我还有最后一节课,大概是这样的:

public final class RainOnTrees{

   public void startRain(){

        // some code here
   }
}

我在其他一些类中使用这个类,像这样:

public class Seasons{

   RainOnTrees rain = new RainOnTrees();

   public void findSeasonAndRain(){

        rain.startRain();

    }
}

在我的JUnit测试类Seasons.java中,我想模拟RainOnTrees类。我怎么能用Mockito做到这一点?


当前回答

如果你正在使用Mockito2,这可以做到,新的孵化功能支持模拟最终类和方法。

需要注意的要点: 1. 创建一个名为“org.mockito.plugins”的简单文件。并将其放在名为mockito-extensions的文件夹中。这个文件夹应该在类路径上可用。 2. 上面创建的文件内容应该是一行,如下所示: mock-maker-inline

为了激活mockito扩展机制并使用此选择加入特性,需要执行上述两个步骤。

示例类如下:-

FinalClass.java

public final class FinalClass {

public final String hello(){
    System.out.println("Final class says Hello!!!");
    return "0";
}

}

Foo.java

public class Foo {

public String executeFinal(FinalClass finalClass){
    return finalClass.hello();
}

}

FooTest.java

public class FooTest {

@Test
public void testFinalClass(){
    // Instantiate the class under test.
    Foo foo = new Foo();

    // Instantiate the external dependency
    FinalClass realFinalClass = new FinalClass();

    // Create mock object for the final class. 
    FinalClass mockedFinalClass = mock(FinalClass.class);

    // Provide stub for mocked object.
    when(mockedFinalClass.hello()).thenReturn("1");

    // assert
    assertEquals("0", foo.executeFinal(realFinalClass));
    assertEquals("1", foo.executeFinal(mockedFinalClass));

}

}

希望能有所帮助。

完整的文章呈现在这里嘲笑不可嘲笑的。

其他回答

只有在Mockito v2中才可以模拟final/static类/方法。

添加到你的gradle文件:

testImplementation 'org.mockito:mockito-inline:2.13.0'

这是不可能与Mockito v1,从Mockito常见问题:

Mockito的局限性是什么 需要java1.5 + 不能模拟最终类 ...

Mockito 2现在支持final类和方法!

但就目前而言,这只是一个“孵化”功能。它需要一些步骤来激活它,这些步骤在Mockito 2中的新内容中描述:

Mocking of final classes and methods is an incubating, opt-in feature. It uses a combination of Java agent instrumentation and subclassing in order to enable mockability of these types. As this works differently to our current mechanism and this one has different limitations and as we want to gather experience and user feedback, this feature had to be explicitly activated to be available ; it can be done via the mockito extension mechanism by creating the file src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker containing a single line: mock-maker-inline After you created this file, Mockito will automatically use this new engine and one can do : final class FinalClass { final String finalMethod() { return "something"; } } FinalClass concrete = new FinalClass(); FinalClass mock = mock(FinalClass.class); given(mock.finalMethod()).willReturn("not anymore"); assertThat(mock.finalMethod()).isNotEqualTo(concrete.finalMethod()); In subsequent milestones, the team will bring a programmatic way of using this feature. We will identify and provide support for all unmockable scenarios. Stay tuned and please let us know what you think of this feature!

请看JMockit。它有大量的文档和示例。这里你有一个解决你的问题的例子(为了简化,我添加了构造函数到Seasons注入模拟RainOnTrees实例):

package jmockitexample;

import mockit.Mocked;
import mockit.Verifications;
import mockit.integration.junit4.JMockit;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(JMockit.class)
public class SeasonsTest {

    @Test
    public void shouldStartRain(@Mocked final RainOnTrees rain) {
        Seasons seasons = new Seasons(rain);

        seasons.findSeasonAndRain();

        new Verifications() {{
            rain.startRain();
        }};
    }

    public final class RainOnTrees {
        public void startRain() {
            // some code here
        }

    }

    public class Seasons {

        private final RainOnTrees rain;

        public Seasons(RainOnTrees rain) {
            this.rain = rain;
        }

        public void findSeasonAndRain() {
            rain.startRain();
        }

    }
}

我认为原则上你需要多想想。相反,你最终类使用他的接口和模拟接口。

:

 public class RainOnTrees{

   fun startRain():Observable<Boolean>{

        // some code here
   }
}

add

interface iRainOnTrees{
  public void startRain():Observable<Boolean>
}

并模拟你的界面:

 @Before
    fun setUp() {
        rainService= Mockito.mock(iRainOnTrees::class.java)

        `when`(rainService.startRain()).thenReturn(
            just(true).delay(3, TimeUnit.SECONDS)
        )

    }

实际上有一种方法,我用来监视的。只有满足两个前提条件,它才会为你工作:

使用某种DI注入final类的实例 Final类实现了一个接口

请回顾Effective Java中的第16项。你可以创建一个包装器(不是final)并将所有调用转发给final类的实例:

public final class RainOnTrees implement IRainOnTrees {
    @Override public void startRain() { // some code here }
}

public class RainOnTreesWrapper implement IRainOnTrees {
    private IRainOnTrees delegate;
    public RainOnTreesWrapper(IRainOnTrees delegate) {this.delegate = delegate;}
    @Override public void startRain() { delegate.startRain(); }
}

现在你不仅可以模仿你的最后一个类,还可以监视它:

public class Seasons{
    RainOnTrees rain;
    public Seasons(IRainOnTrees rain) { this.rain = rain; };
    public void findSeasonAndRain(){
        rain.startRain();
   }
}

IRainOnTrees rain = spy(new RainOnTreesWrapper(new RainOnTrees()) // or mock(IRainOnTrees.class)
doNothing().when(rain).startRain();
new Seasons(rain).findSeasonAndRain();