Java IO 之 System类

 1 package org.zln.io;
 2 
 3 import java.io.IOException;
 4 
 5 /**
 6  * Created by coolkid on 2015/6/21 0021.
 7  */
 8 public class TestSystemInReadString {
 9     public static void main(String[] args) throws IOException {
10         byte[] bytes = new byte[100];
11         int len = 0;
12         System.out.println("开始读取");
13         while ((len = System.in.read(bytes))>0){
14             System.out.println("len:"+len);
15             System.out.write(bytes, 0, len);
16             if (len>=4&&"exit".equalsIgnoreCase(new String(bytes,0,4))){
17                 break;
18             }
19         }
20         System.out.println("结束读取");
21     }
22 }

 1 package org.zln.io;
 2 
 3 /**
 4  * Created by coolkid on 2015/6/21 0021.
 5  */
 6 public class TestConsole {
 7     public static void main(String[] args) {
 8         while (true){
 9             System.out.print("开始读取:");
10             String s = System.console().readLine();
11             System.out.println("read:"+s);
12             if (s.length()>3&&"exit".equalsIgnoreCase(s.substring(0,4))){
13                 break;
14             }
15 
16         }
17         System.out.println("读取结束");
18     }
19 }

 1     private static void consoleReadPassword() {
 2         while (true){
 3             String s = new String(System.console().readPassword("%s","请输入密码："));
 4             System.out.println("read:"+s);
 5             if (s.length()>3&&"exit".equalsIgnoreCase(s.substring(0,4))){
 6                 break;
 7             }
 8 
 9         }
10         System.out.println("读取结束");
11     }