Java實現文件或文件夾的複製到指定目錄

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;

public class Test {
	private static int a = 5;

	public static void main(String[] args) {
		//需要複製的目標文件或目標文件夾
		String pathname = "C:/Users/likun/Desktop/git_project";
		File file = new File(pathname);
		//複製到的位置
		String topathname = "C:/Users/likun/Desktop/movie";
		File toFile = new File(topathname);
		try {
			copy(file, toFile);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	public static void copy(File file, File toFile) throws Exception {
		byte[] b = new byte[1024];
		int a;
		FileInputStream fis;
		FileOutputStream fos;
		if (file.isDirectory()) {
			String filepath = file.getAbsolutePath();
			filepath=filepath.replaceAll("\\\\", "/");
			String toFilepath = toFile.getAbsolutePath();
			toFilepath=toFilepath.replaceAll("\\\\", "/");
			int lastIndexOf = filepath.lastIndexOf("/");
			toFilepath = toFilepath + filepath.substring(lastIndexOf ,filepath.length());
			File copy=new File(toFilepath);
			//複製文件夾
			if (!copy.exists()) {
				copy.mkdir();
			}
			//遍歷文件夾
			for (File f : file.listFiles()) {
				copy(f, copy);
			}
		} else {
			if (toFile.isDirectory()) {
				String filepath = file.getAbsolutePath();
				filepath=filepath.replaceAll("\\\\", "/");
				String toFilepath = toFile.getAbsolutePath();
				toFilepath=toFilepath.replaceAll("\\\\", "/");
				int lastIndexOf = filepath.lastIndexOf("/");
				toFilepath = toFilepath + filepath.substring(lastIndexOf ,filepath.length());
				
				//寫文件
				File newFile = new File(toFilepath);
				fis = new FileInputStream(file);
				fos = new FileOutputStream(newFile);
				while ((a = fis.read(b)) != -1) {
					fos.write(b, 0, a);
				}
			} else {
				//寫文件
				fis = new FileInputStream(file);
				fos = new FileOutputStream(toFile);
				while ((a = fis.read(b)) != -1) {
					fos.write(b, 0, a);
				}
			}

		}
	}

}