在Java中将文件从一个目录复制到另一个目录

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class CopyFiles {
    private File targetFolder;
    private int noOfFiles;
    public void copyDirectory(File sourceLocation, String destLocation)
            throws IOException {
        targetFolder = new File(destLocation);
        if (sourceLocation.isDirectory()) {
            if (!targetFolder.exists()) {
                targetFolder.mkdir();
            }

            String[] children = sourceLocation.list();
            for (int i = 0; i < children.length; i++) {
                copyDirectory(new File(sourceLocation, children[i]),
                        destLocation);

            }
        } else {

            InputStream in = new FileInputStream(sourceLocation);
            OutputStream out = new FileOutputStream(targetFolder + "\\"+ sourceLocation.getName(), true);
            System.out.println("Destination Path ::"+targetFolder + "\\"+ sourceLocation.getName());            
            // Copy the bits from instream to outstream
            byte[] buf = new byte[1024];
            int len;
            while ((len = in.read(buf)) > 0) {
                out.write(buf, 0, len);
            }
            in.close();
            out.close();
            noOfFiles++;
        }
    }

    public static void main(String[] args) throws IOException {

        File srcFolder = new File("C:\\sourceLocation\\");
        String destFolder = new String("C:\\targetLocation\\");
        CopyFiles cf = new CopyFiles();
        cf.copyDirectory(srcFolder, destFolder);
        System.out.println("No Of Files got Retrieved from Source ::"+cf.noOfFiles);
        System.out.println("Successfully Retrieved");
    }
}

如果您不想使用外部库，而是想使用java.io而不是java.nio类，您可以使用这种简洁的方法来复制文件夹及其所有内容：

/**
 * Copies a folder and all its content to another folder. Do not include file separator at the end path of the folder destination.
 * @param folderToCopy The folder and it's content that will be copied
 * @param folderDestination The folder destination
 */
public static void copyFolder(File folderToCopy, File folderDestination) {
    if(!folderDestination.isDirectory() || !folderToCopy.isDirectory())
        throw new IllegalArgumentException("The folderToCopy and folderDestination must be directories");

    folderDestination.mkdirs();

    for(File fileToCopy : folderToCopy.listFiles()) {
        File copiedFile = new File(folderDestination + File.separator + fileToCopy.getName());

        try (FileInputStream fis = new FileInputStream(fileToCopy);
             FileOutputStream fos = new FileOutputStream(copiedFile)) {

            int read;
            byte[] buffer = new byte[512];

            while ((read = fis.read(buffer)) != -1) {
                fos.write(buffer, 0, read);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }


    }
}

我提供了一种替代方案，无需使用第三方工具，如apache FileUtils。这可以通过命令行完成。

我在Windows上测试过，对我有效。下面是Linux的解决方案。

在这里，我利用Windows xcopy 命令来复制包括子目录在内的所有文件。我传递的参数如下所定义。

• /e - 复制所有子目录，即使它们为空。
• /i - 如果源是目录或包含通配符，并且目标不存在，则 xcopy 假定目标指定一个目录名称并创建一个新目录。然后，xcopy 将所有指定的文件复制到新目录中。
• /h - 复制带有隐藏和系统文件属性的文件。默认情况下，xcopy 不会复制隐藏或系统文件

我的示例利用 ProcessBuilder 类构建进程来执行复制（xcopy & cp）命令。

Windows：

String src = "C:\\srcDir";
String dest = "C:\\destDir";
List<String> cmd = Arrays.asList("xcopy", src, dest, "/e", "/i", "/h");
try {
    Process proc = new ProcessBuilder(cmd).start();
    BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
    String line = null;
    while ((line = inp.readLine()) != null) {
        System.out.println(line);
    }
} catch (IOException e) {
    e.printStackTrace();
}

Linux：

String src = "srcDir/";
String dest = "~/destDir/";
List<String> cmd = Arrays.asList("/bin/bash", "-c", "cp", "r", src, dest);
try {
    Process proc = new ProcessBuilder(cmd).start();
    BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
    String line = null;
    while ((line = inp.readLine()) != null) {
        System.out.println(line);
    }
} catch (IOException e) {
    e.printStackTrace();
}

或者是一个可以在Windows或Linux环境下工作的组合。

private static final String OS = System.getProperty("os.name");
private static String src = null;
private static String dest = null;
private static List<String> cmd = null;

public static void main(String[] args) {
    if (OS.toLowerCase().contains("windows")) { // setup WINDOWS environment
        src = "C:\\srcDir";
        dest = "C:\\destDir";
        cmd = Arrays.asList("xcopy", src, dest, "/e", "/i", "/h");

        System.out.println("on: " + OS);
    } else if (OS.toLowerCase().contains("linux")){ // setup LINUX environment
        src = "srcDir/";
        dest = "~/destDir/";
        cmd = Arrays.asList("/bin/bash", "-c", "cp", "r", src, dest);

        System.out.println("on: " + OS);
    }

    try {
        Process proc = new ProcessBuilder(cmd).start();
        BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
        String line = null;
        while ((line = inp.readLine()) != null) {
            System.out.println(line);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

}

你需要使用renameTo() - 这不是很明显，我知道...但它是Java中move的等效操作...