我有一个类,我想使用调用另一个类的私有(private)方法的公共(public)方法来测试它。当我尝试调用同一个类的私有(private)方法时,一切正常。当我尝试模拟从被测类调用的另一个私有(private)方法时,就会出现问题。以下是测试类的代码示例。
@RunWith(PowerMockRunner.class)
@PrepareForTest({CodeWithPrivateMethod.class,CodeWithAnotherPrivateMethod.class})
public class CodeWithPrivateMethodTest {
@Test
public void when_gambling_is_true_then_always_explode() throws Exception {
CodeWithPrivateMethod spy = PowerMockito.spy(new CodeWithPrivateMethod());
CodeWithAnotherPrivateMethod codeWithAnotherPrivateMethod = PowerMockito.spy(new CodeWithAnotherPrivateMethod());
/*when(codeWithAnotherPrivateMethod, method(CodeWithAnotherPrivateMethod.class, "doTheGame", String.class))
.withArguments(anyString())
.thenReturn(true);*/
PowerMockito.when(codeWithAnotherPrivateMethod, "doTheGame", anyString()).thenReturn(true);
//PowerMockito.doReturn(true).when(codeWithAnotherPrivateMethod, "doTheGamble", anyString(),anyInt());
spy.meaningfulPublicApi();
}
}
以下是被测类的代码示例
import java.util.Random;
public class CodeWithPrivateMethod {
CodeWithAnotherPrivateMethod anotherPrivateMethod = new CodeWithAnotherPrivateMethod();
public void meaningfulPublicApi() {
if (anotherPrivateMethod.doTheGame("Whatever")) {
System.out.println("kaboom");
}
}
}
以下是从被测类调用的类的代码示例
import java.util.Random;
public class CodeWithAnotherPrivateMethod {
public boolean doTheGame(String string) {
return doTheGamble("Whatever", 1 << 3);
}
private boolean doTheGamble(String whatever, int binary) {
Random random = new Random(System.nanoTime());
boolean gamble = random.nextBoolean();
return gamble;
}
}
所以我的问题是如何成功模拟 CodeWithAnotherPrivateMethod 类的 doTheGamble() 方法以使其始终返回 true?
最佳答案
这里的问题是,尽管您在测试中创建了 CodeWithAnotherPrivateMethod
的 spy ,但在 CodeWithPrivateMethod
中创建了 CodeWithAnotherPrivateMethod
的新实例。所以,实际上你没有使用你的模拟。
CodeWithAnotherPrivateMethod anotherPrivateMethod = new CodeWithAnotherPrivateMethod();
为了避免这种情况,您可以在创建新实例时强制返回 CodeWithAnotherPrivateMethod 模拟。您可以使用 PowerMockito whenNew()
有能力做到这一点。
示例:
PowerMockito.whenNew(CodeWithAnotherPrivateMethod.class).withAnyArguments().thenReturn(codeWithAnotherPrivateMethod);
最后,你的测试应该是这样的:
@Test
public void when_gambling_is_true_then_always_explode() throws Exception {
// Spy CodeWithAnotherPrivateMethod and force return true when doTheGamble is called
CodeWithAnotherPrivateMethod codeWithAnotherPrivateMethod = PowerMockito.spy(new CodeWithAnotherPrivateMethod());
PowerMockito.doReturn(true).when(codeWithAnotherPrivateMethod, "doTheGamble", Mockito.anyString(), Mockito.anyInt());
// Return your mock when a new instance of CodeWithAnotherPrivateMethod is created.
PowerMockito.whenNew(CodeWithAnotherPrivateMethod.class).withAnyArguments().thenReturn(codeWithAnotherPrivateMethod);
CodeWithPrivateMethod spy = PowerMockito.spy(new CodeWithPrivateMethod());
spy.meaningfulPublicApi();
}
希望有帮助。
关于java - 如何使用PowerMock模拟除被测类之外的另一个类的私有(private)方法?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35450741/