java - 在 Maven test/resources 目录中创建和删除文件

Question

我正在尝试为可以写入和删除文件的 java servlet 编写一些单元测试。我有用于我的开发和生产版本的 config.properties 文件，以及仅在测试期间调用的测试/资源中的文件。我写入一个临时文件，该文件后来被删除。

canceled.filepath=src/test/resources/Cancel.txttemp.filepath=src/test/resources/Cancel_temp.txt

我的问题是 servlet 抛出错误，提示我无法删除临时文件。我认为这是由于权限错误造成的。有没有什么地方可以制作这些文件，以便我的单元测试并拥有写入/删除的完全权限？

谢谢

Answer 1

使用 Junit 4 TemporaryFolder 规则为您管理文件系统交互。

public class MyTestClass {
 //MUST be public
    @Rule
    public TemporaryFolder tempFolder = new TemporaryFolder();

    @Test
    public void test() throws Exception{
   //You can create new files.
    File tmpFile = tempFolder.newFile();
    System.out.println(tmpFile.getAbsolutePath());
    System.out.println(tmpFile.exists());

    //Or new Folders
    File myFolder = tempFolder.newFolder("My_Folder");
    System.out.println(myFolder.getAbsolutePath());
    System.out.println(myFolder.exists());

    //or a combination of them.
    File newFileInMyFolder = tempFolder.newFile("My_Folder\\subfile.txt");
    System.out.println(newFileInMyFolder.getAbsolutePath());
    System.out.println(newFileInMyFolder.exists());

    // The Junit rule uses the system property 'java.io.tempdir' to create them, and it handles the cleanup outside
    // the scope of your test!
    }
}

输出:

    C:\Users\Jeremiah\AppData\Local\Temp\junit4815976615865849247\junit796088998678325697.tmp
true
C:\Users\Jeremiah\AppData\Local\Temp\junit4815976615865849247\My_Folder
true
C:\Users\Jeremiah\AppData\Local\Temp\junit4815976615865849247\My_Folder\subfile.txt
true

After the text executes, the Rule implementation handles all clean-up, as long as the files were created using the Rule.

根据您的问题，您可以在 @Before block 中设置系统属性，然后相信它们存在于 Activity 测试的上下文中。

public class MyServletTest {
    //MUST be public
    @Rule
    public TemporaryFolder tempFolder = new TemporaryFolder();

    @Before
    public void setTestPaths() throws Exception {
        File cancelFile = tempFolder.newFile("Cancel.txt");
        File cancelTemp = tempFolder.newFile("Cancel_temp.txt");

        System.setProperty("canceled.filepath", cancelFile.getAbsolutePath());
        System.setProperty("temp.filepath", cancelTemp.getAbsolutePath());
    }

    @After
    public void restorePaths() {
        //FIXME:  The JVM will be reused, if you have any other tests relying on the system properites they will be getting the values set in the BEFORE block.
    }

    @Test
    public void checkSysVars() {
        String cancelPath = System.getProperty("canceled.filepath");
        String tmpPath = System.getProperty("temp.filepath");

        File cancelFile = new File(cancelPath);
        File cancelTemp = new File(tmpPath);
        System.out.println(cancelFile.getAbsolutePath());
        System.out.println(cancelFile.exists());
        System.out.println(cancelTemp.getAbsolutePath());
        System.out.println(cancelTemp.exists());

    }
}

再次，控制台输出:

C:\Users\Jeremiah\AppData\Local\Temp\junit7380201043103411996\Cancel.txt
true
C:\Users\Jeremiah\AppData\Local\Temp\junit7380201043103411996\Cancel_temp.txt
true