Java 使用自定义参数匹配器第二次调用Mockito.when时的NPE
你好 假设我有一个接口。接口有一个方法,该方法接受某些类的一个或两个实例。在单元测试类中,我模拟这个接口,并希望用如下逻辑模拟它:Java 使用自定义参数匹配器第二次调用Mockito.when时的NPE,java,unit-testing,mockito,junit4,Java,Unit Testing,Mockito,Junit4,你好 假设我有一个接口。接口有一个方法,该方法接受某些类的一个或两个实例。在单元测试类中,我模拟这个接口,并希望用如下逻辑模拟它: 如果参数与template1匹配,则返回值1 如果参数与template2匹配,则返回值2 当我只模拟第一个案例时,测试运行平稳。当我添加第二种情况(与第一种情况一起)时,测试会与NPE一起崩溃,如: java.lang.NullPointerException at org.some.pkg.TestTest$ArgMatcher.matches(TestTest
java.lang.NullPointerException
at org.some.pkg.TestTest$ArgMatcher.matches(TestTest.java:54)
at org.some.pkg.TestTest$ArgMatcher.matches(TestTest.java:43)
at org.mockito.internal.invocation.TypeSafeMatching.apply(TypeSafeMatching.java:24)
at org.mockito.internal.invocation.MatcherApplicationStrategy.forEachMatcherAndArgument(MatcherApplicationStrategy.java:83)
at org.mockito.internal.invocation.InvocationMatcher.argumentsMatch(InvocationMatcher.java:152)
at org.mockito.internal.invocation.InvocationMatcher.matches(InvocationMatcher.java:81)
at org.mockito.internal.stubbing.InvocationContainerImpl.findAnswerFor(InvocationContainerImpl.java:91)
at org.mockito.internal.handler.MockHandlerImpl.handle(MockHandlerImpl.java:87)
at org.mockito.internal.handler.NullResultGuardian.handle(NullResultGuardian.java:29)
at org.mockito.internal.handler.InvocationNotifierHandler.handle(InvocationNotifierHandler.java:35)
at org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.doIntercept(MockMethodInterceptor.java:63)
at org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.doIntercept(MockMethodInterceptor.java:49)
at org.mockito.internal.creation.bytebuddy.MockMethodInterceptor$DispatcherDefaultingToRealMethod.interceptAbstract(MockMethodInterceptor.java:128)
at org.some.pkg.Interface$MockitoMock$1549778145.callMe(Unknown Source)
at org.some.pkg.TestTest.test(TestTest.java:29)
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.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.DefaultInternalRunner$1.run(DefaultInternalRunner.java:79)
at org.mockito.internal.runners.DefaultInternalRunner.run(DefaultInternalRunner.java:85)
at org.mockito.internal.runners.StrictRunner.run(StrictRunner.java:39)
at org.mockito.junit.MockitoJUnitRunner.run(MockitoJUnitRunner.java:163)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
[MockitoHint] TestTest.test (see javadoc for MockitoHint):
[MockitoHint] 1. Unused... -> at org.some.pkg.TestTest.test(TestTest.java:24)
[MockitoHint] ...args ok? -> at org.some.pkg.TestTest.test(TestTest.java:29)
Process finished with exit code 255
下面是一个设置示例
文件:Interface.java——模拟的接口
package org.some.pkg;
公共接口{
公共类Arg{
私有字符串str;
私人INTV;
公共参数(字符串str,int v){
this.str=str;
这个,v=v;
}
公共字符串getStr(){
返回str;
}
公共int getV(){
返回v;
}
}
int callMe(Arg a1,Arg a2);
}
文件:TestedClass.java——一些委托类(实际上是经过测试的一个)
package org.some.pkg;
导入org.springframework.beans.factory.annotation.Autowired;
公共类测试类{
@自动连线
接口代表;
int callMe(Interface.Arg a1,Interface.Arg a2){
INTX=委托调用(a1,a2);
返回x*2;
}
}
文件:TestTest.java——测试
package org.some.pkg;
导入org.junit.Assert;
导入org.junit.Test;
导入org.junit.runner.RunWith;
导入org.mockito.ArgumentMatcher;
导入org.mockito.InjectMocks;
导入org.mockito.Mock;
导入org.mockito.junit.MockitoJUnitRunner;
导入静态org.mockito.ArgumentMatchers.argThat;
导入静态org.mockito.mockito.when;
@RunWith(MockitoJUnitRunner.class)
公共类测试{
@嘲弄
专用接口iface;
@注射模拟
私有TestedClass TestedClass;
@试验
公开无效测试(){
//当-1
什么时候打电话给我(
argThat(新的ArgMatcher(“start1”,10)),
argThat(新的ArgMatcher(“start2”,5))
)).然后返回(10);
//何时-2
什么时候打电话给我(
argThat(新的ArgMatcher(“start3”,5)),
argThat(新的ArgMatcher(“start4”,2))
)).然后返回(3);
//试验
int v=testedClass.callMe(
新的Interface.Arg(“start1后缀”,3),
Arg(“start2,后缀”,4));
System.out.println(“V=”+V);
Assert.assertEquals(20,v);
}
类ArgMatcher实现ArgumentMatcher{
私有最终字符串开始;
私有最终整数阈值;
公共ArgMatcher(字符串开始,整数阈值){
this.start=start;
这个阈值=阈值;
}
@凌驾
公共布尔匹配(Interface.Arg参数){
返回argument.getV()
如果我在when-2块中注释掉,则测试运行良好且平稳。否则,我看到一个NPE没有任何明显的原因
Mockito的版本是2.24.0
JUnit是版本4
更新:第二次调用Mockito的斗争。当
知道在一个单元测试中可以多次调用mock方法时。好吧,我找到了一个解决方法,使用when(mock.callMe(any(Arg.class)、any(Arg.class))。然后是Answer(新答案{…})代码>好吧,我已经找到了一个解决方法,使用when(mock.callMe(any(Arg.class)、any(Arg.class)).thenAnswer(new-Answer{…})使用Mockito 2.28.2和3.1.0编码>:
面临类似的问题,解决方案是按照@Morfic提出的方法进行重写(假设Mockito是静态导入的):
与:
然而,我不知道或解释为什么第一个失败,第二个工作正常
JUnit 4测试用例以显示故障和工作选项:
class MyBean{
public Integer id;
public String name;
public MyBean(int id, String name) {
this.id = id;
this.name = name;
}
}
interface MyService{
Integer measure(MyBean myBean);
}
@Test
public void testThatFailsWithNPE(){
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")))).thenReturn(123);
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")))).thenReturn(321);
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}
@Test
public void testThatPasses(){
doReturn(123).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")));
doReturn(321).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")));
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}
对于Mockito 2.28.2和3.1.0:
面临类似的问题,解决方案是按照@Morfic提出的方法进行重写(假设Mockito是静态导入的):
与:
然而,我不知道或解释为什么第一个失败,第二个工作正常
JUnit 4测试用例以显示故障和工作选项:
class MyBean{
public Integer id;
public String name;
public MyBean(int id, String name) {
this.id = id;
this.name = name;
}
}
interface MyService{
Integer measure(MyBean myBean);
}
@Test
public void testThatFailsWithNPE(){
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")))).thenReturn(123);
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")))).thenReturn(321);
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}
@Test
public void testThatPasses(){
doReturn(123).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")));
doReturn(321).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")));
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}
空指针是一个遗憾,在需要的地方使用可选的。好吧,我在可能的地方这样做。然而,我找不到任何理由说明mockito在第二次调用时抛出和NPE。这太糟糕了……更新:第二次调用Mockito的斗争。当是一个知识时,mocked方法可以在一个单元测试中被多次调用。我还没有挖掘出源代码来真正理解为什么,我也没有在中找到很多,但基本上与。Szczepan(Mockito的作者)也没有提供任何见解。简而言之,将第二个when
更改为doReturn(3).when(iface).callMe(…)代码>你会很好的。请注意,除非您实际使用第二个stubing,否则您的测试将通过,但您将在测试时得到一个不必要的stubbingException
end@Morfic这肯定是一个答案…空指针是一个耻辱,在需要的地方使用可选的。好吧,我在可能的地方这样做。然而,我找不到任何理由说明mockito在第二次调用时抛出和NPE。这太糟糕了……更新:第二次调用Mockito的斗争。当是一个知识时,mocked方法可以在一个单元测试中被多次调用。我还没有挖掘出源代码来真正理解为什么,我也没有在中找到很多,但基本上与。Szczepan(Mockito的作者)也没有提供任何见解。简而言之,将第二个when
更改为doReturn(3).when(iface).callMe(…)代码>你会很好的。请注意,除非您实际使用第二个stubb
class MyBean{
public Integer id;
public String name;
public MyBean(int id, String name) {
this.id = id;
this.name = name;
}
}
interface MyService{
Integer measure(MyBean myBean);
}
@Test
public void testThatFailsWithNPE(){
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")))).thenReturn(123);
when(myService.measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")))).thenReturn(321);
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}
@Test
public void testThatPasses(){
doReturn(123).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 123) && Objects.equals(mb.name, "123")));
doReturn(321).when(myService).measure(argThat((mb) -> Objects.equals(mb.id, 321) && Objects.equals(mb.name, "321")));
assertEquals(Integer.valueOf(123), myService.measure(new MyBean(123, "123")));
assertEquals(Integer.valueOf(321), myService.measure(new MyBean(321, "321")));
assertEquals(Integer.valueOf(0), myService.measure(new MyBean(777, "777")));
}