JUnit提供了跟踪代码异常处理的选项.您可以测试代码是否抛出所需的异常. 预期参数与@Test注释一起使用.让我们看看@Test(预期)在行动.
创建一个类
创建一个要测试的java类,比如说, MessageUtil在C:\> JUNIT_WORKSPACE中的.java .
在printMessage()方法中添加错误条件.
/** This class prints the given message on console.*/public class MessageUtil { private String message; //Constructor //@param message to be printed public MessageUtil(String message){ this.message = message; } // prints the message public void printMessage(){ System.out.println(message); int a = 0; int b = 1/a; } // add "Hi!" to the message public String salutationMessage(){ message = "Hi!" + message; System.out.println(message); return message; } }
创建测试用例类
创建一个名为
在C:\> JUNIT_WORKSPACE中创建名为 TestJunit.java 的java类文件./p>
import org.junit.Test;import org.junit.Ignore;import static org.junit.Assert.assertEquals;public class TestJunit { String message = "Robert"; MessageUtil messageUtil = new MessageUtil(message); @Test(expected = ArithmeticException.class) public void testPrintMessage() { System.out.println("Inside testPrintMessage()"); messageUtil.printMessage(); } @Test public void testSalutationMessage() { System.out.println("Inside testSalutationMessage()"); message = "Hi!" + "Robert"; assertEquals(message,messageUtil.salutationMessage()); }}
创建测试运行器类
创建一个名为
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(TestJunit.class); for (Failure failure : result.getFailures()) { System.out.println(failure.toString()); } System.out.println(result.wasSuccessful()); }}
使用javac编译MessageUtil,Test case和Test Runner类.
C:\ JUNIT_WORKSPACE> javac MessageUtil.java TestJunit.java TestRunner.java
现在运行测试Runner,它将运行在提供的Test Case类中定义的测试用例.
C:\ JUNIT_WORKSPACE> java TestRunner
验证输出. testPrintMessage()测试用例将被传递.
Inside testPrintMessage()RobertInside testSalutationMessage()Hi!Roberttrue