当我尝试使用带有JMockit的模拟文件时，我得到一个NullPointerException：

package com.metamolecular.poobah.test;

import java.io.File;

import junit.framework.TestCase;

import mockit.Expectations;

import mockit.Mocked;

public class MockedFileTest extends TestCase

{

@Mocked File file;

public void testMockedFileCanBeUsed1() throws Exception

{

new Expectations()

{

{

file.list();

result = null;

}

};

file.list();

}

public void testMockedFileCanBeUsed2() throws Exception

{

new Expectations()

{

{

file.list();

result = null;

}

};

file.list();

}

}

我的输出是：

[java] 1) testMockedFileCanBeUsed2(com.metamolecular.poobah.test.MockedFileTest)java.lang.NullPointerException

[java] at java.io.FilePermission.init(FilePermission.java:193)

[java] at java.io.FilePermission.(FilePermission.java:249)

[java] at sun.net.www.protocol.file.FileURLConnection.getPermission(FileURLConnection.java:198)

[java] at sun.net.www.protocol.jar.JarFileFactory.getPermission(JarFileFactory.java:124)

[java] at sun.net.www.protocol.jar.JarFileFactory.getCachedJarFile(JarFileFactory.java:94)

[java] at sun.net.www.protocol.jar.JarFileFactory.get(JarFileFactory.java:50)

[java] at sun.net.www.protocol.jar.JarURLConnection.connect(JarURLConnection.java:104)

[java] at sun.net.www.protocol.jar.JarURLConnection.getInputStream(JarURLConnection.java:132)

[java] at java.net.URL.openStream(URL.java:1010)

[java] at java.lang.ClassLoader.getResourceAsStream(ClassLoader.java:1232)

[java] at mockit.internal.ClassFile.readClass(ClassFile.java:55)

[java] at mockit.internal.ClassFile.createClassFileReader(ClassFile.java:44)

[java] at mockit.internal.ClassFile.(ClassFile.java:72)

[java] at mockit.internal.RedefinitionEngine.restoreOriginalDefinition(RedefinitionEngine.java:316)

[java] at mockit.internal.state.MockFixture.restoreAndRemoveRedefinedClasses(MockFixture.java:174)

[java] at mockit.internal.state.SavePoint.restoreClassesRedefinedAfterSavepoint(SavePoint.java:77)

[java] at mockit.internal.state.SavePoint.rollback(SavePoint.java:57)

[java] at mockit.internal.state.SavePoint.rollbackForTestClass(SavePoint.java:89)

[java] at mockit.integration.TestRunnerDecorator.updateTestClassState(TestRunnerDecorator.java:54)

[java] at mockit.integration.junit3.internal.JUnitTestCaseDecorator.runBare(JUnitTestCaseDecorator.java:81)

[java] at com.metamolecular.poobah.test.Main.main(Main.java:45)

[java]

[java] FAILURES!!!

[java] Tests run: 2, Failures: 0, Errors: 1

[java]

只有在调用testMockedFileCanBeUsed2时才会发生错误。如果只运行一个测试，则不会抛出任何错误。我在测试套件中看到了这种行为 - 换句话说，如果我在测试套件中使用一次模拟文件，那么使用模拟文件的其他测试套件也会抛出。

不熟悉JMockit，我可能只是在做一些愚蠢的事情 - 但我还没有看到过我用过的其他模拟对象。

有任何想法吗？