I got this error and I don't know why, if someone know how to fix it it will be awesome.
here is the complete error:
Error:Execution failed for task ':app:preDexDebug'.
> com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'C:\Program Files\Java\jdk1.8.0_65\bin\java.exe'' finished with non-zero exit value 1