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Java: mock multipartfile in unit test

I am trying to mock a MultipartFile and I want to create the mock with a stream that I create in the test

I've tries with a file without much luck either. Here is what I have tried so far

FileInputStream stream = new 
FileInputStream("MOCK_file.xlsm");
MultipartFile f1 = new MockMultipartFile("file1",stream);
MultipartFile[] files = {f1};
return files;

I get a fileNotFoundException. Where should I put my file in my Maven project so the unit tests can find the file?

-- OR --

How do I just create a stream in code without the use of a file?

Solution

  • How do I just create a stream in code without the use of a file?

    You could use a ByteArrayInputStream to inject mock data. It's pretty straightforward for a small amount of data:

    byte[] data = new byte[] {1, 2, 3, 4};
InputStream stream = new ByteArrayInputStream(data);

    Otherwise, you need to figure out what directory is your code running from, which is something that depends on how it's being run. To help with that you could print the user.dir system property, which tells you the current directory:

    System.out.println(System.getProperty("user.dir"));

    Alternatively, you can use a full path, rather than a relative one to find the file.