PrintWriter和PrintStream都属于输出流，分别针对字符和字节。

　　PrintWriter和PrintStream提供了重载的print,println方法用于多种类型的输出

　　PrintWriter和PrintStream的输出操作不会抛出异常，用户通过检测错误状态获取错误信息。

 

 1 import java.io.File;
 2 import java.io.FileNotFoundException;
 3 import java.io.FileOutputStream;
 4 import java.io.PrintStream;
 5 
 6 
 7 public class TestPrintStream1 {
 8 
 9     /**
10      * @param args
11      */
12     public static void main(String[] args) {
13         // TODO Auto-generated method stub
14         PrintStream ps=null;
15         try {
16             FileOutputStream fos=new FileOutputStream("d:"+File.separator+"test.txt");
17             ps=new PrintStream(fos);
18         } catch (FileNotFoundException e) {
19             e.printStackTrace();
20         }
21         if(ps!=null){
22             System.setOut(ps);
23         }
24         
25         int l=0;
26         for(char c=0;c<=60000;c++){
27             System.out.println(c);
28         }
29     }
30 
31 }

 

 1 import java.io.*;
 2 public class TestPrintStream2 {
 3   public static void main(String[] args) {
 4     String filename = args[0];
 5     if(filename!=null){list(filename,System.out);}
 6   }
 7   public static void list(String f,PrintStream fs){
 8     try {
 9       BufferedReader br = 
10                   new BufferedReader(new FileReader(f));
11       String s = null; 
12       while((s=br.readLine())!=null){
13         fs.println(s);            
14       }
15       br.close();
16     } catch (IOException e) {
17       fs.println("无法读取文件");
18     }
19   }
20 }

 

 1 import java.util.*; 
 2 import java.io.*;
 3 public class TestPrintStream3 {
 4   public static void main(String[] args) {
 5     String s = null;
 6     BufferedReader br = new BufferedReader(
 7                         new InputStreamReader(System.in));
 8     try {
 9       FileWriter fw = new FileWriter
10                            ("d:\\bak\\logfile.log", true); 
11       PrintWriter log = new PrintWriter(fw);
12       while ((s = br.readLine())!=null) {
13         if(s.equalsIgnoreCase("exit")) break;
14         System.out.println(s.toUpperCase());
15         log.println("-----");
16         log.println(s.toUpperCase()); 
17         log.flush();
18       }
19       log.println("==="+new Date()+"==="); 
20       log.flush();
21       log.close();
22     } catch (IOException e) {
23       e.printStackTrace();
24     }
25   }
26 }