http://blog.csdn.net/seapeak007/article/details/53257817
方式1.Eclipse Marketplace
方式2.下载压缩包
Instal New Software 选择压缩文件，打钩，一直next
压缩包下载：
https://github.com/cnfree/Eclipse-Class-Decompiler
https://github.com/cnfree/Eclipse-Class-Decompiler/releases/download/v2.10.0/eclipse-class-decompiler-update_v2.10.0.zip