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How to Capture System.err and System.out

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How to Capture System.err and System.out

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Sometimes you need to capture the text being written to a PrintStream by a 3rd party component. Here it is a simple solution for out and err PrintStreams:

//System.out
PipedOutputStream pipeOut = new PipedOutputStream();
PipedInputStream pipeIn = new PipedInputStream(pipeOut);
System.setOut(new PrintStream(pipeOut));
// now read from pipeIn

//System.err
PipedOutputStream pipeOut = new PipedOutputStream();
PipedInputStream pipeIn = new PipedInputStream(pipeOut);
System.setErr(new PrintStream(pipeOut));
// now read from pipeIn

 From http://e-blog-java.blogspot.com/2011/03/how-to-capture-systemout-and-systemerr.html

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