Android w/ Kotlin pure-java-Junit NoClassDefFoundError 解决方法不

Question

可靠地重现错误的存储库：explodes/bug-kotlin-junit

我的安卓应用程序由一个应用程序模块和 4 个库模块组成。

我的测试是用纯Java编写的。不接触 Kotlin 代码的测试运行良好，但是当我运行使用 ( MyKotlinObj::methodRef ( 或初始化类 ( new MyKotlinObj() 的测试时，我的测试将失败并显示以下内容：

java.lang.NoClassDefFoundError: com/explod/api/UserCreated
    at com.explod.api.Bug.initUserCreated_shouldNotTriggerNoClassDefFoundError(Bug.java:19)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:131)
Caused by: java.lang.ClassNotFoundException: com.explod.api.UserCreated
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 28 more

用：

• 安卓工作室 3.0 金丝雀 2

• 构建工具 26.0.0-rc2

• Kotlin 版本 1.1.2-4

• 安卓-格拉德尔插件 3.0.0-alpha2

• Gradle gradle-4.0-milestone-1

• 目标开发工具包 25

• 最小 SDK 19

此处建议的解决方法对我不起作用：

android {
    task copyTestClasses(type: Copy) {
        from "build/tmp/kotlin-classes/debugUnitTest"
        into "build/intermediates/classes/debug"
    }

看起来Android Studio团队可能有一个解决方案，但我希望有一个可行的解决方法。我的问题有什么不同吗？在我的测试中没有 Kotlin 代码。

Answer 1

事实证明，解决方法的目标副本目录不正确。

我一直在使用：

task copyTestClasses(type: Copy) {
    from "build/tmp/kotlin-classes/devDebugUnitTest"
    into "build/intermediates/classes/devDebug"
}
task copySdkClasses(type: Copy) {
    from "build/tmp/kotlin-classes/devDebug"
    into "build/intermediates/classes/dev/debug"
}

但以下内容对我有用：

task copyTestClasses(type: Copy) {
    from "build/tmp/kotlin-classes/devDebugUnitTest"
    into "build/intermediates/classes/dev/debug"
}
task copySdkClasses(type: Copy) {
    from "build/tmp/kotlin-classes/devDebug"
    into "build/intermediates/classes/dev/debug"
}

在全新版本中，SDK 类不可用。我还需要向运行配置添加:api:assembleDevDebug，使其从干净的构建中工作。