基于 SSM 框架搭建仿知乎问答平台.zip

package com.javaedge; import java.util.concurrent.*; import java.util.concurrent.atomic.AtomicInteger; class MyThread extends Thread { private int tid; public MyThread(int tid) { this.tid = tid; } @Override public void run() { try { for (int i = 0; i < 10; ++i) { Thread.sleep(1000); System.out.println(String.format("%d:%d", tid, i)); } } catch (Exception e) { e.printStackTrace(); } } } class Consumer implements Runnable { private BlockingQueue<String> q; public Consumer(BlockingQueue<String> q) { this.q = q; } @Override public void run() { try { while (true) { System.out.println(Thread.currentThread().getName() + ":" + q.take()); } } catch (Exception e) { e.printStackTrace(); } } } class Producer implements Runnable { private BlockingQueue<String> q; public Producer(BlockingQueue<String> q) { this.q = q; } @Override public void run() { try { for (int i = 0; i < 100; ++i) { Thread.sleep(1000); q.put(String .valueOf(i)); } } catch (Exception e) { e.printStackTrace(); } } } public class MultiThreadTests { public static void testThread() { for (int i = 0; i < 10; ++i) { //new MyThread(i).start(); } for (int i = 0; i < 10; ++i) { final int finalI = i; new Thread(new Runnable() { @Override public void run() { try { for (int j = 0; j < 10; ++j) { Thread.sleep(1000); System.out.println(String.format("T2 %d: %d:", finalI, j)); } } catch (Exception e) { e.printStackTrace(); } } }).start(); } } private static Object obj = new Object(); public static void testSynchronized1() { synchronized (obj) { try { for (int j = 0; j < 10; ++j) { Thread.sleep(1000); System.out.println(String.format("T3 %d", j)); } } catch (Exception e) { e.printStackTrace(); } } } public static void testSynchronized2() { synchronized (new Object()) { try { for (int j = 0; j < 10; ++j) { Thread.sleep(1000); System.out.println(String.format("T4 %d", j)); } } catch (Exception e) { e.printStackTrace(); } } } public static void testSynchronized() { for (int i = 0; i < 10; ++i) { new Thread(new Runnable() { @Override public void run() { testSynchronized1(); testSynchronized2(); } }).start(); } } public static void testBlockingQueue() { BlockingQueue<String> q = new ArrayBlockingQueue<String>(10); new Thread(new Producer(q)).start(); new Thread(new Consumer(q), "Consumer1").start(); new Thread(new Consumer(q), "Consumer2").start(); } private static ThreadLocal<Integer> threadLocalUserIds = new ThreadLocal<>(); private static int userId; public static void testThreadLocal() { for (int i = 0; i < 10; ++i) { final int finalI = i; new Thread(new Runnable() { @Override public void run() { try { threadLocalUserIds.set(finalI); Thread.sleep(1000); System.out.println("ThreadLocal:" + threadLocalUserIds.get()); } catch (Exception e) { e.printStackTrace(); } } }).start(); } for (int i = 0; i < 10; ++i) { final int finalI = i; new Thread(new Runnable() { @Override public void run() { try { userId = finalI; Thread.sleep(1000); System.out.println("UserId:" + userId); } catch (Exception e) { e.printStackTrace(); } } }).start(); } } public static void testExecutor() { //ExecutorService service = Executors.newSingleThreadExecutor(); ExecutorService service = Executors.newFixedThreadPool(2); service.submit(new Runnable() { @Override public void run() { for (int i = 0; i < 10; ++i) { try { Thread.sleep(1000); System.out.println("Executor1:" + i); } catch (Exception e) { e.printStackTrace(); } } } }); service.submit(new Runnable() { @Override public void run() { for (int i = 0; i < 10; ++i) { try { Thread.sleep(1000); System.out.println("Executor2:" + i); } catch (Exception e) { e.printStackTrace(); } } } }); service.shutdown(); while (!service.isTerminated()) { try { Thread.sleep(1000); System.out.println("Wait for termination."); } catch (Exception e) { e.printStackTrace(); } } } private static int counter = 0; private static AtomicInteger atomicInteger = new AtomicInteger(0); public static void testWithoutAtomic() { for (int i = 0; i < 10; ++i) { new Thread(new Runnable() { @Override public void run() { try { Thread.sleep(1000); for (int j = 0; j < 10; ++j) { counter++; System.out.println(counter); } } catch (Exception e) { e.printStackTrace(); } } }).start(); } } public static void testWithAtomic() { for (int i = 0; i < 10; ++i) { new Thread(new Runnable() { @Override public void run() { try { Thread.sleep(1000); for (int j = 0; j < 10; ++j) { System.out.println(atomicInteger.incrementAndGet()); } } catch (Exception e) { e.printStackTrace(); } } }).start(); } } public static void testAtomic() { //testWithoutAtomic(); testWithAtomic(); } public static void testFuture() { ExecutorService service = Executors.newSingleThreadExecutor(); Future<Integer> future = service.submit(new Callable<Integer>() { @Override public Integer call() throws Exception { //Thread.sleep(1000); throw new IllegalArgumentException("异常"); //return 1; } }); service.shutdown(); try { System.out.println(future.get()); //System.out.println(future.get(100