Mockito Stubbing callbacks

Question

我是Mockito的新手。我使用的是mockito 1.9.5。junit 4是与日食开普勒一起来的。当我在下面的junit中运行这个测试时。

<pre><code>
@SuppressWarnings("rawtypes")
    @Test
    public void stubbingCallbacks(){        
        when(mockedList.add(anyString())).thenAnswer(new Answer() {
            public Object answer(InvocationOnMock invocation) {
                Object[] args = invocation.getArguments();
                //Object mock = invocation.getMock();
                return "called with arguments: " + args;
            }
        });
        System.out.println(mockedList.add("a"));
    }
</code></pre>

然后它抛出这个异常

    java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Boolean
        at $java.util.LinkedList$$EnhancerByMockitoWithCGLIB$$2744633c.add()
        at com.mock.Verifying.stubbingCallbacks(Verifying.java:185)
        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.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
        at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
        at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
        at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
        at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
        at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
        at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
        at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
        at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
        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)
    

有人知道为什么它抛出ClassCastException吗?和如何解决这个问题?

非常感谢你的帮助

苏拉

Answer 1

当然:List.add(item)返回boolean，您的答案返回String。

Answer 2

不可能违反您所模拟的方法的返回类型。mockedList.add()的返回值是布尔值，所以模拟也应该是布尔值，而不是"called with arguments: " + args