mail-2001-03-13t0646

来自「实现在电脑平台上控制短信modem或手机进行通讯的jar包和相关实例」· 代码 · 共 60 行

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RE: diverting System.stderr/stdout into log4j
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From: Michael Smith 
Subject: RE: diverting System.stderr/stdout into log4j 
Date: Tue, 13 Mar 2001 06:46:04 -0800 

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There is another way!

In LogLog, completely ignore System.err.  Instead, use the following to get
the standard error stream:

PrintStream err =
  new PrintStream(new FileOutputStream(FileDescriptor.err));

When you use System.setErr, it changes System.err, but not
FileDescriptor.err, which maintains a descriptor for the original error
stream.

michael

For a sample program to test this, see below:

import java.io.*;

public class Stderr {

  public static void main(String[] args) {

    // create a print stream to represent a redirect
    PrintStream nonStandardErr = 
      new PrintStream(new ByteArrayOutputStream());
    
    // Redirect standard out and standard err
    System.setOut(nonStandardErr);
    System.setErr(nonStandardErr);
    
    // attempt to print something
    System.err.println("You should *not* see this on the console!");
	
    // the stuff that would appear in LogLog
    PrintStream logLogOut = 
      new PrintStream(new FileOutputStream(FileDescriptor.err));
    
    // attempt to print something
    logLogOut.println("You *should* see this on the console!");
  }
}



> -----Original Message-----
> From: Ceki G黮c