文件的改名和复制，删除

文件改名

一个：
public class YanShiDeno {
public static void main(String[] args) {
File file = new File(“C:\Users\Administrator\Desktop\wsds2d\aaa1.png”);
file.renameTo(new File(file.getParentFile()+"\"+“bbb.jpg”));//改变了源文件路径，并重命名或者不改变源文件路径只重命名

}

}
一级目录下多个文件改名
package ykofdjijide;

import java.io.File;
import java.util.Random;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) {
  File file = new File(“C:\Users\Administrator\Desktop\wsds2d”);
  File[] files = file.listFiles();//罗列出此目录下的所有文件
  for (File file1 : files) { //遍历这个目录下的文件
  file1.renameTo(new File(file1.getParentFile(),“bbbb”+(new Random().nextInt(10)) + “.png”));
  }

  }
  }
  多级选择性改名：
  package ykofdjijide;

import eydgyyge.Gaiming;

import java.io.File;
import java.util.Random;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) {
  File file = new File(“C:\Users\Administrator\Desktop\wsds2d”);
  gaiming(file);

  }

  private static void gaiming(File file) {
  File[] files = file.listFiles();
  for (File file1 : files) {
  if (file1.isFile()&&file1.getName().endsWith(".jpg")){//是文件而且文件名中含有".jpg"
  file1.renameTo(new File(file1.getParentFile()+"\"+“aaaa”+(new Random().nextInt(10))+“png”));
  }else if(!file1.isFile()){//文件夹
  gaiming(file1);//递归再次罗列此文件夹
  }
  }
  }
  }
  多级选择删除
  package ykofdjijide;

import java.io.File;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) {
  File file = new File(“C:\Users\Administrator\Desktop\wsds2d”);
  gaiming(file);

  }

  private static void gaiming(File file) {
  File[] files = file.listFiles();
  for (File file1 : files) {
  if (file1.isFile()&&file1.getName().endsWith(“png”)){//是文件而且文件名中含有".jpg"
  file1.delete(); //删除文件
  }else if(!file1.isFile()){//文件夹
  gaiming(file1);//递归再次罗列此文件夹
  }
  }
  }
  }

Io流.复制

复制一个文件：
package ykofdjijide;

import java.io.*;

/**

• @Author: Administrator
• @CreateTime: 2019-01-17 14:35
  /
  public class YanShiDeno {
  public static void main(String[] args) throws IOException {
  FileInputStream in = new FileInputStream(“C:\Users\Administrator\Desktop\wsds2d - 副本\月半小夜曲 (Live)-中国好声音.mp3”);
  FileOutputStream out = new FileOutputStream(new File(“D:\月半小夜曲 (Live)-中国好声音.mp3”));
  byte[] bytes = new byte[10248];//缓存区
  int num=0;
  while ((num=in.read(bytes))!=-1){
  out.write(bytes,0,num);
  out.flush();
  }
  in.close();
  out.close();
  }
  }
  复制一级目录文件
  package ykofdjijide;

import java.io.*;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) throws IOException {
  File jiu = new File(“C:\Users\Administrator\Desktop\wsds2d”);
  File xin = new File(“D:\wsds2d”);
  if(!xin.exists()){//判断有没有目标文件夹
  xin.mkdirs();//没有则新建
  }
  bianli(jiu, xin);
  }

  private static void bianli(File jiu, File xin) throws IOException {
  File[] files = jiu.listFiles();
  for (File file : files) {
  fuzhi(file, xin);
  }
  }

  private static void fuzhi(File file, File xin) throws IOException {
  FileInputStream in = new FileInputStream(file);
  FileOutputStream out = new FileOutputStream(new File(xin, file.getName()));
  byte[] bytes = new byte[1024 * 8];
  int num=0;
  while ((num=in.read(bytes))!=-1){
  out.write(bytes,0,num);
  out.flush();
  }
  in.close();
  out.close();
  }
  }
  复制多级文件夹
  package ykofdjijide;

import java.io.*;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) throws IOException {
  File jiu = new File(“C:\Users\Public\Desktop\激活.驱动”);
  File xin = new File(“D:\激活.驱动”);
  if(!xin.exists()){//判断有没有目标文件夹
  xin.mkdirs();//没有则新建
  }
  bianli(jiu, xin);
  }

  private static void bianli(File jiu, File xin) throws IOException {
  File[] files = jiu.listFiles();
  for (File file : files) {
  if (file.isFile()){
  fuzhi(file, xin);
  }
  else {
  File file1 = new File(xin,file.getName());
  if (!file1.exists()) {//判断有没有目标文件夹
  file1.mkdirs();//没有则新建
  }
  bianli(file,file1);
  }
  }
  }

  private static void fuzhi(File file, File xin) throws IOException {
  FileInputStream in = new FileInputStream(file);
  FileOutputStream out = new FileOutputStream(new File(xin, file.getName()));
  byte[] bytes = new byte[1024 * 8];
  int num=0;
  while ((num=in.read(bytes))!=-1){
  out.write(bytes,0,num);
  out.flush();
  }
  in.close();
  out.close();
  }
  }
  复制过程中选择性改名
  package ykofdjijide;

import java.io.*;

/**

• @Author: Administrator

• @CreateTime: 2019-01-17 14:35
  */
  public class YanShiDeno {
  public static void main(String[] args) throws IOException {
  File jiu = new File(“C:\Users\Administrator\Desktop\wsds2d - 副本”);
  File xin = new File(“D:\wsds2d - 副本”);
  if(!xin.exists()){//判断有没有目标文件夹
  xin.mkdirs();//没有则新建
  }
  bianli(jiu, xin);
  }

  private static void bianli(File jiu, File xin) throws IOException {
  File[] files = jiu.listFiles();
  for (File file : files) {
  if (file.isFile()){
  fuzhi(file, xin);
  }
  else {
  File file1 = new File(xin,file.getName());
  if (!file1.exists()) {//判断有没有目标文件夹
  file1.mkdirs();//没有则新建
  }
  bianli(file,file1);
  }
  }
  }

  private static void fuzhi(File file, File xin) throws IOException {
  FileInputStream in = new FileInputStream(file);
  File file1 = new File(xin, file.getName());
  FileOutputStream out = new FileOutputStream(file1);
  byte[] bytes = new byte[1024 * 8];
  int num=0;
  while ((num=in.read(bytes))!=-1){
  out.write(bytes,0,num);
  out.flush();
  }
  in.close();
  out.close();
  faiming(file1);//抽取一个改名方法
  }

  private static void faiming(File file1) {
  if(file1.getName().endsWith(".jpg")){
  file1.renameTo(new File(file1.getParentFile()+"\"+file1.getName().replace(".jpg",".png")));
  }
  }
  }
  集合中的文本文件复制到txt文件中
  package gdeyuuw;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Comparator;
import java.util.Scanner;
import java.util.TreeSet;

/**

• @Author: Administrator

• @CreateTime: 2019-01-16 12:48
  */
  public class FuZhi {
  public static void main(String[] args) throws IOException {
  TreeSet jihe = new TreeSet<>(new Comparator() {
  @Override
  public int compare(Student s1, Student s2) {
  int num=s1.zongFen()-s2.zongFen();
  int num2=num==0?s1.getName().compareTo(s2.getName()):num;
  return num2;
  }
  });
  for (int i = 0; i < 3; i++) {

       Scanner sc = new Scanner(System.in);
       System.out.println("请输入姓名");
       String s = sc.nextLine();
       System.out.println("请输入数学成绩");
       Integer shux = new Integer(sc.nextLine());
       System.out.println("请输入语文成绩");
       Integer yuwen = new Integer(sc.nextLine());
       System.out.println("请输入英语成绩");
       Integer yingyu = new Integer(sc.nextLine());
       jihe.add(new Student(s,yuwen,shux,yingyu));
   }
   BufferedWriter out = new BufferedWriter(new FileWriter("a.txt"));
   out.write("姓名\t"+"语文成绩\t"+"数学\t"+"英语\t"+"总分");
   out.flush();
   out.newLine();
   for (Student student : jihe) {
       out.write(student.getName()+"\t"+student.getYuwen()+"\t"+student.getShux()+"\t"+student.getYingyu()+"\t"+student.zongFen());
       out.flush();
       out.newLine();
  
   }
   out.close();
  

  }

}