Common examples of Java multithreading __java

Common examples of Java multithreading

Author: narcisoforher

Reprint: Click to read the full text view

I. Related knowledge:

Java multithreaded programming to the knowledge:

(i) operation of the same quantity

(ii) operation of the same object

(iii) The callback method uses

(iv) Thread synchronization, deadlock problem

(v) Thread communication

Wait a minute

Two Example one: Three ticket windows sell 20 tickets at the same time;

Program analysis: 1. Vote number to use the same static value

2. To ensure that there will not be sold the same number of votes, to Java multithreaded synchronization lock.

Design idea: 1. Create a platform class station, inherit thread, rewrite the Run method, and perform ticketing operations in the Run method. Ticket sales to use the Sync Lock: There is a platform to sell this ticket, the other platform to wait for this ticket sold out.

2. Create the Main method invocation class

(a) Create a platform class, inherit thread

Package com.xykj.threadStation;

public class Station extends Thread {

To assign a value to a thread name by constructing a method
Public Station (String name) {
Super (name);//Assign value to thread name
}

In order to keep the number of votes consistent, the number of votes to be static
static int tick = 20;

Create a static key
static Object ob = "AA";//value is arbitrary

Rewrite the Run method to achieve the ticket operation
@Override
public void Run () {
while (tick > 0) {
Synchronized (OB) {//This is important, you must use a lock,
The man who goes in will hold the key in his hand and come out to get the key.
if (Tick > 0) {
System.out.println (GetName () + "sold the first" + Tick + "ticket");
tick--;
} else {
System.out.println ("tickets sold out");
}
}
try {
Sleep (1000);//Rest One second
catch (Interruptedexception e) {
E.printstacktrace ();
}

}
}

}

(ii) Creating the Main method invocation class

Package com.xykj.threadStation;

public class MainClass {
/**
* Use of Java multithreaded synchronous locks
* Example: three ticket window selling 10 tickets at the same time
* */
public static void Main (string[] args) {
Instantiate the platform object and name each platform
Station Station1=new Station ("Window 1");
Station Station2=new Station ("Window 2");
Station Station3=new Station ("Window 3");

Let each platform object start its own work
Station1.start ();
Station2.start ();
Station3.start ();

}

}

Program Run Result:

You can see the number of votes is not wrong.

Three Example two: Two people ab through an account a at the counter to take money and B to withdraw money at the ATM machine.

Program Analysis: The amount of money to be set into a static variable. Two people to take the same object value

(a) Create a bank class

 package Com.xykj.bank; 
   
 public class bank {
   
//Suppose an account has 1000 dollars 
 Static int money =  1000; 
   
//Counter Counter the way to withdraw the money 
 Public void counter (Int money)  {//parameter is the money taken each time 
 Bank.money-= money;