When jdk compiled java files: character encoding GBK unmappable

This problem occurs several solutions:

　　1, use javac to compile java files in cmd

　　　　Such as: javac test.java

　　　The solution: add encoding options when compiling

　　　　　　 javac -encoding UTF-8 test.java   or    javac -encoding UTF-8 -d . test.java

　　2 This error occurs when importing compile java file separate IntelliJ IDEA

　　　  Solution: As the IDEA does not have the automatic conversion character encoding types, so you need to click on the bottom right corner of the UTF-8 Save as type save GBK, GBK again click click save as UTF-8 can be.

　　3, use Notepad ++ to open the java file, click Encoding -> into ANSI encoding, save it.