I want to recursively create a copy of a directory and all its contents (e.g. files and subdirectories).

To recursively create a copy of a directory and all its contents in Java, you can use the Java NIO (New I/O) package, specifically the Files and Paths classes. Here's an example of how you can achieve this:

java

import java.io.IOException;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;

public class DirectoryCopyExample {
    public static void main(String[] args) throws IOException {
        Path sourceDir = Paths.get("source-directory");
        Path targetDir = Paths.get("target-directory");

        copyDirectory(sourceDir, targetDir);
    }

    public static void copyDirectory(Path sourceDir, Path targetDir) throws IOException {
        Files.walkFileTree(sourceDir, new SimpleFileVisitor<Path>() {
            @Override
            public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
                Path targetDirPath = targetDir.resolve(sourceDir.relativize(dir));
                Files.createDirectories(targetDirPath);
                return FileVisitResult.CONTINUE;
            }

            @Override
            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                Path targetFilePath = targetDir.resolve(sourceDir.relativize(file));
                Files.copy(file, targetFilePath, StandardCopyOption.REPLACE_EXISTING);
                return FileVisitResult.CONTINUE;
            }
        });
    }
}

In this example:

    sourceDir is the directory you want to copy.
    targetDir is the destination directory where the copy will be created.

The copyDirectory method uses the Files.walkFileTree method to traverse the source directory's contents recursively. For each directory visited, it creates a corresponding directory in the target directory. For each file visited, it copies the file to the target directory.

Remember to replace "source-directory" and "target-directory" with the actual paths you want to use.

Note that this code uses Java NIO and requires Java 7 or later. It's recommended to handle exceptions properly in a real-world scenario.