cmd命令行输入java命令报如下错误：
Failed reading value of registry key:
Software\JavaSoft\Java Runtime Environment\1.7\JavaHome
Error: could not find java.dll
Error: Could not find Java SE Runtime Environment.
解决方法：
打开cmd命令行，输入regedit打开注册表，删除HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft，问题即可解决