It inside his Java is added manually, but added to the/etc/profile error may lead to environment variables, a command fails, the way such as boot reboot, you use ubunt again, actually can use apt - get to add a current version of the default Java (if only to open a Java program to use, such as fastqc, etc.), ubunt default Java will do the trick
You can type the command Java first see if you have any Java ubunt
If not he will prompt you to use sudo apt - get the install x x x x x x x different versions of Java, you can according to their own requirements to install Java, the default is actually rather easy to use, should be here at/usr/bin, after adding this file is already in the $PATH, so don't have to configure the environment variables, convenient
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