getting this error : Execution failed for task ':app:transformClassesWithDexForDebug'

Question

I am using Jaunt to parse website in my application. project filelist

But It always gives me this error

Error:Execution failed for task ':app:transformClassesWithDexForDebug'.

com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'C:\Program Files\Java\jdk1.8.0_40\bin\java.exe'' finished with non-zero exit value 1

This is my gradle file :

apply plugin: 'com.android.application'

android {
    compileSdkVersion 22
    buildToolsVersion "22.0.1"

    defaultConfig {
        applicationId "com.suvariyaraj.webscrapping"
        minSdkVersion 14
        targetSdkVersion 22
        versionCode 1
        versionName "1.0"
    } 
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile files('libs/jaunt1.1.2.jar')
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:22.1.1'
}

This is Hello world application (By default application). I have not added anything except Jaunt lib.

I have tried adding multiDexEnabled true, javaMaxHeapSize "4g" but it did not work. So please suggest me what should I do?