使用Powermock模拟类的构造函数时出现ExceptionInInitializerError.怎么解决？

Question

这是我的情况.我有一个AbstractController类.它有一个子类控制器.在AbstractController的一个方法中,实例化了一个新的ApplicationLock.我想在为Controller编写ut时模拟ApplicationLock.我写了一个如下的测试用例.

@test
public void testMethod(){
    ApplicationLock mockLock=PowerMockito.mock(ApplicationLock.class);
    PowerMockito.when(mockLock.tryObtain()).thenReturn(true);
    PowerMockito.whenNew(ApplicationLock.class).withArguments(argThat(new IsFile()),anyString()).thenReturn(mockLock);
}

我已经为测试类添加了必要的注释.

@RunWith(PowerMockRunner.class)

@PrepareForTest({AbstractController.class})

但是在运行此测试用例时出现以下错误.这是AbstractController中的静态初始化程序.

引起:com.acompany.controller.common.AbstractController中的java.lang.NullPointerException.(AbstractController.java:65)

private static final String DEFAULT_FOLDER = AbstractController.class.getProtectionDomain().getCodeSource()
            .getLocation().getPath();

完整堆栈跟踪如下.

java.lang上的java.lang.Class.forName0(本机方法)中的java.lang.ExceptionInInitializerError,javassist上的javassist.runtime.Desc.getClassObject(Desc.java:44)中的java.lang.Class.forName(Class.java:169). run.Desc.getClassType(Desc.java:153)at javassist.runtime.Desc.getType(Desc.java:123)at javassist.runtime.Desc.getType(Desc.java:79)at com.acompany.controller.portfolio .controllerTest.testIncrementalFail(ControllerTest.java:195)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java) :25)在java.lang.reflect.Method.invoke(Method.java:597)在org.junit.internal.runners.TestMethod.invoke(TestMethod.java:66)在org.powermock.modules.junit4.internal. impl.PowerMockJUnit44RunnerDelegateImpl $ PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:307)在org.junit.internal.runners.MethodRoadie $ 2.run(我 thodRoadie.java:86)org.junit.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:94)at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl $ PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)在org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl $ PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:112)在org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl $ PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:73)在Org.junit.internal的org.junm上,在org.junit.internal.runner.MethodRoadie.runTest(MethodRoadie.java:84)的org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl $ PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282) .runners.MethodRoadie.run(MethodRoadie.java:49)at org.powermock.modules.junit4.internal.impl.PowerMo ckJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl $ 1.run (PowerMockJUnit44RunnerDelegateImpl.java:120)在org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)在org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)在org.powermock. modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:118)位于org.powermock.modules的org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:102). junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)在org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)在org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)在org.eclipse.jdt.internal. junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)在org.eclipse.jdt.internal.junit.runner. RemoteTestRunner.main(RemoteTestRunner.java:197)引起:com.acompany.controller.common.AbstractController中的java.lang.NullPointerException.(AbstractController.java:65)... 35更多

Answer 1

那么你可以使用：

 @SuppressStaticInitializationFor({AbstractController.class})

然后，在您的测试用例中，手动设置需要初始化的所有静态字段，包​​括 DEFAULT_FOLDER：

Whitebox.setInternalState(Controller.class, "DEFAULT_FOLDER", "abcd");
Whitebox.setInternalState(Controller.class, "OTHER_FIELD", new Object());

该方法Class<?>.getProtectionDomain()过多地依赖于所使用的类加载器，因此您可能无法使其在使用自己的类加载器的 JUnit/PowerMock 中工作。