title: Android Studio throws an exception trying to execute an app with logback support and minSdkVersion = 17
body: <p>I'm writing an Android app with Android Studio 2.2.<br>
  I defined the <code>minSdkVersion 17</code> and I added the following libraries to use <a href="https://github.com/tony19/logback-android" rel="nofollow">logback-android</a>:</p>
  
  <pre><code>compile 'com.github.tony19:logback-android-core:1.1.1-6'
  compile 'com.github.tony19:logback-android-classic:1.1.1-6'
  compile 'ch.qos.logback:logback-classic:1.1.7'
  </code></pre>
  
  <p>After that, the building process works but when I try to execute on a device (virtual or real device) the process aborts with the following exception.</p>
  
  <pre><code>Error:Execution failed for task ':app:transformClassesWithDexForDebug'.
  &gt; com.android.build.api.transform.TransformException:com.android.ide.common.process.ProcessException:java.util.concurrent.ExecutionException: com.android.dex.DexException: Multiple dex files define Lch/qos/logback/classic/AsyncAppender;
  </code></pre>
  
  <p>If I define the <code>minSdkVersion 19</code> there is not any problem, the application is built and executed smoothly on the device, but, I need minSdkVersion.</p>
  
  <p>You can reproduce the issue easily just creating a simple application, adding the mentioned libraries and defining the <code>minSdkVersion 17</code>.</p>
  
  <p>Do you know how it could be solved?</p>
  
  <p>Thanks in advance.</p>
  
  <hr>
  
  <p><strong>UPDATED</strong><br>
  Attaching the <strong>build.gradle</strong> file:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 23
      buildToolsVersion "23.0.3"
      defaultConfig {
          applicationId "com.dcsoft.multidexfailurewithlogback"
          minSdkVersion 17
          targetSdkVersion 23
          versionCode 1
          versionName "1.0"
          testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
          exclude group: 'com.android.support', module: 'support-annotations'
      })
      compile 'com.android.support:appcompat-v7:23.3.0'
      testCompile 'junit:junit:4.12'
      compile 'com.github.tony19:logback-android-core:1.1.1-6'
      compile 'com.github.tony19:logback-android-classic:1.1.1-6'
      compile 'ch.qos.logback:logback-classic:1.1.7'
  }
  </code></pre>
  
  <p><strong>UPDATE 2</strong><br>
  Adding my <strong>MainActivity.java</strong>:</p>
  
  <pre><code>package com.dcsoft.multidexfailurewithlogback;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import android.os.Bundle;
  import android.support.v7.app.AppCompatActivity;
  
  public class MainActivity extends AppCompatActivity {
  
    private static final Logger LOGGER = LoggerFactory.getLogger(MainActivity.class);
  
    @Override
    protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
    }
  }
  </code></pre>