Question

我在服务中使用以下方法来模拟AWS sqs

@Override
public Message recieveMessage(String queueUrl) {
    Objects.requireNonNull(queueUrl);
    ReceiveMessageRequest request = new ReceiveMessageRequest().withQueueUrl(queueUrl).withMaxNumberOfMessages(1);
    ReceiveMessageResult receiveMessageResult = this.sqsClient.receiveMessage(request);
    // As per the spec, we need to return only one message.
    return receiveMessageResult.getMessages().get(0);
}

@Override
public int getMessageCount(String queueUrl) {
    GetQueueAttributesResult queueAttributes = sqsClient.getQueueAttributes(queueUrl, Arrays.asList("ApproximateNumberOfMessages"));
    return Integer.valueOf(queueAttributes.getAttributes().get("ApproximateNumberOfMessages"));
}

以下是我使用mockito的这些方法的测试用例与NPE失败。

@Test
public void testRecieveMessage() {

    Message message = new Message();
    message.setBody("Message Body");

    List<Message> messages = new ArrayList<>();
    messages.add(message);

    ReceiveMessageResult result = new ReceiveMessageResult();
    result.setMessages(messages);

    when(mock(ReceiveMessageResult.class).getMessages()).thenReturn(messages);
    when(mock(List.class).get(0)).thenReturn(message);
    when(this.amazonSQSClient.receiveMessage(mock(ReceiveMessageRequest.class))).thenReturn(result);

    this.amazonQueueService.recieveMessage(anyString());
    verify(this.amazonSQSClient, times(1)).receiveMessage(mock(ReceiveMessageRequest.class));
    //Assert.assertNotNull(msg);
}

显示java.lang.NullPointerException at com.example.queue.service.impl.AmazonSQSService.recieveMessage（AmazonSQSService.java:46） at com.example.AmazonSQSServiceTest.testRecieveMessage（AmazonSQSServiceTest.java:77） 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）在org.junit.runners.model.FrameworkMethod $ 1.runReflectiveCall（FrameworkMethod.java:50）在org.junit.internal.runners.model.ReflectiveCallable.run（ReflectiveCallable.java:12）在org.junit.runners.model.FrameworkMethod.invokeExplosively（FrameworkMethod.java:47）在org.junit.internal.runners.statements.InvokeMethod.evaluate（InvokeMethod.java:17）在org.junit.internal.runners.statements.RunBefores.evaluate（RunBefores.java:26）在org.junit.runners.ParentRunner.runLeaf（ParentRunner.java:325）在org.junit.runners.BlockJUnit4ClassRunner.runChild（BlockJUnit4ClassRunner.java:78）在org.junit.runners.BlockJUnit4ClassRunner.runChild（BlockJUnit4ClassRunner.java:57）在org.junit.runners.ParentRunner $ 3.run（ParentRunner.java:290）在org.junit.runners.ParentRunner $ 1.schedule（ParentRunner.java:71）在org.junit.runners.ParentRunner.runChildren（ParentRunner.java:288）在org.junit.runners.ParentRunner.access $ 000（ParentRunner.java:58）在org.junit.runners.ParentRunner $ 2.evaluate（ParentRunner.java:268）在org.junit.runners.ParentRunner.run（ParentRunner.java:363）在org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run（JUnit45AndHigherRunnerImpl.java:37）在org.mockito.runners.MockitoJUnitRunner.run（MockitoJUnitRunner.java:62）在org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run（JUnit4TestReference.java:86）在org.eclipse.jdt.internal.junit.runner.TestExecution.run（TestExecution.java:38）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:459）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:678）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run（RemoteTestRunner.java:382）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main（RemoteTestRunner.java:192）

@Test
public void testMessageCount() {
    GetQueueAttributesResult result = new GetQueueAttributesResult();
    result.addAttributesEntry("ApproximateNumberOfMessages", "10");
    List<String> attrs = Arrays.asList("ApproximateNumberOfMessages");
    when(this.amazonSQSClient.getQueueAttributes(anyString(), eq(attrs))).thenReturn(result);
    this.amazonQueueService.getMessageCount(anyString());
}

org.mockito.exceptions.misusing.InvalidUseOfMatchersException：参数匹配器的使用无效！ 2匹配预期，1记录： - ＆GT; at com.example.AmazonSQSServiceTest.testMessageCount（AmazonSQSServiceTest.java:96）

如果匹配器与原始值组合，则可能会发生此异常： //不正确： someMethod（anyObject（），＆＃34; raw String＆＃34;）; 使用匹配器时，所有参数都必须由匹配器提供。例如： //正确： someMethod（anyObject（），eq（＆＃34; matcher by matcher＆＃34;））;

有关更多信息，请参阅Matchers类的javadoc。

at com.example.queue.service.impl.AmazonSQSService.getMessageCount(AmazonSQSService.java:58)
at com.example.AmazonSQSServiceTest.testMessageCount(AmazonSQSServiceTest.java:96)
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 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.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnit45AndHigherRunnerImpl.java:37)
at org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

我错过了什么吗？

Answer 1

以下是您的代码所做的事情：

ReceiveMessageRequest request = new ReceiveMessageRequest().withQueueUrl(queueUrl).withMaxNumberOfMessages(1);
ReceiveMessageResult receiveMessageResult = this.sqsClient.receiveMessage(request);

因此它会创建一个新请求，并将新请求传递给sqsClient.receiveMessage()。

以下是您测试的方式：

when(this.amazonSQSClient.receiveMessage(mock(ReceiveMessageRequest.class))).thenReturn(result);

因此，当使用模拟ReceiveMessageRequest调用result时，您的测试会告诉模拟客户端返回receiveMessage()。

这样才能奏效。模拟ReceiveMessageRequest不等于代码中使用的新请求。你需要做一些像

这样的事情

when(this.amazonSQSClient.receiveMessage(any(ReceiveMessageRequest.class))).thenReturn(result);

因此，无论请求传递给receiveMessage，模拟客户端都会返回结果。

关于你的第二个问题：

this.amazonQueueService.getMessageCount(anyString());

没有意义。您需要使用真实的给定字符串调用您的方法。

Java与mockito失败

1 个答案: