14

So I set up the power mock based on the reference guide here. It all seems to run perfectly fine with a single test class. But when executing multiple JUnit tests I am getting the following error on the second test class.

As you can see from the stacktrace below I am trying to mock a otto Bus instance. It seemed to mock properly on the first test class but on the the second class I am getting this class cast exception.

On the stacktrace I am getting suggestion to disable Objenisis cache but I am not sure how to accomplish that and if that is actually the root cause as I am using classloading-xstream:1.6.2 as per the Robolectric Wiki link attached above.

The thing is my setup works well if I run a single JUnit test class, but once I try to run all the tests in a package only the first test will work and subsequent tests will get the class cast exception. 

org.mockito.exceptions.base.MockitoException: 
    ClassCastException occurred while creating the mockito proxy :
      class to mock : 'com.squareup.otto.Bus', loaded by classloader : 'org.robolectric.internal.bytecode.InstrumentingClassLoader@1593948d'
      created class : 'com.squareup.otto.Bus$$EnhancerByMockitoWithCGLIB$$82a3b196', loaded by classloader : 'org.robolectric.internal.bytecode.InstrumentingClassLoader@1593948d'
      proxy instance class : 'com.squareup.otto.Bus$$EnhancerByMockitoWithCGLIB$$82a3b196', loaded by classloader : 'org.mockito.internal.creation.util.SearchingClassLoader@618ff5c2'
      instance creation by : ObjenesisInstantiator

    You might experience classloading issues, disabling the Objenesis cache *might* help (see MockitoConfiguration)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:61)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:49)
        at org.powermock.api.mockito.repackaged.CglibMockMaker.createMock(CglibMockMaker.java:24)
        at org.powermock.api.mockito.internal.mockmaker.PowerMockMaker.createMock(PowerMockMaker.java:45)
        at com.acme.android.myapp.services.gcm.handlers.RequestLogoutHandlerTest.setup(RequestLogoutHandlerTest.java:39)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        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.RunBefores.evaluate(RunBefores.java:24)
        at org.robolectric.RobolectricTestRunner$2.evaluate(RobolectricTestRunner.java:251)
        at org.robolectric.RobolectricTestRunner.runChild(RobolectricTestRunner.java:188)
        at org.robolectric.RobolectricTestRunner.runChild(RobolectricTestRunner.java:54)
        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.robolectric.RobolectricTestRunner$1.evaluate(RobolectricTestRunner.java:152)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
        at org.junit.runners.Suite.runChild(Suite.java:128)
        at org.junit.runners.Suite.runChild(Suite.java:27)
        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:78)
        at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
        at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
    Caused by: java.lang.ClassCastException: Cannot cast com.squareup.otto.Bus$$EnhancerByMockitoWithCGLIB$$82a3b196 to com.squareup.otto.Bus
        at java.lang.Class.cast(Class.java:3369)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:59)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:49)
        at org.powermock.api.mockito.repackaged.CglibMockMaker.createMock(CglibMockMaker.java:24)
        at org.powermock.api.mockito.internal.mockmaker.PowerMockMaker.createMock(PowerMockMaker.java:45)
        at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:33)
        at org.mockito.internal.MockitoCore.mock(MockitoCore.java:59)
        at org.mockito.Mockito.mock(Mockito.java:1285)
        at org.mockito.Mockito.mock(Mockito.java:1163)
        ... 36 more


    org.mockito.exceptions.base.MockitoException: 
    ClassCastException occurred while creating the mockito proxy :
      class to mock : 'com.squareup.otto.Bus', loaded by classloader : 'org.robolectric.internal.bytecode.InstrumentingClassLoader@1593948d'
      created class : 'com.squareup.otto.Bus$$EnhancerByMockitoWithCGLIB$$82a3b196', loaded by classloader : 'org.robolectric.internal.bytecode.InstrumentingClassLoader@1593948d'
      proxy instance class : 'com.squareup.otto.Bus$$EnhancerByMockitoWithCGLIB$$82a3b196', loaded by classloader : 'org.mockito.internal.creation.util.SearchingClassLoader@618ff5c2'
      instance creation by : ObjenesisInstantiator

    You might experience classloading issues, disabling the Objenesis cache *might* help (see MockitoConfiguration)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:61)
        at org.powermock.api.mockito.repackaged.ClassImposterizer.imposterise(ClassImposterizer.java:49)
        at org.powermock.api.mockito.repackaged.CglibMockMaker.createMock(CglibMockMaker.java:24)
        at org.powermock.api.mockito.internal.mockmaker.PowerMockMaker.createMock(PowerMockMaker.java:45)
        at com.acme.android.myapp.services.gcm.handlers.RequestLogoutHandlerTest.setup(RequestLogoutHandlerTest.java:39)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        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.RunBefores.evaluate(RunBefores.java:24)
        at org.robolectric.RobolectricTestRunner$2.evaluate(RobolectricTestRunner.java:251)
        at org.robolectric.RobolectricTestRunner.runChild(RobolectricTestRunner.java:188)
        at org.robolectric.RobolectricTestRunner.runChild(RobolectricTestRunner.java:54)
        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.robolectric.RobolectricTestRunner$1.evaluate(RobolectricTestRunner.java:152)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
        at org.junit.runners.Suite.runChild(Suite.java:128)
        at org.junit.runners.Suite.runChild(Suite.java:27)
        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:78)
        at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
        at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:6
4

2 回答 2

21

我建议按照异常消息中的建议禁用 Mockito 的 ClassCache。这是我通过在 Android Studio 中添加 MockitoConfiguration 类来禁用 Mockito ClassCache 的方法。

  1. 在你的单元测试目录 src/test/java 下，创建一个和 Mockito 配置包完全相同的包目录 org/mockito/configuration。

  2. 所以在完整的测试目录 src/test/java/org/mockito/configuration 下，添加一个名为 MockitoConfiguration 的新类。

  3. 覆盖 enableClassCache() 方法如下。

    package org.mockito.configuration;

    public class MockitoConfiguration extends DefaultMockitoConfiguration {

    @Override
    public boolean enableClassCache() {
        return false;
    }
}

  4. 当你在 src/java/test 下运行单元测试时，你的 MockitoConfiguration 应该被加载并且 Mockito 类缓存应该被禁用。

希望能帮助到你。

于 2016-01-29T03:25:30.453 回答
2

所以我通过添加解决了这个问题

@PowerMockIgnore({ "*.*" }) 
@PrepareForTest({ StaticClass1.class,StaticClass2.class })

这将使 Power mock 忽略所有类。对于我的情况，PowerMock 正在对总线进行类加载，在我的代码中实际上是由 Mockito 模拟的。一旦我在测试套件中的所有类上方添加了注释，就可以正常工作。

于 2015-10-09T04:15:21.467 回答