反編譯時出錯apk

我想反編譯一個apk。但我面對這個錯誤：反編譯時出錯apk

Could not find the main class: brut.apktool.Main. Program will exit. 
Exception in thread "main" ----------------------------------------------------- 
--------------------- 
|Wed 02/26/2014 -- 0:25:58.98| 
-------------------------------------------------------------------------- 
java version "1.6.0_39" 
Java(TM) SE Runtime Environment (build 1.6.0_39-b04) 
Java HotSpot(TM) Client VM (build 20.14-b01, mixed mode, sharing) 
java.lang.UnsupportedClassVersionError: brut/apktool/Main : Unsupported major.mi 
nor version 51.0 
     at java.lang.ClassLoader.defineClass1(Native Method) 
     at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) 
     at java.lang.ClassLoader.defineClass(ClassLoader.java:615) 
     at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:14 
1) 
     at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) 
     at java.net.URLClassLoader.access$000(URLClassLoader.java:58) 
     at java.net.URLClassLoader$1.run(URLClassLoader.java:197) 
     at java.security.AccessController.doPrivileged(Native Method) 
     at java.net.URLClassLoader.findClass(URLClassLoader.java:190) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306) 
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:247) 
Could not find the main class: brut.apktool.Main. Program will exit. 
Exception in thread "main" Press any key to continue . . .

是否有任何身體知道什麼是brut.apktool.Main，我該如何解決？

編輯

我安裝了JDK 1.7和改變了我的JAV_HOME和路徑值，現在我得到這個錯誤：

-------------------------------------------------------------------------- 
java version "1.7.0_51" 
Java(TM) SE Runtime Environment (build 1.7.0_51-b13) 
Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode) 
Press any key to continue . . .

來源

2014-02-25 Husein Behboodi Rad