Java实现本地 fileCopy

前言：

　　Java中流是重要的内容，基础的文件读写与拷贝知识点是很多面试的考点。故通过本文进行简单测试总结。

2.图展示【文本IO/二进制IO】(这是参考自网上的一张总结图，相当经典，方便对比记忆)

3.文本复制的实验Java实现code:

  1 package com.gdufe.io;
  2
  3 import java.io.BufferedInputStream;
  4 import java.io.BufferedOutputStream;
  5 import java.io.DataInputStream;
  6 import java.io.DataOutputStream;
  7 import java.io.FileInputStream;
  8 import java.io.FileOutputStream;
  9 import java.io.IOException;
 10 import java.io.InputStream;
 11 import java.io.OutputStream;
 12
 13 public class TestInputOutputStream {
 14
 15 //    private final static String SOURCE="t.txt";
 16 //    private final static String TARGET="tt.txt";
 17 //    private final static String SOURCE="p.png";
 18 //    private final static String TARGET="pp.png";
 19     private final static String SOURCE="D:\\Tool_Software\\mysql-installer-community-5.6.23.0.msi";
 20     private final static String TARGET="mysql-installer-community-5.6.23.0.msi";
 21     //D:\Tool_Software\Ryuyan.zip
 22
 23
 24     public static void main(String[] args) {
 25 //        TestInputOutputStream.copy1(SOURCE, TARGET);
 26 //        TestInputOutputStream.copy2(SOURCE, TARGET);
 27         TestInputOutputStream.copy3(SOURCE, TARGET);
 28         System.out.println("--End---");
 29     }
 30
 31     public static void copy1(String src,String tar){
 32
 33         InputStream input = null;
 34         OutputStream output = null;
 35         try{
 36             input = new FileInputStream(src);
 37             output = new FileOutputStream(tar);
 38             int r;
 39             while((r=input.read())!=-1){
 40                 output.write((byte)r);
 41             }
 42         }catch(Exception e){
 43             e.printStackTrace();
 44         }finally{
 45             try {
 46                 input.close();
 47                 output.close();
 48             } catch (IOException e) {
 49                 e.printStackTrace();
 50             }
 51         }
 52
 53     }
 54     public static void copy2(String src,String tar){
 55         InputStream input = null;
 56         OutputStream output = null;
 57         try{
 58             input = new FileInputStream(src);
 59             output = new FileOutputStream(tar);
 60             int length=0;
 61             byte []b  = new byte[1024];
 62             while((length=input.read(b))!=-1){
 63                 output.write(b,0,length);
 64             }
 65         }catch(Exception e){
 66             e.printStackTrace();
 67         }finally{
 68             try {
 69                 input.close();
 70                 output.close();
 71             } catch (IOException e) {
 72                 e.printStackTrace();
 73             }
 74         }
 75     }
 76
 77     public static void copy3(String src,String tar){
 78         InputStream input = null;
 79         OutputStream output = null;
 80         try{
 81             input = new DataInputStream(new BufferedInputStream(new FileInputStream(src)));
 82             output = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(tar)));
 83             /***经过亲测，buffer缓冲流读取时确实更快一些****/
 84
 85             int length=0;
 86             byte []b  = new byte[1024];    //先将stream读入字节数组
 87             while((length=input.read(b))!=-1){
 88                 output.write(b,0,length);
 89             }
 90         }catch(Exception e){
 91             e.printStackTrace();
 92         }finally{
 93             try {
 94                 input.close();
 95                 output.close();
 96             } catch (IOException e) {
 97                 e.printStackTrace();
 98             }
 99         }
100     }
101 }

（附：参考代码时注意准备好测试文件，不然出现异常“file can‘t be found”！

　　文件拷贝到Java工程的直接目录下，刷新project可查看！

）