Hiding System.out.print calls of a class

Question

I'm using a java library (jar file). The author of the file put in a bunch of System.out.print and System.out.printlns. Is there any way to hide these messages for a particular object?

*EDIT: It looks like the jar file seems to be creating a bunch of threads and each thread has it's own System.out.println's...

Answer 1

Change original PrintStream with a Dummy one which does nothing on it's write() method.

Don't forget to replace original PrintStream when you finished.

System.out.println("NOW YOU CAN SEE ME");

PrintStream originalStream = System.out;

PrintStream dummyStream = new PrintStream(new OutputStream(){
    public void write(int b) {
        // NO-OP
    }
});

System.setOut(dummyStream);
System.out.println("NOW YOU CAN NOT");

System.setOut(originalStream);
System.out.println("NOW YOU CAN SEE ME AGAIN");

Answer 2

System.setOut(); is probably what you're looking for

System.setOut(new PrintStream(new OutputStream() {
  public void write(int b) {
    // NO-OP
  }
}));

Source