使用 junit 对 java 程序做单元测试

创建一个测试文件名为 TestFruit.java

 

import junit.framework.TestCase;

public class TestFruit extends TestCase{
	public void testFruit() throws Exception {
		assertEquals(1, 2);
	}
}

 

具体的测试方法 testFruit 后面跟了这样一句：

throws Exception

 

意识是，该方法可能产生异常，调用此方法的代码需要做好异常处理。

也就是显式地说“我会抛出异常，注意处理啊！”

 

而不加这句，通常异常处理就在该方法内部进行了，调用者就可以放心大胆地使用了。

 

运行时，会报出该异常：

junit.framework.AssertionFailedError: expected:<1> but was:<2>

at junit.framework.Assert.fail(Assert.java:47)

at junit.framework.Assert.failNotEquals(Assert.java:283)

at junit.framework.Assert.assertEquals(Assert.java:64)

at junit.framework.Assert.assertEquals(Assert.java:195)

at junit.framework.Assert.assertEquals(Assert.java:201)

at TestFruit.testFruit(TestFruit.java:5)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at junit.framework.TestCase.runTest(TestCase.java:168)

at junit.framework.TestCase.runBare(TestCase.java:134)

at junit.framework.TestResult$1.protect(TestResult.java:110)

at junit.framework.TestResult.runProtected(TestResult.java:128)

at junit.framework.TestResult.run(TestResult.java:113)

at junit.framework.TestCase.run(TestCase.java:124)

at junit.framework.TestSuite.runTest(TestSuite.java:232)

at junit.framework.TestSuite.run(TestSuite.java:227)

at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:83)

at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)

at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)