核心线程数和最大线程数的区别
首先看下来自实测的效果图
首先看核心线程够不够用，不够用的话线程数变成了最大线程数的设置，最后队列已经被任务占满了，抛出异常
首先使用核心线程
然后采用最大线程
以上就是核心线程数和最大线程数的区别
代码部分
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.7.8</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.web</groupId> <artifactId>web-study</artifactId> <version>0.0.1-SNAPSHOT</version> <name>web-study</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!--ThreadFactoryBuilder的依赖包,多线程使用--> <dependency> <groupId>com.google.guava</groupId> <artifactId>guava</artifactId> <version>30.1-jre</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project>
package com.web.webstudy.test;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;
/**
* @Description:
* @Author: Yourheart
* @Create: 2023/2/10 17:21
*/
public class CustomThreadFactory implements ThreadFactory {
private static final AtomicInteger poolNumber = new AtomicInteger(1);
private final ThreadGroup group;
private final AtomicInteger threadNumber = new AtomicInteger(1);
private final String namePrefix;
public CustomThreadFactory() {
SecurityManager s = System.getSecurityManager();
group = (s != null) ? s.getThreadGroup() :
Thread.currentThread().getThreadGroup();
namePrefix = "线程池数量-" +
poolNumber.getAndIncrement() +
"-线程名称-";
}
@Override
public Thread newThread(Runnable r) {
Thread t = new Thread(group, r,
namePrefix + threadNumber.getAndIncrement() + "",
0);
if (t.isDaemon()){
t.setDaemon(false);
}
if (t.getPriority() != Thread.NORM_PRIORITY){
t.setPriority(Thread.NORM_PRIORITY);
}
return t;
}
}
package com.web.webstudy;
import com.web.webstudy.test.CustomThreadFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;
import java.util.concurrent.*;
/**
* @Description: 自定义线程池
* @Author: Yourheart
* @Create: 2023/2/9 10:38
*/
@Component
public class ThreadPool {
@Bean
public ThreadPoolExecutor threadPoolExecutor() {
//核心线程数
int corePoolSize = 2;
//最大线程数
int maximumPoolSize = 5;
//超过 corePoolSize 线程数量的线程最大空闲时间
long keepAliveTime = 0;
//以秒为时间单位
TimeUnit unit = TimeUnit.SECONDS;
//创建工作队列，用于存放提交的等待执行任务
BlockingQueue<Runnable> workQueue = new ArrayBlockingQueue<Runnable>(10);
ThreadFactory threadFactory = new CustomThreadFactory();
ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(corePoolSize,
maximumPoolSize,
keepAliveTime,
unit,
workQueue,
threadFactory,
new ThreadPoolExecutor.AbortPolicy());
return threadPoolExecutor;
}
}
package com.web.webstudy;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.concurrent.ThreadPoolExecutor;
/**
* @Description:
* @Author: Yourheart
* @Create: 2023/2/9 10:44
*/
@RestController
@Slf4j
public class ThreadPoolController {
@Autowired
private ThreadPoolExecutor threadPoolExecutor;
@RequestMapping("/test")
public String test(int threadPoolNum,int threadNum){
for (int i=0;i<threadPoolNum;i++){
for (int k=0;k<threadNum;k++){
threadPoolExecutor.execute(new ThreadPoolTest(k));
}
}
return "success";
}
}
package com.web.webstudy;
import lombok.extern.slf4j.Slf4j;
/**
* @Description:
* @Author: Yourheart
* @Create: 2023/2/9 10:43
*/
@Slf4j
public class ThreadPoolTest implements Runnable {
private int count;
public ThreadPoolTest(int count) {
this.count = count;
}
@Override
public void run() {
String name = Thread.currentThread().getName();
log.info("线程名称:{},count:{}",name,count);
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
package com.web.webstudy;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class WebStudyApplication {
public static void main(String[] args) {
SpringApplication.run(WebStudyApplication.class, args);
}
}
我这边采用的接口调用的方式进行的测试的
接口地址 http://127.0.0.1:8080/test?threadPoolNum=1&threadNum=10
