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Java-IO流-文件复制2

package cn.bruce.IO;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class IOCopyDemo1 {
    // 文件复制方式的4种 比较
    // 1、单字节流复制
    // 2、字节数组复制
    // 3、字节流缓冲流单字节复制
    // 4、字节流缓冲区数组复制
    public static void main(String[] args) throws IOException {
        FileInputStream Zfin = new FileInputStream("E:\\a.avi");
        FileInputStream Zfin1 = new FileInputStream("E:\\a.avi");
        FileInputStream Zfin2 = new FileInputStream("E:\\a.avi");
        FileInputStream Zfin3 = new FileInputStream("E:\\a.avi");
        FileOutputStream Zfou = new FileOutputStream("E:\\dzjl.avi");// 单字节
        FileOutputStream Zfou1 = new FileOutputStream("E:\\ZJSZ.avi");// 字节数组
        FileOutputStream Zfou2 = new FileOutputStream("E:\\dzjlHC.avi");// 单字节缓冲
        FileOutputStream Zfou3 = new FileOutputStream("E:\\ZJSZHC.avi");// 字节数组缓冲
        long s = System.currentTimeMillis();
        fun1(Zfin, Zfou);// 一个一个字节的复制,太慢了
        long e = System.currentTimeMillis();
        System.out.println(e - s);
        long s1 = System.currentTimeMillis();
        fun2(Zfin1, Zfou1);// 字节数组形式的复制
        long e1 = System.currentTimeMillis();
        System.out.println(e1 - s1);
        long s2 = System.currentTimeMillis();
        fun2(Zfin2, Zfou2);// 单字节缓冲形式的复制
        long e2 = System.currentTimeMillis();
        System.out.println(e2 - s2);
        long s3 = System.currentTimeMillis();
        fun2(Zfin3, Zfou3);// 字节数组缓冲形式的复制
        long e3 = System.currentTimeMillis();
        System.out.println(e3 - s3);
    }

    // 1、单字节流复制
    public static void fun1(FileInputStream fin, FileOutputStream fou) {
        try
        {
            int len = 0;
            while ((len = fin.read()) != -1)
            {
                fou.write(len);
            }
        } catch (IOException e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                if (fou != null)
                {
                    fou.close();// 关输出流
                }
            } catch (IOException e2)
            {
                e2.printStackTrace();
                throw new RuntimeException("输出流关闭失败");
            } finally
            {
                try
                {
                    if (fin != null)
                    {
                        fin.close();// 关输入流
                    }
                } catch (IOException e2)
                {
                    e2.printStackTrace();
                    throw new RuntimeException("输入流关闭失败");
                }
            }
        }
    }

    // 2、字节数组复制
    public static void fun2(FileInputStream fin, FileOutputStream fou) {
        try
        {
            int len = 0;
            byte[] bs = new byte[1024];
            while ((len = fin.read(bs)) != -1)
            {
                fou.write(bs, 0, len);
            }
        } catch (IOException e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                if (fou != null)
                {
                    fou.close();// 关输出流
                }
            } catch (IOException e2)
            {
                e2.printStackTrace();
                throw new RuntimeException("输出流关闭失败");
            } finally
            {
                try
                {
                    if (fin != null)
                    {
                        fin.close();// 关输入流
                    }
                } catch (IOException e2)
                {
                    e2.printStackTrace();
                    throw new RuntimeException("输入流关闭失败");
                }
            }
        }
    }

    // 3、字节流缓冲流单字节复制
    public static void fun3(FileInputStream fin, FileOutputStream fou) throws IOException {
        BufferedInputStream bin = new BufferedInputStream(fin);
        BufferedOutputStream bou = new BufferedOutputStream(fou);
        try
        {
            int len = 0;
            while ((len = bin.read()) != -1)
            {
                bou.write(len);
            }
        } catch (IOException e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                if (fou != null)
                {
                    fou.close();// 关输出流
                }
            } catch (IOException e2)
            {
                e2.printStackTrace();
                throw new RuntimeException("输出流关闭失败");
            } finally
            {
                try
                {
                    if (fin != null)
                    {
                        fin.close();// 关输入流
                    }
                } catch (IOException e2)
                {
                    e2.printStackTrace();
                    throw new RuntimeException("输入流关闭失败");
                }
            }
        }
    }

    // 4、字节流缓冲区数组复制
    public static void fun4(FileInputStream fin, FileOutputStream fou) throws IOException {
        BufferedInputStream bin = new BufferedInputStream(fin);
        BufferedOutputStream bou = new BufferedOutputStream(fou);
        try
        {
            int len = 0;
            byte[] bs = new byte[1024];
            while ((len = bin.read(bs)) != -1)
            {
                bou.write(bs, 0, len);
            }
        } catch (IOException e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                if (fou != null)
                {
                    fou.close();// 关输出流
                }
            } catch (IOException e2)
            {
                e2.printStackTrace();
                throw new RuntimeException("输出流关闭失败");
            } finally
            {
                try
                {
                    if (fin != null)
                    {
                        fin.close();// 关输入流
                    }
                } catch (IOException e2)
                {
                    e2.printStackTrace();
                    throw new RuntimeException("输入流关闭失败");
                }
            }
        }
    }
}

 

posted @ 2020-08-24 10:14  萧静默  阅读(114)  评论(0编辑  收藏  举报