并发测试 JavaDemo

https://github.com/oldratlee/fucking-java-concurrency

     

         

             


             
         
         

             

             
 
         
         

             

             
/**
         
         

             

             
 * @author Jerry Lee
         
         

             

             
 */
         
         

             

             
public class Testee {
         
         

             

             
 static long countTimeIn500ms = 0;
         
         

             

             
 
         
         

             

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

             

             
 countTimeIn500ms = guessCountTimeIn500ms();
         
         

             

             
 
         
         

             

             
 Thread runAndSleepTask = new Thread(new RunAndSleepTask(), "RunAndSleepTask");
         
         

             

             
 Thread runAndWaitTask = new Thread(new RunAndWaitTask(), "RunAndWaitTask");
         
         

             

             
 Thread runAndLongSleepTask = new Thread(new RunAndLongSleepTask(), "RunAndLongSleepTask");
         
         

             

             
 
         
         

             

             
 runAndSleepTask.start();
         
         

             

             
 runAndWaitTask.start();
         
         

             

             
 runAndLongSleepTask.start();
         
         

             

             
 
         
         

             

             
 System.out.println("Tasks started!");
         
         

             

             
 Thread.sleep(Long.MAX_VALUE);
         
         

             

             
 }
         
         

             

             
 
         
         

             

             
 public static class RunAndSleepTask implements Runnable {
         
         

             

             
 @Override
         
         

             

             
 public void run() {
         
         

             

             
 String name = this.getClass().getSimpleName();
         
         

             

             
 while (true) {
         
         

             

             
 for (long i = 0; i < countTimeIn500ms; i++) {
         
         

             

             
 }
         
         

             

             
 System.out.println(name + ": " + new Date());
         
         

             

             
 try {
         
         

             

             
 Thread.sleep(500);
         
         

             

             
 } catch (InterruptedException e) {
         
         

             

             
 e.printStackTrace();
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 
         
         

             

             
 public static class RunAndWaitTask implements Runnable {
         
         

             

             
 @Override
         
         

             

             
 public void run() {
         
         

             

             
 String name = this.getClass().getSimpleName();
         
         

             

             
 while (true) {
         
         

             

             
 for (long i = 0; i < countTimeIn500ms; i++) {
         
         

             

             
 }
         
         

             

             
 try {
         
         

             

             
 System.out.println(name + ": " + new Date());
         
         

             

             
 synchronized (this) {
         
         

             

             
 this.wait(500);
         
         

             

             
 }
         
         

             

             
 } catch (InterruptedException e) {
         
         

             

             
 e.printStackTrace();
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 
         
         

             

             
 public static class RunAndLongSleepTask implements Runnable {
         
         

             

             
 @Override
         
         

             

             
 public void run() {
         
         

             

             
 String name = this.getClass().getSimpleName();
         
         

             

             
 while (true) {
         
         

             

             
 for (long i = 0; i < countTimeIn500ms; i++) {
         
         

             

             
 }
         
         

             

             
 System.out.println(name + ": " + new Date());
         
         

             

             
 try {
         
         

             

             
 Thread.sleep(5000);
         
         

             

             
 } catch (InterruptedException e) {
         
         

             

             
 e.printStackTrace();
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 }
         
         

             

             
 
         
         

             

             
 /**
         
         

             

             
 * @return 100ms可以做{@code long}的计数次数。
         
         

             

             
 */
         
         

             

             
 static long guessCountTimeIn500ms() {
         
         

             

             
 System.out.println("start guess.");
         
         

             

             
 
         
         

             

             
 long count = 1000L * 1000 * 1000;
         
         

             

             
 
         
         

             

             
 // simple warm-up
         
         

             

             
 for (long i = 0; i < count; i++) {
         
         

             

             
 // nothing!
         
         

             

             
 }
         
         

             

             
 
         
         

             

             
 long tick = System.currentTimeMillis();
         
         

             

             
 for (long i = 0; i < count; i++) {
         
         

             

             
 // nothing!
         
         

             

             
 }
         
         

             

             
 long duration = System.currentTimeMillis() - tick;
         
         

             

             
 System.out.printf("1G times count take %d ms.\n", duration);
         
         

             

             
 
         
         

             

             
 return count * 500 / duration;
         
         

             

             
 }
         
         

             

             
}