Nowadays, many projects contain Java source code that is UTF-8 encoded, which allows you to add special characters like €, Chinese, Korean, Japanese characters, etc into your Java source code. But this brings a problem when compiling the code in Windows platform.
java unmappable character for encoding GBK (or CP1252)
If you are using Gradle, the quick fix is to add the following lines into build.gradle file
compileJava.options.encoding = 'UTF-8' compileTestJava.options.encoding = 'UTF-8'
Alternatively, you can set up a system/environment variable
If you set this variable to -Dfile.encoding=UTF8, everytime a JVM is started, it will use the proper encoding.