大文件拷贝方法

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package top.my.test.case1;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;

public class FileCopyTest {

public static void main(String[] args) {
    // 文件大小为4.5G
    
    System.out.println(System.currentTimeMillis());
    // 1595581151315 -- 1595581253196 = 101881ms = 101s
    // copyFile(new File("D:\\xl\\big.mkv"), new File("D:\\big.mkv"));
    // 1595582378585 -- 1595582548529 = 169944ms = 169s
    // fileChannelCopy(new File("D:\\xl\\big.mkv"), new File("D:\\big2.mkv"));
    // 1595582683903 -- 1595582805496 = 121593ms = 121s
    // fileCopy(new File("D:\\xl\\big.mkv"), new File("D:\\big2.mkv"));
    // 1595583767345 -- 1595583897985 = 130640ms = 130s
    // filesCopy(new File("D:\\xl\\big.mkv"), new File("D:\\big2.mkv"));
    //1595584222455 -- 1595584325169 =  102714ms = 102s
    copyBigFile(new File("D:\\xl\\big.mkv"), new File("D:\\big.mkv"));
    System.out.println(System.currentTimeMillis());
}

// 单文件复制
public static boolean copyFile(File fromFile, File toFile) {
    try (FileInputStream in = new FileInputStream(fromFile); FileOutputStream os = new FileOutputStream(toFile);) {
        byte[] b = new byte[1024];
        int n = 0;
        while ((n = in.read(b)) != -1) {
            os.write(b, 0, n);
        }
        in.close();
        os.close();
        System.out.println("文件拷贝结束");
        return true;
    } catch (Exception e) {
        e.printStackTrace();
        return false;
    }
}

public static boolean filesCopy(File s, File t) {
    Path sourcePath = Paths.get(s.getAbsolutePath());
    Path destinationPath = Paths.get(t.getAbsolutePath());

    try {
        Files.copy(sourcePath, destinationPath, StandardCopyOption.REPLACE_EXISTING);
        return true;
    } catch (IOException e) {
        // something else went wrong
        e.printStackTrace();
    }
    return false;
}

public static boolean fileCopy(File s, File t) {
    FileInputStream fi = null;
    FileOutputStream fo = null;
    FileChannel in = null;
    FileChannel out = null;
    try {
        fi = new FileInputStream(s);
        fo = new FileOutputStream(t);
        in = fi.getChannel();// 得到对应的文件通道
        out = fo.getChannel();// 得到对应的文件通道
        long left_size = in.size();
        System.out.println("源文件大小：" + left_size / 1024 / 1024);
        long position = 0;
        while (left_size > 0) {
            long write_size = in.transferTo(position, left_size, out);
            position += write_size;
            left_size -= write_size;
        }
        // in.transferTo(0, in.size(), out);// 连接两个通道，并且从in通道读取，然后写入out通道
        System.out.println("FileChannel文件拷贝结束");
        System.out.println("目标文件大小：" + out.size() / 1024 / 1024);
        return true;
    } catch (IOException e) {
        System.out.print("文件出现拷贝异常：{}" + e.getMessage());
        ;
    } finally {
        try {
            fi.close();
            in.close();
            fo.close();
            out.close();
        } catch (IOException e) {
            System.out.print("文件出现拷贝异常：{}" + e.getMessage());
        }

    }
    return false;
}

public static boolean fileChannelCopy(File s, File t) {
    FileChannel in = null;
    FileChannel out = null;
    RandomAccessFile fi = null;
    RandomAccessFile fo = null;
    try {
        if (!t.isFile()) {
            if (!t.createNewFile()) {
                return false;
            }
        }
        fi = new RandomAccessFile(s, "r");
        fo = new RandomAccessFile(t, "rw");
        in = fi.getChannel();// 得到对应的文件通道
        out = fo.getChannel();// 得到对应的文件通道
        long left_size = in.size();
        long position = 0;
        while (left_size > 0) {
            long write_size = in.transferTo(position, left_size, out);
            position += write_size;
            left_size -= write_size;
        }
        // in.transferTo(0, in.size(), out);// 连接两个通道，并且从in通道读取，然后写入out通道
        System.out.println("FileChannel文件拷贝结束");
        return true;
    } catch (IOException e) {
        System.out.print("文件出现拷贝异常：{}" + e.getMessage());
        ;
    } finally {
        try {
            fi.close();
            in.close();
            fo.close();
            out.close();
        } catch (IOException e) {
            System.out.print("文件出现拷贝异常：{}" + e.getMessage());
        }

    }
    return false;
}

public static boolean copyBigFile(File s, File t) {
    FileInputStream fi = null;
    FileOutputStream fo = null;
    FileChannel in = null;
    FileChannel out = null;
    ByteBuffer buffer = ByteBuffer.allocate(10 * 1024);
    try {
        fi = new FileInputStream(s);
        fo = new FileOutputStream(t);
        in = fi.getChannel();// 得到对应的文件通道
        out = fo.getChannel();// 得到对应的文件通道
        while (true) {
            int read = in.read(buffer);
            if (read == -1)
                break;
            buffer.flip();
            out.write(buffer);
            buffer.clear();
        }
        System.out.println("ByteBuffer文件拷贝结束");
        return true;
    } catch (IOException e) {
        System.err.print("文件出现拷贝异常：{}" + e.getMessage());
    } finally {
        try {
            fi.close();
            in.close();
            fo.close();
            out.close();
        } catch (IOException e) {
            System.err.print("文件出现拷贝异常：{}" + e.getMessage());
        }

    }
    return false;
}

}

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