gradle - Android "has already been added to output" error for jar in a project dependency -

i have android project uses gradle project dependency. dependency project has library jar. when try compile project library compiled twice , error: error:class no.nordicsemi.android.log.logcontract.application has been added output. please remove duplicate copies.

here folder structure files in question:

>projectroot   >dfulibrary     >libs       -nrf-logger-v2.0.jar     -build.gradle   >logger     -build.gradle 

this build.gradle dfulibrary dependency:

apply plugin: 'com.android.library'  android {     compilesdkversion 19     buildtoolsversion "19.1.0"      defaultconfig {         applicationid "no.nordicsemi.android.dfu"         minsdkversion 18         targetsdkversion 19     }      buildtypes {         release {             minifyenabled false             proguardfiles getdefaultproguardfile('proguard-android.txt'), 'proguard-rules.txt'         }     } }  dependencies {     compile 'com.android.support:support-v4:+'     compile files('libs/nrf-logger-v2.0.jar') } 

this build.gradle logger (main project):

buildscript {     repositories {         mavencentral()     }     dependencies {         classpath 'com.android.tools.build:gradle:0.14.4'     } }  apply plugin: 'com.android.application'      android {      compilesdkversion 20     buildtoolsversion '20'      sourcesets {         main {             java.srcdirs "src/main/java"             res.srcdirs "src/main/res"             assets.srcdirs = ['assets']         }         androidtest.setroot('tests')         androidtest.java.srcdirs = ['tests/src']      }     dexoptions {         predexlibraries = false     } }  dependencies {     compile 'com.android.support:support-v4:+'     compile project':dfulibrary') } 

no.nordicsemi.android.log.logcontract.application class found of nrf-logger-v2.0.jar why being included twice , how can make sure not?

addition

here ../gradlew dependencies return:

_debugapk - ## internal use, not manually configure ## \--- project :dfulibrary  _debugcompile - ## internal use, not manually configure ## +--- project :dfulibrary \--- com.android.support:support-v4:+ -> 21.0.2      \--- com.android.support:support-annotations:21.0.2  _releaseapk - ## internal use, not manually configure ## \--- project :dfulibrary  _releasecompile - ## internal use, not manually configure ## +--- project :dfulibrary \--- com.android.support:support-v4:+ -> 21.0.2      \--- com.android.support:support-annotations:21.0.2  androidjacocoagent - jacoco agent use coverage data. \--- org.jacoco:org.jacoco.agent:0.7.1.201405082137 failed  androidjacocoant - jacoco ant tasks use execute gradle tasks. \--- org.jacoco:org.jacoco.ant:0.7.1.201405082137 failed   compile - classpath compiling main sources. \--- project :dfulibrary   provided - classpath compiling main sources. \--- com.android.support:support-v4:+ -> 21.0.2      \--- com.android.support:support-annotations:21.0.2 

i removed lines had no dependencies.

edit #2 output ./gradlew androiddependencies

:dfulibrary:androiddependencies debug \--- local: nrf-logger-v2.0.jar  debugtest +--- local: nrf-logger-v2.0.jar \--- debug      \--- local: nrf-logger-v2.0.jar  release \--- local: nrf-logger-v2.0.jar :nrftoolbox:androiddependencies debug +--- local: achartengine-1.1.0.jar \--- nrftoolbox:dfulibrary:unspecified      \--- local: nrf-logger-v2.0.jar  debugtest no dependencies  release +--- local: achartengine-1.1.0.jar \--- nrftoolbox:dfulibrary:unspecified      \--- local: nrf-logger-v2.0.jar  build successful 

bingo, found it.

just interesting , tried find your project @ internet. , started investigation .... :).

the problem hidden @ nrf-logger-v2.0.jar. contains .java , .class files. solution remove .java files it.

i did total commander. steps:

• rename nrf-logger-v2.0.jar nrf-logger-v2.0.zip;
• go inside , remove .java files;
• rename file jar;
• gradlew clean build or build-rebuild project @ android studio
• voila