java基础☕️(5)

/**
 * FileName: EnumTest
 * Author:   ooowl
 * Date:     12/30/2019 9:21 PM
 * Description: 测试enum
 */

public class EnumTest
{
    public static void main(String args[]) {
        Seasons spring1=Seasons.SPRING;//获取一个Season的对象
        spring1.showInfo();
        Seasons spring2=Seasons.SPRING;//获取一个Season的对象
        System.out.println(spring1.equals(spring2));
    }
}
enum Seasons{
    //声明枚举实例
    SPRING("春天","春暖花开"),//相当调用了私有构造方法,在静态区申请了单例
    SUMMER("夏天","夏日炎炎"),
    AUTUMN("秋天","秋高气爽"),
    WINTER("冬天","凌冽寒冬");
    
    //声明枚举类的属性
    private final String name;
    private final String desc;

    //构造函数
    private Seasons(String name, String desc){
        this.desc=desc;
        this.name=name;
    }
    
    // 其他方法
    public void showInfo(){
        System.out.println(this.name+":"+this.desc);
    }

}

package javaioPractice;

import javax.swing.*;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Field;

public class FileP {
    public static void main(String args[]) {
        System.out.println("hello world");
        File f1 = new File("D:"+File.separator+"Test\\sad.txt");
        //访问文件名
        System.out.println(f1.getName());
        File f2=new File("src/javaioPractice/xxx");
        System.out.println("f2.exists()"+f2.exists());
        System.out.println("f2.getPath()"+f2.getPath());
        System.out.println("f2.getAbsolutePath()"+f2.getAbsolutePath());
        System.out.println("f2"+f2);
        System.out.println("f2.getAbsoluteFile()"+f2.getAbsoluteFile());
        System.out.println("f1.getParent()"+f1.getParent());
        f2.renameTo(new File("D:/Test/xxx"));
        File f3=new File("D:/Test/xxx");
        System.out.println("f3.exists()"+f3.exists());
        System.out.println("f3.canExecute()"+f3.canExecute());
        System.out.println("f3.canRead()"+f3.canRead());
        System.out.println("f3.canWrite()"+f3.canWrite());
        System.out.println("f3.isFile()"+f3.isFile());
        System.out.println("f3.isDirectory()"+f3.isDirectory());
        System.out.println("f3.lastModified()"+f3.lastModified());
        System.out.println("f3.length()"+f3.length());
        File f4= new File("D:/Test/x3.txt");
        if(!f4.exists()){
            try{
                f4.createNewFile();
            }catch (IOException e){
                e.printStackTrace();
                System.out.println(e.getMessage());
            }
        }
        f2.delete();
        File f5=new File("D:/Test/aa/bb") ;
        f5.mkdir();
        File f6=new File("D:/Test");
        String fl[]=f6.list();//注意返回的是String,包括目录和文件
        for (String s:fl) {
            System.out.println(s);
        }
        File[] fs=f6.listFiles();//这次返回的是File对象
        for (File f  : fs) {
            System.out.println(f);
        }
        Traversal t= new Traversal();
        try{
            t.Travers(new File("D:/Test"));
        }catch (IOException e){
            e.printStackTrace();
        }

    }
}

class Traversal{//递归遍历文件夹
    public void Travers(File f) throws Exception {
        if (!f.exists()){
            Exception e=new IOException();
            throw e;
        }
        if (f.isFile()){
            System.out.println(f);
        }else if(f.isDirectory()){
            for (File f1  :f.listFiles() ) {
                System.out.println(f);
                Travers(f1);
            }
        };
    }
}

package javaioPractice;

import java.io.*;

public class FileIO {
    public static void main(String args[]) {
        System.out.println("hello world");
        IOclass t=new IOclass();
//        t.inS("D:\\Test\\sad.txt");
//        t.outS("D:\\Test\\sad1.txt");
        t.cpf("D:\\Test\\sad.txt","D:\\Test\\sadx.txt");

    }
}
class IOclass{
    public void inS(String Dir){
        try{
            FileInputStream in=new FileInputStream(Dir);
            //BufferedInputStream br=new BufferedInputStream(in);
            byte b[]=new byte[10];
            int len =0;//为啥是0
            //in.read(b);
            while((len=in.read(b))!=-1){//while((len=br.read(b))!=-1)//使用缓冲字节流
                System.out.print(new String(b,0,len));
                //参数1是缓冲数据的数组，参数2是从数组的哪个位置开始转化字符串，参数3是总共转化几个字节
            }
            //br.close();//使用缓冲字节流
            in.close();
        }catch (IOException e){
            e.printStackTrace();
        }finally {
            System.out.println("");
            System.out.println("输出完毕!--------------------------");
        }
    }
    public void outS(String Dir){
        try {
            FileOutputStream os=new FileOutputStream(Dir);
            //BufferedOutputStream bo=new BufferedOutputStream(os);
            String s="sdsadvsjdksa";//申请字符串
            os.write(s.getBytes());//把字符串转化为byte,写到内存,然后写入文件
            //bo.write(s.getBytes());//把字符串转化为byte,写到内存,然后写入内存
            //bo.flush();//刷到硬盘
            //bo.close();
            os.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public void cpf(String src,String dst){

        try {
            FileInputStream in=new FileInputStream(src);
            FileOutputStream os=new FileOutputStream(dst);
            byte b[]=new byte[10];
            //in.read(b);
            while(in.read(b)!=-1){
                os.write(b);
                //参数1是缓冲数据的数组，参数2是从数组的哪个位置开始转化字符串，参数3是总共转化几个字节
            }

            in.close();
            os.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}