Tomcat 6: how to delete temporary files after a web method call has ended?

java, jax-ws, tomcat, web-services

Solution

I ran into this same problem. The issue is that the JAX-WS stack manages the file. It is not possible to determine in your code when JAX-WS is done with the file so you do not know when to delete it.

In my case, I am using a DataHandler on my object model rather than a file. MyFileResult would have the following field instead of a file field:

private DataHandler handler;

My solution was to create a customized version of FileDataSource. Instead of returning a FileInputStream to read the contents of the file, I return the following extension of FileInputStream:

private class TemporaryFileInputStream extends FileInputStream {
    public TemporaryFileInputStream(File file) throws FileNotFoundException {
        super(file);
    }

    @Override
    public void close() throws IOException {
        super.close();
        file.delete();
    }
}

Essentially the datasource allows reading only once. After the stream is closed, the file is deleted. Since the JAX-WS stack only reads the file once, it works.

The solution is a bit of a hack but seems to be the best option in this case.

Problem

I have a temporary file with data that's returned as part of a SOAP response via a MTOM binary attachment. I would like to trash it as soon as the method call "ends" (i.e., finishes transferring). What's the best way for me to do this? The best way I can figure out how to do this is to delete them when the session is destroyed, but I'm not sure if there's a more 'immediate' way to do this. FYI, I'm NOT using Axis, I'm using jax-ws, if that matters. UPDATE: I'm not sure the answerers are really understanding the issue. I know how to delete a file in java. My problem is this: ``` @javax.jws.WebService public class MyWebService { ... @javax.jws.WebMethod public MyFileResult getSomeObject() { File mytempfile = new File("tempfile.txt"); MyFileResult result = new MyFileResult(); result.setFile(mytempfile); // sets mytempfile as MTOM attachment // mytempfile.delete() iS WRONG // can't delete mytempfile because it hasn't been returned to the web service client // yet. So how do I remove it? return result; } } ```

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