Java in the folder to another folder

1. Copy the folder ***

public static void copyDir(String sourcePath, String newPath) {
        File start = new File(sourcePath);
        File end = new File(newPath);
        String[] filePath = start.list();       //获取该文件夹下的所有文件以及目录的名字
        if(!end.exists()) {
            end.mkdir();
        }
        for(String temp:filePath) {
            //查看其数组中每一个是文件还是文件夹
            if(new File(sourcePath+File.separator+temp).isDirectory()) {
                //为文件夹，进行递归
                copyDir(sourcePath+File.separator+temp, newPath+File.separator+temp);
            }else {
                //为文件则进行拷贝
                copyFile(sourcePath+File.separator+temp, newPath+File.separator+temp);
            }
        }
    }

2. copy the file

public static void copyFile(String sourcePath, String newPath) {
        File start = new File(sourcePath);
        File end = new File(newPath);
        try(BufferedInputStream bis=new BufferedInputStream(new FileInputStream(start));
            BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(end))) {
            int len = 0;
            byte[] flush = new byte[1024];
            while((len=bis.read(flush)) != -1) {
                bos.write(flush, 0, len);
            }
            bos.flush();
        }catch(FileNotFoundException e) {
            e.printStackTrace();
        }catch(IOException e) {
            e.printStackTrace();
        }
    }

Note: In this function, is used to enhance java7 try statement to close the resource. It allows keeping a pair of parentheses after the try keyword, which can declare, initialize one or more resources (separated by semicolons between different resources), the resource here refers to those procedures must end display off resources (database connections, network connections, etc.), try these resources statement automatically shut down at the end of the statement.

3. calling function

public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("From：");
        String sourcePath = scanner.nextLine();
        System.out.print("To：");
        String newPath = scanner.nextLine();
        copyDir(sourcePath, newPath);
    }

4. Source Code

/**
 * 
 * 复制文件夹d:/java下面所有文件和子文件夹内容到d:/java2。
    提示：涉及单个文件复制、目录的创建、递归的使用
 */
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Scanner;

public class Practice01{
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("From：");
        String sourcePath = scanner.nextLine();
        System.out.print("To：");
        String newPath = scanner.nextLine();
        copyDir(sourcePath, newPath);
    }
    
    //文件夹的拷贝
    public static void copyDir(String sourcePath, String newPath) {
        File start = new File(sourcePath);
        File end = new File(newPath);
        String[] filePath = start.list();       //获取该文件夹下的所有文件以及目录的名字
        if(!end.exists()) {
            end.mkdir();
        }
        for(String temp:filePath) {
            //查看其数组中每一个是文件还是文件夹
            if(new File(sourcePath+File.separator+temp).isDirectory()) {
                //为文件夹，进行递归
                copyDir(sourcePath+File.separator+temp, newPath+File.separator+temp);
            }else {
                //为文件则进行拷贝
                copyFile(sourcePath+File.separator+temp, newPath+File.separator+temp);
            }
        }
    }
    
    //文件的拷贝
    public static void copyFile(String sourcePath, String newPath) {
        File start = new File(sourcePath);
        File end = new File(newPath);
        try(BufferedInputStream bis=new BufferedInputStream(new FileInputStream(start));
            BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(end))) {
            int len = 0;
            byte[] flush = new byte[1024];
            while((len=bis.read(flush)) != -1) {
                bos.write(flush, 0, len);
            }
            bos.flush();
        }catch(FileNotFoundException e) {
            e.printStackTrace();
        }catch(IOException e) {
            e.printStackTrace();
        }
    }
}

Of course, and more operations related files and streams, may be used jar packets related to the Apache Software Foundation (commons-io).

PS: Commons-IO Download