1 package demo05; 2  3 import java.io.BufferedReader; 4 import java.io.File; 5 import java.io.FileNotFoundException; 6 import java.io.FileOutputStream; 7 import java.io.FileReader; 8 import java.io.FileWriter; 9 import java.io.IOException;10 import java.io.PrintWriter;11 12 public class PrintWriterDemo {13     public static void main(String[] args) throws IOException {14          File file = new File("c:\\1.txt");15          PrintWriter pw = new PrintWriter(file);16          //原样输出17          pw.println(100);18          pw.flush();19          pw.close();20          21          FileOutputStream fos = new FileOutputStream("c:\\2.txt");22          PrintWriter pw1 = new PrintWriter(fos, true); //自动刷新23          pw1.println("java");24          pw1.close();25          26          //文件复制27          BufferedReader bfr = new BufferedReader(new FileReader("c:\\3.txt"));28          PrintWriter pw11 = new PrintWriter(new FileWriter("d:\\3.txt"));29          String line = null;30          while ((line = bfr.readLine()) != null) {31              pw11.println(line);32          }33          pw11.close();34          bfr.close();35     }36     37     38 }