title: Java finished with non-zero exit value 2 - Android Gradle
body: <p>I'm getting this error executing my Android app (I cleaned it and then built it, but the error is still present)</p>
  
  <ul>
  <li>Sync: OK </li>
  <li>Make Project: OK</li>
  <li>Clean: OK</li>
  <li>Run: Error</li>
  </ul>
  
  <blockquote>
    <p>Error:Execution failed for task ':app:dexDebug' .com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'C:\Program Files\Java\jdk1.7.0_25\bin\java.exe'' finished with non-zero exit value 2</p>
  </blockquote>
  
  <p>My gradle file:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
  compileSdkVersion 21
  buildToolsVersion "21.1.2"
  defaultConfig {
      applicationId "com.rzr.rzevallosr.miappdepruebas"
      minSdkVersion 19
      targetSdkVersion 21
      versionCode 1
      versionName "1.0"
  }
  buildTypes {
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
      }
  }
  
  productFlavors {
  }
  
  repositories {
      mavenCentral()
      flatDir {
          dirs 'libs'
      }
  }
  }
  
  dependencies {
  compile fileTree(dir: 'libs', include: ['*.jar'])
  
  // This library handles authentication and authorization
  compile 'com.spotify.sdk:spotify-auth:1.0.0-beta9@aar'
  // This library handles music playback
  compile 'com.spotify.sdk:spotify-player:1.0.0-beta9@aar'
  
  compile 'com.android.support:appcompat-v7:21.0.3'
  compile 'com.android.support:recyclerview-v7:21.0.+'
  
  compile 'com.squareup.retrofit:retrofit:1.9.0'
  compile 'com.squareup.okhttp:okhttp-urlconnection:2.2.0'
  compile 'com.squareup.okhttp:okhttp:2.2.0'
  
  compile files('libs/spotify-web-api-android-master-0.1.0.jar')
  compile files('libs/okio-1.3.0.jar')
  }
  </code></pre>
  
  <p>EDIT: I didn't see "compile fileTree(dir: 'libs', include: ['*.jar'])" it was compiling twice my libraries, so i just comment:</p>
  
  <pre><code>//compile 'com.squareup.retrofit:retrofit:1.9.0'
  //compile 'com.squareup.okhttp:okhttp-urlconnection:2.2.0'
  //compile 'com.squareup.okhttp:okhttp:2.2.0'
  
  //compile files('libs/spotify-web-api-android-master-0.1.0.jar')
  //compile files('libs/okio-1.3.0.jar')
  </code></pre>
  
  <p>and it works fine.</p>