JUnit提供了跟踪代码异常处理的选项,您可以测试代码是否引发期望的异常。 expected 参数与@Test注释一起使用。让无涯教程看看@Test(expected)的作用。
创建测试类
在C:\> JUNIT_WORKSPACE中创建一个要测试的Java类,例如MessageUtil.java。
在printMessage()方法内添加错误条件。
/* * 此类在控制台上打印给定的消息。 */public class MessageUtil {
private String message;
//构造函数 //@param message to be printed public MessageUtil(String message){ this.message = message; }
//打印消息 public void printMessage(){ System.out.println(message); int a = 0; int b = 1/a; }
//添加“Hi!”到消息 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 TestJunit.java 的Java测试类。将一个预期的异常ArithmeticException添加到testPrintMessage()测试用例。
在C:\> JUNIT_WORKSPACE中创建一个名为TestJunit.java的Java类文件。
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()); } }
创建测试运行类
在C:\> JUNIT_WORKSPACE中创建一个名为TestRunner.java的Java类文件以执行测试用例。
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);
</span><span class="kwd">for</span><span class="pln"> </span><span class="pun">(</span><span class="typ">Failure</span><span class="pln"> failure </span><span class="pun">:</span><span class="pln"> result</span><span class="pun">.</span><span class="pln">getFailures</span><span class="pun">())</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
</span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="pln">failure</span><span class="pun">.</span><span class="pln">toString</span><span class="pun">());</span><span class="pln">
</span><span class="pun">}</span><span class="pln">
</span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="pln">result</span><span class="pun">.</span><span class="pln">wasSuccessful</span><span class="pun">());</span><span class="pln">
}
}
使用javac编译MessageUtil,测试用例和测试运行器类。
C:\JUNIT_WORKSPACE>javac MessageUtil.java TestJunit.java TestRunner.java
现在运行Test 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。将通过testPrintMessage()测试用例。
Inside testPrintMessage() Robert Inside testSalutationMessage() Hi!Robert true