我想为Android应用程序中的静态方法编写一个单元测试。为此，我使用Mockito和PowerMock。
在Android文件夹test(myproject/app/src/test/java/com/myproject/android/)中，我有这个单元测试：
@RunWith(PowerMockRunner.class)
@PrepareForTest(StringUtil.class)
public class StringUtilTest {
@Test
public void isCorrectEmailStub() {
mockStatic(StringUtil.class);
String INCORRECT_EMAIL_TO_CHECK = "incorrect_email_some.com";
when(StringUtil.isCorrectEmail(INCORRECT_EMAIL_TO_CHECK)).thenReturn(true);
assertThat(StringUtil.isCorrectEmail(INCORRECT_EMAIL_TO_CHECK), is(true));
}
}
这是我build.gradle：
android {
defaultConfig {
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
}
dependencies {
testCompile 'junit:junit:4.12'
testCompile 'org.powermock:powermock-api-mockito:1.6.6'
testCompile 'org.powermock:powermock-module-junit4:1.6.6'
testCompile "org.mockito:mockito-core:2.7.22"
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
androidTestCompile "org.mockito:mockito-android:2.7.21"
}
项目构建成功，但是当我尝试运行测试isCorrectEmailStub时，出现此错误：
线程"main"中的异常 java.lang.NoClassDefFoundError： org/mockito/exceptions/Reporter at sun.reflect.GeneratedSerializationConstructorAccessor5.newInstance(Unknown 来源) at java.lang.reflect.Constructor.newInstance(Constructor.java：423) at org.objenesis.instantiator.sun.SunReflectionFactoryInstantiator.newInstance(SunReflectionFactoryInstantiator.java：48) at org.powermock.reflect.internal.WhiteboxImpl.newInstance(WhiteboxImpl.java：251) at org.powermock.reflect.Whitebox.newInstance(Whitebox.java：139) at org.powermock.api.extension.reporter.AbstractMockingFrameworkReporterFactory.getInstanceForClassLoader(AbstractMockingFrameworkReporterFactory.java：41) at org.powermock.api.extension.reporter.AbstractMockingFrameworkReporterFactory.create(AbstractMockingFrameworkReporterFactory.java：35) at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.getMockingFrameworkReporter(JUnit4TestSuiteChunkerImpl.java：140) at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java：119) 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.junit.runner.JUnitCore.run(JUnitCore.java：137) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java：117) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java：42) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java：262) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java：84) 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.AppMain.main(AppMain.java：147) 原因：java.lang.ClassNotFoundException： org.mockito.exceptions.Reporter 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) at org.powermock.core.classloader.MockClassLoader.loadModifiedClass(MockClassLoader.java：190) at org.powermock.core.classloader.DeferSupportingClassLoader.loadClass1(DeferSupportingClassLoader.java：77) at org.powermock.core.classloader.DeferSupportingClassLoader.loadClass(DeferSupportingClassLoader.java：67) at java.lang.ClassLoader.loadClass(ClassLoader.java：357)
为什么会出现此错误，如何防止此错误？
仅适用于 Mockito 版本 <2.0。这项工作：
testCompile 'org.powermock:powermock-api-mockito:1.6.6'
testCompile 'org.powermock:powermock-module-junit4:1.6.6'
testCompile "org.mockito:mockito-core:1.10.19"