Java中常用的输入输出流

1. 抽象类InputStream\OutputStream

    方法read(), write(), close()

    流结束的判断方法 read()的返回值为-1, readLine()返回值为null

2. 文件读写类FileInputStrea\FileOutputStream

    方法: read()方法将文件读入一个byte类型的数组,其数组长度可以由in.avalialbe()方法获得

    read(byte[], int off, int len) off指从流中读入的字节所放入数组中的开始数字, len指读入长度

    write(byte[], int off, int len) off指定数组的起始位置,从该位置起的字节写入流中,len指写入长度

    byte数组的最大长度为60M,如超出则需要将文件分段

1. package example;   
2. import java.io.*;   
3.   
4. public class IOTest {   
5.   
6.     /**  
7.      * @param args  
8.      */  
9.     public static void main(String[] args) {   
10.         // TODO Auto-generated method stub   
11.         File inFile = new File("C:\\test\\1.jpg");   
12.         File outFile = new File("C:\\test\\2.jpg");   
13.            
14.         if(!outFile.exists()){   
15.             try{   
16.                 outFile.createNewFile();   
17.             }   
18.             catch(IOException ex){   
19.                 ex.printStackTrace();   
20.             }   
21.         }   
22.         try{   
23.             FileInputStream in = new FileInputStream(inFile);   
24.             byte[] array = new byte[in.available()];   
25.             in.read(array);   
26.             FileOutputStream out = new FileOutputStream(outFile);   
27.             out.write(array);   
28.             in.close();   
29.             out.close();   
30.         }   
31.         catch(FileNotFoundException ex){   
32.             ex.printStackTrace();   
33.         }   
34.         catch(IOException ex){   
35.             ex.printStackTrace();   
36.         }   
37.            
38.   
39.     }   
40.   
41. }  

package example;import java.io.*;public class IOTest {/*** @param args*/public static void main(String[] args) {// TODO Auto-generated method stubFile inFile = new File("C:\\test\\1.jpg");File outFile = new File("C:\\test\\2.jpg");if(!outFile.exists()){try{outFile.createNewFile();}catch(IOException ex){ex.printStackTrace();}}try{FileInputStream in = new FileInputStream(inFile);byte[] array = new byte[in.available()];in.read(array);FileOutputStream out = new FileOutputStream(outFile);out.write(array);in.close();out.close();}catch(FileNotFoundException ex){ex.printStackTrace();}catch(IOException ex){ex.printStackTrace();}}}

3. 管道流PipedInputStream/PiledOutputStream

    管道的建立有两种构造方式:

    1) PipedInputStream pInput = new PipedInputStream();

        PipedOutputStream pOutput = new PipedOutputStream();

    2) PipedInputStream pInput = new PipedInputStream();

        PipedOutputStream pOutput = new PipedOutputStream();

        pInput.connect(pOutput);

1. package example;   
2. import java.io.*;   
3.   
4. public class PipeTest {   
5.   
6.     /**  
7.      * @param args  
8.      */  
9.     public static void main(String[] args) {   
10.         // TODO Auto-generated method stub   
11.         PipedInputStream pipeIn = new PipedInputStream();   
12.         PipedOutputStream pipeOut = new PipedOutputStream();   
13.         try{   
14.             File f1 = new File("C:\\test\\1.txt");   
15.             File f2 = new File("C:\\test\\2.txt");   
16.             FileInputStream fileIn = new FileInputStream(f1);   
17.             pipeOut.connect(pipeIn);   
18.             Write writer = new Write(fileIn,pipeOut);   
19.             writer.start();            
20.             //byte temp[] = new byte[pipeIn.available()];   
21.             InputStreamReader inReader = new InputStreamReader(pipeIn,"GBK");   
22.             BufferedReader reader = new BufferedReader(inReader);   
23.             char temp[] = new char[10];   
24.             /* Read test 1  
25.             char temp[] = new char[20];  
26.             reader.read(temp);  
27.             String s = new String(temp);  
28.             System.out.println(temp);  
29.             */  
30.             int c= reader.read(temp);   
31.             while(c!=-1){   
32.                 System.out.println(temp);   
33.                 c= reader.read(temp);   
34.             }   
35.                
36.         }   
37.         catch(IOException ex){   
38.             ex.printStackTrace();   
39.         }   
40.   
41.     }   
42. package example;   
43. import java.io.*;   
44.   
45. public class Write extends Thread{   
46.     FileInputStream fileIn;   
47.     PipedOutputStream pipedOut;   
48.     int c =0;   
49.     public Write(FileInputStream fileIn,PipedOutputStream pipeOut){   
50.         this.fileIn = fileIn;   
51.         this.pipedOut = pipeOut;   
52.     }   
53.     public void run(){   
54.         try{   
55.             for (int i = 0; i<25; i++){   
56.                  c = fileIn.read();   
57.                  pipedOut.write(c);   
58.             }   
59.             sleep(5000);   
60.             for (int i = 0; i<10; i++){   
61.                  c = fileIn.read();   
62.                  pipedOut.write(c);   
63.             }   
64.         }   
65.         catch(IOException ex){   
66.             ex.printStackTrace();   
67.         }   
68.         catch(InterruptedException ex){   
69.             ex.printStackTrace();   
70.         }   
71.     }   
72.   
73. }   
74.     
75. }  

package example;import java.io.*;public class PipeTest {/*** @param args*/public static void main(String[] args) {// TODO Auto-generated method stubPipedInputStream pipeIn = new PipedInputStream();PipedOutputStream pipeOut = new PipedOutputStream();try{File f1 = new File("C:\\test\\1.txt");File f2 = new File("C:\\test\\2.txt");FileInputStream fileIn = new FileInputStream(f1);pipeOut.connect(pipeIn);Write writer = new Write(fileIn,pipeOut);writer.start();//byte temp[] = new byte[pipeIn.available()];InputStreamReader inReader = new InputStreamReader(pipeIn,"GBK");BufferedReader reader = new BufferedReader(inReader);char temp[] = new char[10];/* Read test 1char temp[] = new char[20];reader.read(temp);String s = new String(temp);System.out.println(temp);*/int c= reader.read(temp);while(c!=-1){System.out.println(temp);c= reader.read(temp);}}catch(IOException ex){ex.printStackTrace();}}package example;import java.io.*;public class Write extends Thread{FileInputStream fileIn;PipedOutputStream pipedOut;int c =0;public Write(FileInputStream fileIn,PipedOutputStream pipeOut){this.fileIn = fileIn;this.pipedOut = pipeOut;}public void run(){try{for (int i = 0; i<25; i++){c = fileIn.read();pipedOut.write(c);}sleep(5000);for (int i = 0; i<10; i++){c = fileIn.read();pipedOut.write(c);}}catch(IOException ex){ex.printStackTrace();}catch(InterruptedException ex){ex.printStackTrace();}}} }

   在上面的代码中,遇到的问题是,写进程sleep一段时间之后再次写入的值无法被读进程读取