System.out.println 输出信息到文件

File file=new File("e:/log.txt");
FileOutputStream fos=new FileOutputStream(file,true);//true:append
BufferedOutputStream bos=new BufferedOutputStream(fos);
PrintStream ps=new PrintStream(bos,true);//true:auto flush
System.setOut(ps);
System.out.println("将信息输入到文件，而不是控制台");

//System.setOut(new PrintStream(new BufferedOutputStream(new FileOutputStream(new File("e:/log.txt"),true)),true));
System.setOut(new PrintStream(new BufferedOutputStream(new FileOutputStream("e:/log.txt",true)),true));//输出到文件

System.setOut(new PrintStream(new BufferedOutputStream(new FileOutputStream(FileDescriptor.out)),true));//重新输入到控制台