Пример Spring и Java Thread
Вот 3 примера, которые покажут вам, как выполнить «threading» в Spring. См код для самоочевидного.
1. Пример Spring + Java Threads
Создайте простой поток Java, расширивThread и управляемый контейнером Spring через@Component. Область действия bean-компонента должна быть «prototype», чтобы каждый запрос возвращал новый экземпляр для запуска каждого отдельного потока.
PrintThread.java
package com.example.thread;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Component;
@Component
@Scope("prototype")
public class PrintThread extends Thread{
@Override
public void run() {
System.out.println(getName() + " is running");
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(getName() + " is running");
}
}
AppConfig.java
package com.example.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan(basePackages="com.example.thread")
public class AppConfig{
}
App.java
package com.example;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import com.example.config.AppConfig;
import com.example.thread.PrintThread;
public class App
{
public static void main( String[] args )
{
ApplicationContext ctx = new AnnotationConfigApplicationContext(AppConfig.class);
PrintThread printThread1 = (PrintThread) ctx.getBean("printThread");
printThread1.setName("Thread 1");
PrintThread printThread2 = (PrintThread) ctx.getBean("printThread");
printThread2.setName("Thread 2");
PrintThread printThread3 = (PrintThread) ctx.getBean("printThread");
printThread3.setName("Thread 3");
PrintThread printThread4 = (PrintThread) ctx.getBean("printThread");
printThread4.setName("Thread 4");
PrintThread printThread5 = (PrintThread) ctx.getBean("printThread");
printThread5.setName("Thread 5");
printThread1.start();
printThread2.start();
printThread3.start();
printThread4.start();
printThread5.start();
}
}
Вывод - порядок будет меняться каждый раз, это нить :)
Thread 3 is running Thread 2 is running Thread 1 is running Thread 5 is running Thread 4 is running Thread 2 is running Thread 4 is running Thread 5 is running Thread 3 is running Thread 1 is running
2. Spring Thread Pool + пример неуправляемого компонента Spring
Использует SpringThreadPoolTaskExecutor для создания пула потоков. Выполняющий поток не обязательно управляется контейнером Spring.
PrintThread.java – This thread is not managed by Spring, NO @Component
package com.example.thread;
public class PrintTask implements Runnable{
String name;
public PrintTask(String name){
this.name = name;
}
@Override
public void run() {
System.out.println(name + " is running");
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(name + " is running");
}
}
Spring-Config.xml – ThreadPoolTaskExecutor in XML file
App.java
package com.example;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import com.example.thread.PrintTask;
public class App {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("Spring-Config.xml");
ThreadPoolTaskExecutor taskExecutor = (ThreadPoolTaskExecutor) context.getBean("taskExecutor");
taskExecutor.execute(new PrintTask("Thread 1"));
taskExecutor.execute(new PrintTask("Thread 2"));
taskExecutor.execute(new PrintTask("Thread 3"));
taskExecutor.execute(new PrintTask("Thread 4"));
taskExecutor.execute(new PrintTask("Thread 5"));
//check active thread, if zero then shut down the thread pool
for (;;) {
int count = taskExecutor.getActiveCount();
System.out.println("Active Threads : " + count);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (count == 0) {
taskExecutor.shutdown();
break;
}
}
}
}
Вывод - порядок будет меняться каждый раз.
Thread 1 is running Thread 2 is running Thread 3 is running Thread 4 is running Active Threads : 4 Thread 5 is running Active Threads : 5 Active Threads : 5 Active Threads : 5 Active Threads : 5 Thread 2 is running Thread 1 is running Thread 3 is running Thread 4 is running Thread 5 is running Active Threads : 0
3. Spring Thread Pool + пример управляемого боба Spring
В этом примере снова используетсяThreadPoolTaskExecutor, и поток объявляется как управляемый компонент Spring через@Component.
НижеPrintTask2 - это управляемый bean-компонент Spring, вы можете легко@Autowired использовать любые требуемые bean-компоненты.
PrintTask2.java
package com.example.thread;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Component;
@Component
@Scope("prototype")
public class PrintTask2 implements Runnable{
String name;
public void setName(String name){
this.name = name;
}
@Override
public void run() {
System.out.println(name + " is running");
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(name + " is running");
}
}
AppConfig.java – ThreadPoolTaskExecutor in Spring configuration file
package com.example.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
@Configuration
@ComponentScan(basePackages = "com.example.thread")
public class AppConfig {
@Bean
public ThreadPoolTaskExecutor taskExecutor() {
ThreadPoolTaskExecutor pool = new ThreadPoolTaskExecutor();
pool.setCorePoolSize(5);
pool.setMaxPoolSize(10);
pool.setWaitForTasksToCompleteOnShutdown(true);
return pool;
}
}
App.java
package com.example;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import com.example.config.AppConfig;
import com.example.thread.PrintTask2;
public class App {
public static void main(String[] args) {
ApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);
ThreadPoolTaskExecutor taskExecutor = (ThreadPoolTaskExecutor) context.getBean("taskExecutor");
PrintTask2 printTask1 = (PrintTask2) context.getBean("printTask2");
printTask1.setName("Thread 1");
taskExecutor.execute(printTask1);
PrintTask2 printTask2 = (PrintTask2) context.getBean("printTask2");
printTask2.setName("Thread 2");
taskExecutor.execute(printTask2);
PrintTask2 printTask3 = (PrintTask2) context.getBean("printTask2");
printTask3.setName("Thread 3");
taskExecutor.execute(printTask3);
for (;;) {
int count = taskExecutor.getActiveCount();
System.out.println("Active Threads : " + count);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (count == 0) {
taskExecutor.shutdown();
break;
}
}
}
}
Вывод - порядок будет меняться каждый раз.
Thread 1 is running Thread 2 is running Thread 3 is running Active Threads : 2 Active Threads : 3 Active Threads : 3 Active Threads : 3 Active Threads : 3 Thread 1 is running Thread 3 is running Thread 2 is running Active Threads : 0
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