Question

I have a failure in my JUnit testing testing trace.
The error is java.lang.NullPointerException and it occurs into these line of code:

    @AfterClass
public static void after()
{
    stopServer();
}

and

static void stopServer()
{
    ftp.stop();
}

What I want to do is to have my @AfterClass to stop my fakeFTPServer, initiate into the @BeforeClass

    @BeforeClass
public static void before()
{
    FakeFtpServer ftp = new FakeFtpServer();

    ftp.addUserAccount(new UserAccount("user", "password", "c:\\data"));
    FileSystem fileSystem = new WindowsFakeFileSystem();
    fileSystem.add(new DirectoryEntry("c:\\data"));
    fileSystem.add(new FileEntry("c:\\data\\file1.txt", "abcdef 1234567890"));
    fileSystem.add(new FileEntry("c:\\data\\run.exe"));
    ftp.setFileSystem(fileSystem);

    ftp.start();

    ftpClient = new FTPClient();}

Thanks for your help!

Answer 1

It looks like you have more than one variable named ftp.

This is one of them:

FakeFtpServer ftp = new FakeFtpServer();

This ftp is local to before() and therefore can’t be the variable referenced in stopServer(). The latter must be using a different variable named ftp, which nevers get initialized. At a guess, that other ftp is a static member of your class.

I suspect the above line was meant to read:

ftp = new FakeFtpServer();