不可能用mockito模拟一个类:接收NoClassDefFoundError

Question

我的Android项目中有大约100个单元测试。一切都很完美。我使用 JUnit + Mockito + PowerMock（在处理困难的静态类时）。

在编写我最新的测试时，我对这个我不理解的非常奇怪的错误感到惊讶。

当我在 setUp（） 函数中执行此操作时：

playerAccessor = mock(PlayerAccessor.class);

所有测试都因这个非常奇怪的错误而崩溃：

java.lang.NoClassDefFoundError: android/media/MediaPlayer$OnCompletionListener
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$100(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at org.powermock.core.classloader.MockClassLoader.loadModifiedClass(MockClassLoader.java:178)
    at org.powermock.core.classloader.DeferSupportingClassLoader.loadClass(DeferSupportingClassLoader.java:68)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.Class.getDeclaredMethods0(Native Method)
    at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
    at java.lang.Class.getDeclaredMethods(Unknown Source)
    at org.mockito.cglib.core.ReflectUtils.addAllMethods(ReflectUtils.java:349)
    at org.mockito.cglib.proxy.Enhancer.getMethods(Enhancer.java:422)
    at org.mockito.cglib.proxy.Enhancer.generateClass(Enhancer.java:457)
    at org.mockito.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
    at org.mockito.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:217)
    at org.mockito.cglib.proxy.Enhancer.createHelper(Enhancer.java:378)
    at org.mockito.cglib.proxy.Enhancer.createClass(Enhancer.java:318)
    at org.mockito.internal.creation.jmock.ClassImposterizer.createProxyClass(ClassImposterizer.java:124)
    at org.mockito.internal.creation.jmock.ClassImposterizer.imposterise(ClassImposterizer.java:60)
    at org.mockito.internal.creation.jmock.ClassImposterizer.imposterise(ClassImposterizer.java:52)
    at org.mockito.internal.creation.CglibMockMaker.createMock(CglibMockMaker.java:24)
    at org.powermock.api.mockito.internal.mockmaker.PowerMockMaker.createMock(PowerMockMaker.java:43)
    at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:32)
    at org.mockito.internal.MockitoCore.mock(MockitoCore.java:59)
    at org.mockito.Mockito.mock(Mockito.java:1258)
    at org.mockito.Mockito.mock(Mockito.java:1135)
    at com.stingray360.clap.ondemand.OnDemandMessageHandlerTest.setUp(OnDemandMessageHandlerTest.java:60)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.junit.internal.runners.MethodRoadie.runBefores(MethodRoadie.java:133)
    at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:96)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
    at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:87)
    at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:50)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
    at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
    at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:122)
    at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:106)
    at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
    at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.ClassNotFoundException: android.media.MediaPlayer$OnCompletionListener
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 62 more

我唯一的线索是PlayerAccessor有一个名为 register 的函数，它接受一个实现OnCompletionListener接口的对象播放器。但我不是在嘲笑Player，而是在嘲笑PlayerAccessor.

我是否需要在我的模拟函数中指定一些东西，这样它就不会尝试模拟玩家访问器使用的每个对象？我的测试（导入???）中是否缺少某些内容。

编辑

一个答案建议我将所需的库（com.google.android）放在"测试"范围内，但由于它是Android库，因此需要"提供"范围。如果我更改它，我的单元测试确实开始工作，但是当我运行该应用程序时，我在控制台中收到大错误，告诉我包含 android jar 是一件非常糟糕的事情......那么其他解决方案是什么???

Answer 1

如果你模拟的类导入了另一个类，你必须在类路径上拥有该类，否则类加载器将失败，无论你是否实际使用了它提供的任何功能。

如果您使用 maven 进行构建，则可以轻松添加具有测试范围的依赖项 jar

Answer 2

Eclipse 应该尊重 pom 配置