ubuntu, I'd like to switch my JAVA_HOME environment variable back and forth between Java 5 and 6.
我打开一个终端并输入以下内容来设置 JAVA_HOME 环境变量:
I open a terminal and type in the following to set the JAVA_HOME environment variable:
export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun
在同一个终端窗口中,我键入以下内容以检查环境变量是否已更新:
And in that same terminal window, I type the following to check that the environment variable has been updated:
echo $JAVA_HOME
我看到 /usr/lib/jvm/java-1.5.0-sun 这正是我期待看到的.另外我修改~/.profile,将JAVA_HOME环境变量设置为/usr/lib/jvm/java-1.5.0-sun.
And I see /usr/lib/jvm/java-1.5.0-sun which is what I'm expecting to see. In addition, I modify ~/.profile and set the JAVA_HOME environment variable to /usr/lib/jvm/java-1.5.0-sun.
现在问题来了——当我打开一个新的终端窗口并通过输入 echo $JAVA_HOME 检查我的 JAVA_HOME 环境变量时,我看到我的 JAVA_HOME 环境变量已恢复为 Java6. 当我重新启动我的机器(或注销并重新登录,我想)时,JAVA_HOME 环境变量被设置为 Java 5(大概是因为我在 ~/.profile 中所做的修改).
And now for the problem--when I open a new terminal window and I check my JAVA_HOME environment variable by typing in echo $JAVA_HOME I see that my JAVA_HOME environment variable has been reverted back to Java 6. When I reboot my machine (or log out and back in, I suppose) the JAVA_HOME environment variable is set to Java 5 (presumably because of the modification I made in my ~/.profile).
有没有办法解决这个问题,这样我就可以更改我的 JAVA_HOME 环境而无需注销并重新登录(并在所有新的终端窗口中更改环境变量stick)?
Is there a way around this so that I can change my JAVA_HOME environment without having to log out and back in (AND make that environment variable change stick in all new terminal windows)?
将环境变量放入全局/etc/environment
文件:
Put the environment variables into the global /etc/environment
file:
...
export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun
...
在您希望更新变量的每个 shell 中执行source/etc/environment":
Execute "source /etc/environment" in every shell where you want the variables to be updated:
$ source /etc/environment
检查它是否有效:
$ echo $JAVA_HOME
$ /usr/lib/jvm/java-1.5.0-sun
太好了,无需注销.
如果您只想在终端中设置 JAVA_HOME 环境变量,请在 ~/.bashrc 文件中设置.
If you want to set JAVA_HOME environment variable in only the terminal, set it in ~/.bashrc file.