import java.io.*;
import java.util.*;
import javax.swing.*;
import javax.swing.text.*;

import org.pd.zj.util.LoopedStreams;

public class ConsoleTextArea extends JTextArea {
 public ConsoleTextArea(InputStream[] inStreams) {
  for (int i = 0; i < inStreams.length; ++i)
   startConsoleReaderThread(inStreams[i]);
 } // ConsoleTextArea()

 public ConsoleTextArea() throws IOException {
  final LoopedStreams ls = new LoopedStreams();
  // 重定向System.out和System.err
  PrintStream ps = new PrintStream(ls.getOutputStream());
  System.setOut(ps);
  System.setErr(ps);
  startConsoleReaderThread(ls.getInputStream());
 } // ConsoleTextArea()

 private void startConsoleReaderThread(InputStream inStream) {
  final BufferedReader br = new BufferedReader(new InputStreamReader(inStream));
  new Thread(new Runnable() {
   public void run() {
    StringBuffer sb = new StringBuffer();
    try {
     String s;
     Document doc = getDocument();
     while ((s = br.readLine()) != null) {
      boolean caretAtEnd = false;
      caretAtEnd = getCaretPosition() == doc.getLength() ? true : false;
      sb.setLength(0);
      append(sb.append(s).append('\n').toString());
      if (caretAtEnd)
       setCaretPosition(doc.getLength());
     }
    } catch (IOException e) {
     JOptionPane.showMessageDialog(null, "从BufferedReader读取错误：" + e);
     System.exit(1);
    }
   }
  }).start();
 } // startConsoleReaderThread()

 // 该类剩余部分的功能是进行测试
 public static void main(String[] args) {
  JFrame f = new JFrame("ConsoleTextArea测试");
  ConsoleTextArea consoleTextArea = null;
  try {
   consoleTextArea = new ConsoleTextArea();
  } catch (IOException e) {
   System.err.println("不能创建LoopedStreams：" + e);
   System.exit(1);
  }
  consoleTextArea.setFont(java.awt.Font.decode("monospaced"));
  f.getContentPane().add(new JScrollPane(consoleTextArea), java.awt.BorderLayout.CENTER);
  f.setBounds(50, 50, 500, 500);
  f.setVisible(true);
  f.addWindowListener(new java.awt.event.WindowAdapter() {
   public void windowClosing(java.awt.event.WindowEvent evt) {
    System.exit(0);
   }
  });
  
  // 启动几个写操作线程向
  // System.out和System.err输出
  startWriterTestThread("写操作线程 #1", System.err, 920, 50);
  startWriterTestThread("写操作线程 #2", System.out, 500, 50);
  startWriterTestThread("写操作线程 #3", System.out, 200, 50);
  startWriterTestThread("写操作线程 #4", System.out, 1000, 50);
  startWriterTestThread("写操作线程 #5", System.err, 850, 50);
 }

 private static void startWriterTestThread(final String name, final PrintStream ps, final int delay, final int count) {
  new Thread(new Runnable() {
   public void run() {
    for (int i = 1; i <= count; ++i) {
     ps.println("***" + name + ", hello !, i=" + i);
     try {
      Thread.sleep(delay);
     } catch (InterruptedException e) {
     }
    }
   }
  }).start();
 }
}

注意：想要输出log信息，必须在输出到控制台的配置加上log4j.appender.XXX.follow = true,并且日志jar包为log4j-1.2.13.jar以上版本。