one hundred and twenty-three thousand four hundred and fifty-six

2 month  

1. loop 

/*public class q1 {
    public static void main(String[] args){
        int i,j;
        for (i=1;i<=9;i++){
            for (j=1;j<=i;j++){
                System.out.print("*");
            }
            System.out.print("\n");
        }
    }
}
*/

2. School 

class Student{
    String name;
    int age;
    static String school = "A university ";
    public Student(String name , int age){
        this.name = name;
        this.age = age;
    }
    public void info() {
        System.out.println(" full name ："+this.name+", Age ："+this.age+", School ："+this.school);
    }
}
public class Example14 {
    public static void main(String[] args){
        Student stu1=new Student(" Zhang San ",18);
        Student stu2=new Student(" Li Si ",19);
        Student stu3=new Student(" Wang Wu ",20);
        stu1.info();
        stu2.info();
        stu3.info();
        stu1.school = "B university ";
        System.out.println(" modify stu1 The school information of the school object is B After college ");
        stu1.info();
        stu2.info();
        stu3.info();
    }
}


3. Sheepdog color 

interface Animal {
    public String NAME = " Shepherd Dog ";
    public void info();
}
interface Color {
    public void black();
}
interface Action extends Animal,Color{
    public void shout();
}
class  Dog implements Action{
    public void info() {
        System.out.println(" name ："+NAME);
    }
    public void black() {
        System.out.println(" black ");
    }
    public void shout() {
        System.out.println(" Wang Wang ......");
    }
}
class Example13 {
    public static void main(String[] args) {
        Dog dog = new Dog();
        dog.info();
        dog.shout();
        dog.black();
    }
}


4. Cat dog polymorphism 

abstract class Animal {
    abstract void shout();
}
class Cat extends Animal {
    public void shout(){
        System.out.println(" Meow meow .......");
    }
}
class Dog extends Animal {
    public void shout() {
        System.out.println(" Wang Wang ......");
    }
}
public class Example14 {
    public static void main(String [] args) {
        Animal an1 = new Cat();
        Animal an2 = new Dog();
        an1.shout();
        an2.shout();
    }
}


5. Xiaohua meow 

interface Animal{
    void shout();
}
public class  floret  {
   public static void main (String [] args) {
       String name = " floret ";
       animalShout(new Animal() {
           @Override
                   public void shout() {
               System.out.println(name+" Meow meow ");
           }
       });
   }
   public static void animalShout(Animal an){
       an.shout();
   }
}



6.io1

import java.io.File;

public class Example1 {
    public static void main(String [] args){
        File f = new File("D:\\file\\a.txt");
        File f1 = new File("src\\Hello.java");
        System.out.println(f);
        System.out.println(f1);
    }
}




7.io2

import java.io.File;
import java.io.IOException;

public class Example3  {
    public static void main(String[]args)throws IOException {
        File f=File.createTempFile("incast-",".txt");
        f.deleteOnExit();
        System.out.println("f Is it a document ："+f.isFile());
        System.out.println("f Relative path of ："+f.getPath());
    }
}



8. Byte stream read 

/*import  java.io.*;
public class ZH1 {
    public static void main(String[] args)throws Exception{
        FileInputStream in=new FileInputStream("test.txt");
        int b=0;
        while(true){
            b=in.read();
            if(b==-1){
                break;
            }
            System.out.println(b);
        }
        in.close();
    }
}
*/



9. Byte stream write 

/*import java.io.*;
public class ZH3 {
    public static void main(String[] args)throws Exception{
        OutputStream out=new FileOutputStream("example2.txt",true);
        String str=" Welcome ";
        byte[] b=str.getBytes();
        for(int i=0;i<b.length;i++){
            out.write(b[i]);
        }
        out.close();
    }
}
*/



10. File replication 

/*import java.io.*;
public class ZH4 {
    public static void main(String[] args)throws Exception{
        InputStream in=new FileInputStream("source/a.png");
        OutputStream out=new FileOutputStream("target/b.png");
        int len;
        long begintime=System.currentTimeMillis();
        while ((len=in.read())!=-1){
            out.write(len);
        }
        long endtime=System.currentTimeMillis();
        System.out.println(" The time spent copying files is :"+(endtime-begintime)+"ms");
        in.close();
        out.close();
    }
}
*/



11. Threads 

/*public class SH2 {
    public static void main(String[] args) {
        MyThread02 myThread02 = new MyThread02();
        myThread02.start();

        while (true){
            System.out.println("main Method is running ");
        }
    }
}
class MyThread02 extends Thread{
    public void run(){
        while (true){
            System.out.println("MyThread Class run() Method is running ");
        }
    }
}
*/



12. Multithreading 

/*public class SH3 {
    public static void main(String[] args) {
        MyThread03 myThread = new MyThread03();
        Thread thread=new Thread(myThread);
        thread.start();
        while (true){
            System.out.println("main() Method is running ");
        }

    }
}
class MyThread03 implements Runnable{
    public void run(){
        while (true){
            System.out.println("MyThread Class run Method is running 0");
        }
    }
}*/



13. Comparison between threading and multithreading 

/*public class SH5 {
    public static void main(String[] args){
        new TicketWindow().start();
        new TicketWindow().start();
        new TicketWindow().start();
        new TicketWindow().start();
    }
}
class TicketWindow extends Thread {
    private int tickets = 100;

    public void run() {
        while (tickets > 0) {
            Thread th = Thread.currentThread();
            String th_name = th.getName();
            System.out.println(th_name + " The second... Is on sale " + tickets-- + " Tickets ");
        }
    }
}*/



14. Selling tickets 

public class SH6 {
    public static void main(String[] args){
        TicketWindow tw=new TicketWindow();
        new Thread(tw," window 1").start();
        new Thread(tw," window 2").start();
        new Thread(tw," window 3").start();
        new Thread(tw," window 4").start();
    }
}
class TicketWindow extends Thread {
    private int tickets = 100;

    public void run() {
        while (tickets > 0) {
            Thread th = Thread.currentThread();
            String th_name = th.getName();
            System.out.println(th_name + " The second... Is on sale " + tickets-- + " Tickets ");
        }
    }
}



15. File replication 2

/*import java.io.*;
public class ZH5 {
    public static void main(String[] args)throws Exception{
        InputStream in=new FileInputStream("source/a.png");
        OutputStream out=new FileOutputStream("target/a.png");
        byte[] buff=new byte[1024];
        int len;
        long begintime=System.currentTimeMillis();
        while ((len= in.read(buff))!=-1){
            out.write(buff,0,len);
        }
        long endtime=System.currentTimeMillis();
        System.out.println(" The time spent copying files is :"+(endtime-begintime)+"ms");
        in.close();
        out.close();
    }
}
*/



16. Pick up io1 after  try finall

public static void main(String[] args)throws Exception{

InputStream input = null;

try{

FileInputStream in = new FileInputStream("test.txt");

int b= 0;

while(true){

b = in.read();

if(b==-1){

break;

}

System.out.println(b);

}

}finally{

if(input!=null){

input.close();

}

}

}