recursion - Java 8 : Copy directory recursively?

Question

我发现 Java 8 已经显着清理了将文件内容读取到字符串中的过程:

String contents = new String(Files.readAllBytes(Paths.get(new URI(someUrl))));

我想知道是否有类似的东西(更干净/更少的代码/更简洁)用于递归复制目录。在 Java 7 领域，它仍然是这样的:

public void copyFolder(File src, File dest) throws IOException{
    if(src.isDirectory()){
        if(!dest.exists()){
            dest.mkdir();
        }

        String files[] = src.list();

        for (String file : files) {
            File srcFile = new File(src, file);
            File destFile = new File(dest, file);

            copyFolder(srcFile,destFile);
        }

    } else {
        InputStream in = new FileInputStream(src);
        OutputStream out = new FileOutputStream(dest); 

        byte[] buffer = new byte[1024];

        int length;
        while ((length = in.read(buffer)) > 0){
            out.write(buffer, 0, length);
        }

        in.close();
        out.close();
    }
}

Java 8 有什么改进吗？

Answer 1

这样代码看起来简单了一些

import static java.nio.file.StandardCopyOption.*;

public  void copyFolder(Path src, Path dest) throws IOException {
    try (Stream<Path> stream = Files.walk(src)) {
        stream.forEach(source -> copy(source, dest.resolve(src.relativize(source))));
    }
}

private void copy(Path source, Path dest) {
    try {
        Files.copy(source, dest, REPLACE_EXISTING);
    } catch (Exception e) {
        throw new RuntimeException(e.getMessage(), e);
    }
}