任务“:app:preDexDebug”执行失败。> com.android.ide.common.process.ProcessException:

I am trying to integrate apache POI library with my android application. For that i have added apache poi jar files in to my libs folder and using "compile files" I'am compiling through build.gradle. But when I do gradle sync there is no problem in it. After doing gradle sync, when I try to run the application I am gettinf the error Execution Failed for task ':app:preDexDebug'.I am trying to integrate apache POI library wit