请帮我写一个基于Java的文件管理系统

好的，下面是一个基于Java的简单文件管理系统的示例代码，包括基本的文件操作功能：

import java.io.File;
import java.io.IOException;
import java.util.Scanner;

public class FileManager {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String command;
        System.out.println("Welcome to the File Manager System.");
        while (true) {
            System.out.print("Enter a command (list, create, delete, rename, exit): ");
            command = scanner.nextLine();
            if (command.equalsIgnoreCase("list")) {
                listFiles();
            } else if (command.equalsIgnoreCase("create")) {
                createFile(scanner);
            } else if (command.equalsIgnoreCase("delete")) {
                deleteFile(scanner);
            } else if (command.equalsIgnoreCase("rename")) {
                renameFile(scanner);
            } else if (command.equalsIgnoreCase("exit")) {
                System.out.println("Exiting the program.");
                break;
            } else {
                System.out.println("Invalid command. Please enter a valid command.");
            }
        }
    }

    private static void listFiles() {
        File directory = new File(".");
        File[] files = directory.listFiles();
        for (File file : files) {
            System.out.println(file.getName());
        }
    }

    private static void createFile(Scanner scanner) {
        System.out.print("Enter the name of the file to create: ");
        String fileName = scanner.nextLine();
        File file = new File(fileName);
        try {
            if (file.createNewFile()) {
                System.out.println("File created successfully.");
            } else {
                System.out.println("File already exists.");
            }
        } catch (IOException e) {
            System.out.println("Error occurred while creating file.");
            e.printStackTrace();
        }
    }

    private static void deleteFile(Scanner scanner) {
        System.out.print("Enter the name of the file to delete: ");
        String fileName = scanner.nextLine();
        File file = new File(fileName);
        if (file.delete()) {
            System.out.println("File deleted successfully.");
        } else {
            System.out.println("Failed to delete file. File may not exist or is currently in use.");
        }
    }

    private static void renameFile(Scanner scanner) {
        System.out.print("Enter the name of the file to rename: ");
        String oldName = scanner.nextLine();
        File oldFile = new File(oldName);
        if (!oldFile.exists()) {
            System.out.println("File does not exist. Cannot rename.");
            return;
        }
        System.out.print("Enter the new name of the file: ");
        String newName = scanner.nextLine();
        File newFile = new File(newName);
        if (newFile.exists()) {
            System.out.println("File already exists. Cannot rename.");
            return;
        }
        if (oldFile.renameTo(newFile)) {
            System.out.println("File renamed successfully.");
        } else {
            System.out.println("Failed to rename file.");
        }
    }
}

这个示例程序实现了文件管理系统的基本功能，包括列出当前目录下的文件、创建文件、删除文件和重命名文件。您可以根据需要对代码进行修改和扩展。