Mockito 提供了在真实对象上创建spy选项。当调用spy时, 就调用真实对象的实际方法。
语法
//create a spy on actual object calcService = spy(calculator); //perform operation on real object //test the add functionality Assert.assertEquals(mathApplication.add(20.0, 10.0),30.0,0);
例如
步骤1−创建一个称为 CalculatorService 的接口, 以提供数学函数
文件: CalculatorService. java
/**
* 计算相关服务
*/
public interface CalculatorService {
/**
* 加法
*
* @param input1
* @param input2
* @return
*/
public double add(double input1, double input2);
/**
* 减法
*
* @param input1
* @param input2
* @return
*/
public double subtract(double input1, double input2);
/**
* 乘法
*
* @param input1
* @param input2
* @return
*/
public double multiply(double input1, double input2);
/**
* 除法
*
* @param input1
* @param input2
* @return
*/
public double divide(double input1, double input2);
}
步骤2−创建一个 JAVA 类来表示 MathApplication
文件: MathApplication. java
/**
* 数学应用
*/
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);
}
}
步骤3−测试 MathApplication 类
让我们测试 MathApplication 类, 通过注入一个 calculatorService 的模拟。模拟将由 Mockito 创建。
在这里, 我们添加了一个模拟方法调用, add () 到模拟对象when ()。但是在测试过程中, 我们在调用 add () 之前调用了subtract ()。当我们使用 Mockito createStrictMock () 创建一个模拟对象时, 该方法的执行顺序很重要。
文件: MathApplicationTester. java
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.junit.MockitoJUnitRunner;
import static org.mockito.Mockito.spy;
// @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();
Calculator calculator = new Calculator();
calcService = spy(calculator);
mathApplication.setCalculatorService(calcService);
}
@Test
public void testAdd(){
//perform operation on real object
//test the add functionality
Assert.assertEquals(mathApplication.add(20.0, 10.0),30.0,0);
}
class Calculator implements CalculatorService {
@Override
public double add(double input1, double input2) {
return input1 + input2;
}
@Override
public double subtract(double input1, double input2) {
throw new UnsupportedOperationException("Method not implemented yet!");
}
@Override
public double multiply(double input1, double input2) {
throw new UnsupportedOperationException("Method not implemented yet!");
}
@Override
public double divide(double input1, double input2) {
throw new UnsupportedOperationException("Method not implemented yet!");
}
}
}
步骤4−执行测试用例
在C: \ > Mockito_WORKSPACE中创建名为 TestRunner 的 java 类文件以执行测试用例。
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, 如下所示−
C:\Mockito_WORKSPACE>javac CalculatorService.java MathApplication. java MathApplicationTester.java TestRunner.java
现在运行TestRunner以查看结果−
C:\Mockito_WORKSPACE>java TestRunner
验证输出。
true