Easily learn multi-threading-06-Producer Consumer mode

Producer Consumer Pattern

The Producer Consumer mode means that one is responsible for production and the other is responsible for consumption.

The core is that the producer securely hands the data to the consumer.

actual case

Overview of class information:

class name	illustrate
Main.java	general entry for the method
ConsumerCakeThread.java	thread that consumes cake
Table.java	table for cakes
BlockingQueueTable.java	BlockingQueue implementation
ProducerCakeThread.java	thread producing cake

definition

• ConsumerCakeThread.java

package com.github.houbb.thread.learn.easy.learn.producer.consumer;

import java.util.Random;

public class ConsumerCakeThread extends Thread {

    private String name;

    private final Table table;

    public ConsumerCakeThread(String name, Table table) {
        super(name);
        this.table = table;
    }

    @Override
    public void run() {
        Random random = new Random(1000L);
        try {
            while(true) {
                Thread.sleep(random.nextInt(1000));
                String cake = table.take();
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

}

• Table.java

package com.github.houbb.thread.learn.easy.learn.producer.consumer;

/**
 * @see BlockingQueueTable 可以被这个替换
 */
public class Table {

    /**
     * 存放蛋糕的数组
     */
    private String[] cakeArray;

    /**
     * 头
     */
    private int head;

    /**
     * 尾巴
     */
    private int tail;

    private int count;

    private final int size;


    public Table(int size) {
        this.size = size;
        cakeArray = new String[size];
        this.head = 0;
        this.tail = 0;
        this.count = 0;
    }

    public synchronized void put(final String cakeName) throws InterruptedException {
        while(count >= size) {
            wait();
        }

        cakeArray[tail] = cakeName;
        count++;
        tail = (tail + 1) % size;
        System.out.println(Thread.currentThread().getName() + " put cake " + cakeName);

        notifyAll();
    }

    public synchronized String take() throws InterruptedException {
        while (count <= 0) {
            wait();
        }

        String result = cakeArray[head];
        head = (head + 1) % size;
        count--;

        System.out.println(Thread.currentThread().getName() + " take cake " + result);
        notifyAll();

        return result;
    }

}

• BlockingQueueTable.java

package com.github.houbb.thread.learn.easy.learn.producer.consumer;

import java.util.concurrent.ArrayBlockingQueue;

/**
 * 使用 queue
 */
public class BlockingQueueTable extends ArrayBlockingQueue<String> {

    public BlockingQueueTable(int size) {
        super(size);
    }

    public void put(final String cakeName) throws InterruptedException {
        super.put(cakeName);
    }

    public String take() throws InterruptedException {
        return super.take();
    }

}

• ProducerCakeThread.java

package com.github.houbb.thread.learn.easy.learn.producer.consumer;

import java.util.Random;

public class ProducerCakeThread extends Thread {

    private final Table table;

    private static int id = 0;

    public ProducerCakeThread(String name, Table table) {
        super(name);
        this.table = table;
    }

    @Override
    public void run() {
        Random random = new Random(1000L);
        try {
            while(true) {
                String cakeName = getName()+"-"+genId();
                Thread.sleep(random.nextInt(1000));
                table.put(cakeName);
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    private static synchronized int genId() {
        return id++;
    }

}

test

• Main.java

package com.github.houbb.thread.learn.easy.learn.producer.consumer;

public class Main {

    public static void main(String[] args) {
        Table table = new Table(3);
        new ConsumerCakeThread("ConsumerCake", table).start();
        new ProducerCakeThread("ProducerCake", table).start();
    }

}

• Test Results

ProducerCake put cake ProducerCake-0
ConsumerCake take cake ProducerCake-0
ProducerCake put cake ProducerCake-1
ConsumerCake take cake ProducerCake-1
ProducerCake put cake ProducerCake-2
ConsumerCake take cake ProducerCake-2
ProducerCake put cake ProducerCake-3
ConsumerCake take cake ProducerCake-3
ProducerCake put cake ProducerCake-4
ConsumerCake take cake ProducerCake-4
ProducerCake put cake ProducerCake-5
ConsumerCake take cake ProducerCake-5

Method to realize

UML & Code

UML

The UML diagram is as follows

Code

code address

Producer Consumer

Series Navigation

Multithreaded series navigation