Powermock无法模拟MysqlConnect

时间:2013-11-13 07:37:33

标签: java unit-testing mockito powermock

这是我的Mysql类:

public class MysqlConnection {

    public Connection MysqlConnect() {
        String url = "jdbc:mysql://localhost:3306/";
        String dbName = "dashboard";
        String driver = "com.mysql.jdbc.Driver";
        String userName = "root";
        String passwd = "";
        Connection conn = null;
        try {
            Class.forName(driver);
            conn = DriverManager.getConnection(url+dbName,userName,passwd);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return conn;
    }
}

我的PowerMockito测试类是这样的:

@RunWith(PowerMockRunner.class)
@PowerMockIgnore("javax.management.*")
@PrepareForTest(Class.class)
public class MysqlConnectionTest {

    @Test(expected = ClassNotFoundException.class)
    public void MysqlConnectiontest() {
        PowerMockito.mockStatic(Class.class);
        try {
            when(Class.forName(Mockito.anyString())).thenThrow(new ClassNotFoundException("error message"));
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        obj.MysqlConnect();
    }
}

错误的Stacktrace是:

java.lang.AssertionError: Expected exception: java.lang.ClassNotFoundException
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:314)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:86)
at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:94)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:296)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:112)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:73)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:284)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:84)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:209)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:148)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:122)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:102)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:42)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
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)

该程序不是模拟任何代码行,而是从实际的MySQLConnect函数执行代码。它正在利用实际的驱动程序。如果我从@Test中删除了预期的部分,则测试成功。也就是说,没有进行模拟,加载了驱动程序以及所有内容。

1 个答案:

答案 0 :(得分:3)

您不能使用PowerMockito或依赖于运行时字节代码修改的任何其他模拟框架来模拟java.lang.Class。 原因是当mockito代理正在操纵(检测)应该被模拟的类时,已经加载了这些类。

为什么不改为嘲笑你的MysqlConnection课程?在那里你可以窥探你的MysqlConnect方法并返回一个模拟的连接。