Intellij IDEA:libXtst.so.6: cannot open shared object file: No such file or directory

I am doing a *** java project of my school.
We should implement a shipbattle game, I never play it, but it seems very boring.
The JFrame method is provided, all we should code is just.....implement the rest part:

When I run this program, an error stopped it.
Exception in thread "main" java.lang.UnsatisfiedLinkError: /home/tearsyu/idea-IC-145.597.3/jdk1.8.0_77/jre/lib/i386/libawt_xawt.so: libXtst.so.6: cannot open shared object file: No such file or directory
It's strange becase I did download and install libXtst.
By the way, I learn a new great command because of this error----locate(read more)

java/Day2$ locate libXtst/usr/lib/x86_64-linux-gnu/libXtst.so.6/usr/lib/x86_64-linux-gnu/libXtst.so.6.1.0

But, my libXtst works for 64bit while Jre search a version 32bit so I need  to download 32bit version of libXtst.

sudo apt-get install libxtst6:i386

THEN IT WORKS.

 (tucao: hao luan chou de jie mian)