Mockito – 有序验证

Mockito 提供了 Inorder 类，它负责处理模拟将在其操作的适当过程中进行的方法调用的顺序。

句法

//create an inOrder verifier for a single mock
InOrder inOrder = inOrder(calcService);

//following will make sure that add is first called then subtract is called.
inOrder.verify(calcService).add(20.0,10.0);
inOrder.verify(calcService).subtract(20.0,10.0);

例子

Step 1 – 创建一个名为 CalculatorService 的接口来提供数学函数

文件：CalculatorService.java

public interface CalculatorService {
   public double add(double input1, double input2);
   public double subtract(double input1, double input2);
   public double multiply(double input1, double input2);
   public double divide(double input1, double input2);
}

第 2 步 – 创建一个 JAVA 类来表示 MathApplication

文件：MathApplication.java

public class MathApplication {
   private CalculatorService calcService;

   public void setCalculatorService(CalculatorService calcService){
      this.calcService = calcService;
   }
   
   public double add(double input1, double input2){
      return calcService.add(input1, input2);		
   }
   
   public double subtract(double input1, double input2){
      return calcService.subtract(input1, input2);
   }
   
   public double multiply(double input1, double input2){
      return calcService.multiply(input1, input2);
   }
   
   public double divide(double input1, double input2){
      return calcService.divide(input1, input2);
   }
}

第 3 步 – 测试 MathApplication 类

让我们测试 MathApplication 类，通过在其中注入一个计算器服务的模拟。Mock 将由 Mockito 创建。

在这里，我们通过 when() 向模拟对象添加了两个模拟方法调用，add() 和subtract()。但是在测试过程中，我们在调用 add() 之前调用了消减()。当我们使用 Mockito 创建模拟对象时，方法的执行顺序无关紧要。使用 InOrder 类，我们可以确保调用顺序。

文件：MathApplicationTester.java

import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.inOrder;

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InOrder;
import org.mockito.runners.MockitoJUnitRunner;

// @RunWith attaches a runner with the test class to initialize the test data
@RunWith(MockitoJUnitRunner.class)
public class MathApplicationTester {
	
   private MathApplication mathApplication;
   private CalculatorService calcService;

   @Before
   public void setUp(){
      mathApplication = new MathApplication();
      calcService = mock(CalculatorService.class);
      mathApplication.setCalculatorService(calcService);
   }

   @Test
   public void testAddAndSubtract(){

      //add the behavior to add numbers
      when(calcService.add(20.0,10.0)).thenReturn(30.0);

      //subtract the behavior to subtract numbers
      when(calcService.subtract(20.0,10.0)).thenReturn(10.0);

      //test the add functionality
      Assert.assertEquals(mathApplication.add(20.0, 10.0),30.0,0);

      //test the subtract functionality
      Assert.assertEquals(mathApplication.subtract(20.0, 10.0),10.0,0);

      //create an inOrder verifier for a single mock
      InOrder inOrder = inOrder(calcService);

      //following will make sure that add is first called then subtract is called.
      inOrder.verify(calcService).subtract(20.0,10.0);
      inOrder.verify(calcService).add(20.0,10.0);

   }
}

第 4 步 – 执行测试用例

在C:\> Mockito_WORKSPACE 中创建一个名为 TestRunner 的 java 类文件来执行测试用例。

文件：TestRunner.java

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(MathApplicationTester.class);
      
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      
      System.out.println(result.wasSuccessful());
   }
}  	

步骤 5 – 验证结果

使用javac编译器编译类如下 –

C:\Mockito_WORKSPACE>javac CalculatorService.java MathApplication.
   java MathApplicationTester.java TestRunner.java

现在运行 Test Runner 以查看结果 –

C:\Mockito_WORKSPACE>java TestRunner

验证输出。

testAddAndSubtract(MathApplicationTester): 
Verification in order failure
Wanted but not invoked:
calculatorService.add(20.0, 10.0);
-> at MathApplicationTester.testAddAndSubtract(MathApplicationTester.java:48)
Wanted anywhere AFTER following interaction:
calculatorService.subtract(20.0, 10.0);
-> at MathApplication.subtract(MathApplication.java:13)
false