JavaSE练习--IO_两首音乐串烧

完成效果：

将a.mp3和b.mp3分别等分截取成两段partA1、partA2、partB1、partB2，

然后将partA1和partB1、partA2、partB2组合成c.mp3

思路：

获取字节文件长度，然后分成两段

选用字节缓冲流，实现读写

 1 package com.heqing.test;
 2 
 3 import java.io.*;
 4 
 5 public class Test3 {
 6     public static void main(String[] args) {
 7         File fileA = new File("m2/a.mp3");
 8         File fileB = new File("m2/b.mp3");
 9         long lengthA,partA1,partA2,lengthB,partB1,partB2;
10         lengthA = fileA.length();
11         partA1 = lengthA /2;
12         partA2 = lengthA /2 + lengthA %2;
13         lengthB = fileB.length();
14         partB1 = lengthB /2;
15         partB2 = lengthB /2 + lengthB %2;
16         try(BufferedInputStream fisa = new BufferedInputStream(new FileInputStream(fileA));
17             BufferedInputStream fisb = new BufferedInputStream(new FileInputStream(fileB));
18             BufferedOutputStream fos = new BufferedOutputStream(new FileOutputStream("m2/c.mp3"))){
19             for (int i = 0; i < partA1; i++) {
20                 fos.write(fisa.read());
21             }
22             for (int i = 0; i < partB1; i++) {
23                 fos.write(fisb.read());
24             }
25             for (int i = 0; i < partA2; i++) {
26                 fos.write(fisa.read());
27             }
28             for (int i = 0; i < partB2; i++) {
29                 fos.write(fisb.read());
30             }
31             fos.flush();
32         } catch (FileNotFoundException e) {
33             e.printStackTrace();
34         } catch (IOException e) {
35             e.printStackTrace();
36         }
37     }
38 }