Android Studio构建失败，出现异常任务'：app：dexDebug'的执行失败

控制台日志：

失败的

失败：生成失败，发生异常。

• 出了什么问题：任务'：app：dexDebug'的执行失败。

  com.android.ide.common.process.ProcessException：org.gradle.process.internal.ExecException：处理'命令'C：\ Program Files（x86）\ Java \ jdk1.8.0 \ bin \ java.exe''完成非零退出值2

• 尝试：使用--info或--debug选项运行，以获取更多日志输出。

• 异常是：org.gradle.api.tasks.TaskExecutionException：任务'：app：dexDebug'的执行失败。在org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions（ExecuteActionsTaskExecuter.java:69）在org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute（ExecuteActionsTaskExecuter.java:46）在org.gradle org.gradle的.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute（PostExecutionAnalysisTaskExecuter.java:35）位于org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute（SkipUpToDateTaskExecuter.java:64）位于org.gradle。 org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute（SkipEmptySourceFilesTaskExecuter.java:42）上的.tasks.execution.ValidatingTaskExecuter.execute（ValidatingTaskExecuter.java:58）在org.gradle.api.internal.tasks.exe上。

build.gradle文件：

    apply plugin: 'com.android.application'

android {
    compileSdkVersion 21
    buildToolsVersion "22.0.0"

    defaultConfig {
        applicationId "com.appdomain.appname"
        minSdkVersion 15
        targetSdkVersion 21
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }
    }

    dependencies {
        compile 'com.android.support:support-v4:19.1.+'
        compile 'com.google.guava:guava:10.0.1'
        compile 'com.google.android.gms:play-services:+'
        compile 'com.android.support:appcompat-v7:21.0.3'
        compile files('libs/gdata-client-1.0.jar')
        compile files('libs/gdata-client-meta-1.0.jar')
        compile files('libs/gdata-contacts-3.0.jar')
        compile files('libs/gdata-contacts-meta-3.0.jar')
        compile files('libs/gdata-core-1.0.jar')
        compile files('libs/libGoogleAnalyticsServices.jar')
        compile files('libs/mpandroidchartlibrary-1-7-4.jar')
        compile files('libs/recyclerview.jar')
    }