java - guava AbstractIterator - duplicate class -

i want migrate 1 of our projects ant+ivy gradle. when compile sources using gradle error:

...\guava-gwt-14.0.1.jar(com/google/common/collect/abstractiterator.java):64: error: duplicate class: com.google.common.collect.abstractiterator public abstract class abstractiterator<t> extends unmodifiableiterator<t> {                 ^ ...\guava-gwt-14.0.1.jar(com/google/common/base/optional.java):223: error: cannot access abstractiterator         return new abstractiterator<t>() {                    ^   bad source file: ...\guava-gwt-14.0.1.jar(com/google/common/base/abstractiterator.java)     file not contain class com.google.common.base.abstractiterator     please remove or make sure appears in correct subdirectory of sourcepath. note: input files use or override deprecated api. note: recompile -xlint:deprecation details. note: input files use unchecked or unsafe operations. note: recompile -xlint:unchecked details. 2 errors 

i checked abstractiterator.java in com.google.common.collect , com.google.common.base (as wrote in error). how solve problem?

[update]

this gradle build (very simple - it's beginning of migration ant gradle)

apply plugin: 'java'  compilejava.options.encoding = 'iso-8859-1'  repositories {     mavencentral()     maven {         url 'http://gwtquery-plugins.googlecode.com/svn/mavenrepo'     }     ivy {         url 'http://ivyrep/shared'         url 'http://ivyrep/public'         layout "pattern", { artifact "[organisation]/[module]/[revision]/[type]s/[artifact].[ext]" }     } }  // know conigurations should repaired (testcompile, runtime) beggining of migration ant gradle dependencies {     compile 'net.sourceforge.cobertura:cobertura:1.9.4.1'     compile 'com.google.gwt:gwt-servlet:2.5.0'     compile 'com.google.gwt:gwt-user:2.5.0'     compile 'com.google.gwt:gwt-dev:2.5.0'     compile 'com.google.gwt.inject:gin:2.0.0'     compile 'com.googlecode.gwtquery:gwtquery:1.3.2'     compile 'com.googlecode.gwtquery.bundles:gquery-dnd-bundle:1.0.6'     compile 'org.hamcrest:hamcrest-library:1.3'     compile 'org.mockito:mockito-all:1.9.5'     compile 'junit:junit:4.10'     compile 'org.easytesting:fest-assert-core:2.0m10'     compile 'xmlunit:xmlunit:1.3'     compile 'org.reflections:reflections:0.9.9-rc1' } 

i should add gwt project.

[update]

problem solved. i've excluded guava-gwt compile scope , started work. not best solution works.

apply plugin: 'java'  configurations { guavagwt }  dependencies {     guavagwt 'com.google.guava:guava-gwt:14.0.1'     // other dependencies }  task compilegwt (dependson: classes) << {     // [...]         javaexec {             main = 'com.google.gwt.dev.compiler'             maxheapsize = '512m'             classpath {                 [                     sourcesets.main.java.srcdirs,                     sourcesets.main.output.resourcesdir,                     sourcesets.main.output.classesdir,                     sourcesets.main.compileclasspath,                     configurations.guavagwt, // use guava-gwt                 ]             }             args =                     [                         modulename,                         '-war',                         builddir,                         '-loglevel',                         'info',                         // '-draftcompile' // speeds compile 25%                     ]         }     // [...] }  compilejava {     configurations.compile.exclude module:'guava-gwt' // exclude guava-gwt     // job } 

i got same issue today, , fixed adding gradle build file:

tasks.withtype(javacompile) {     options.compilerargs += ["-sourcepath", ""] } 

thanks peter's answer in post: http://forums.gradle.org/gradle/topics/compilation_fails_when_i_use_guavas_optional_class_duplicate_class_com_google_common_collect_abstractiterator