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DatagramChannelImpl 解析三(多播) -
Donald_Draper:
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Memcached分布式客户端(Xmemcached)
Java 理论与实践: 正确使用 Volatile 变量:http://www.ibm.com/developerworks/cn/java/j-jtp06197.html
聊聊并发(一)——深入分析Volatile的实现原理:http://www.infoq.com/cn/articles/ftf-java-volatile
深入理解Java内存模型(四)——volatile:http://www.infoq.com/cn/articles/java-memory-model-4/
Java的多线程机制系列:(四)不得不提的volatile及指令重排序(happen-before):
http://www.cnblogs.com/mengheng/p/3495379.html
CountDownLatch同步化的一个辅助工具,允许一个或多个线程等待,直到所有线程中执行完成
比如主线程计算一个复杂的计算表达式,将表达式分为多个子表达式在线程中去计算,
主线程要计算表达式的最后值,必须等所有的线程计算完子表达式计算,方可计算表达式的值;
再比如一个团队赛跑游戏,最后要计算团队赛跑的成绩,主线程计算最后成绩,要等到所有
团队成员跑完,方可计算总成绩。使用情况两种:第一种,所有线程等待一个开始信息号,当开始信息号启动时,所有线程执行,等待所有线程执行完;第二种,所有线程放在线程池中,执行,等待所有线程执行完,方可执行主线程任务方可执行主线程任务。
测试有统一开始信号的情况:
测试结果:
开始赛跑......
选手3正在赛跑中........
选手2正在赛跑中........
选手1正在赛跑中........
团队赛跑结束,最后成绩为:6000
测试第二种情况,没有开始信号
测试结果:
售票员1卖完一张票,还有:8张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:9张
售票员3卖完一张票,还有:5张
售票员1卖完一张票,还有:6张
售票员3卖完一张票,还有:3张
售票员2卖完一张票,还有:4张
售票员3卖完一张票,还有:1张
售票员1卖完一张票,还有:2张
售票员2卖完一张票,还有:0张
票已售完,所有售票员,停止售票
有时测试结果为:
售票员1卖完一张票,还有:9张
售票员2卖完一张票,还有:8张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:6张
售票员1卖完一张票,还有:5张
售票员3卖完一张票,还有:4张
售票员3卖完一张票,还有:2张
售票员2卖完一张票,还有:1张
售票员1卖完一张票,还有:3张
售票员1卖完一张票,还有:0张
售票员2卖完一张票,还有:-1张
票已售完,所有售票员,停止售票
把Thread.sleep(1000)这句去掉,票数为负数的概率较小,但还是会出现,
我测试了3分钟,出现2次。
关注这一句:
while(tickets.get()>0){
问题可能在tickets.get()的时候,票数不为零,在卖票的时候,其他线程已经在其基础上,修改
tickets,而当前线程tickets.get()已经做过判断,不为零,导致的错误。
再次修改:
测试:
售票员1卖完一张票,还有:9张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:8张
售票员3卖完一张票,还有:5张
售票员1卖完一张票,还有:6张
售票员3卖完一张票,还有:3张
售票员2卖完一张票,还有:4张
售票员2卖完一张票,还有:0张
售票员3卖完一张票,还有:1张
售票员1卖完一张票,还有:2张
票已售完,所有售票员,停止售票
不在出现上述票数为负的情况,关键是添加了所有线程都可见,且线程安全的余票状态
private static volatile AtomicBoolean isDoned = new AtomicBoolean(Boolean.TRUE);
下面来看使用同步锁的场景:
控制台输出:
售票员1卖完一张票,还有:9张
售票员1卖完一张票,还有:8张
售票员1卖完一张票,还有:7张
售票员1卖完一张票,还有:6张
售票员1卖完一张票,还有:5张
售票员1卖完一张票,还有:4张
售票员1卖完一张票,还有:3张
售票员1卖完一张票,还有:2张
售票员3卖完一张票,还有:1张
售票员3卖完一张票,还有:0张
票已售完,所有售票员,停止售票
虽然也可以控制卖票,但只有两个售票员在售票,不能有效的利用资源,达到最大性能。
从上面可以看出,最有效方式为第二种。
聊聊并发(一)——深入分析Volatile的实现原理:http://www.infoq.com/cn/articles/ftf-java-volatile
深入理解Java内存模型(四)——volatile:http://www.infoq.com/cn/articles/java-memory-model-4/
Java的多线程机制系列:(四)不得不提的volatile及指令重排序(happen-before):
http://www.cnblogs.com/mengheng/p/3495379.html
CountDownLatch同步化的一个辅助工具,允许一个或多个线程等待,直到所有线程中执行完成
比如主线程计算一个复杂的计算表达式,将表达式分为多个子表达式在线程中去计算,
主线程要计算表达式的最后值,必须等所有的线程计算完子表达式计算,方可计算表达式的值;
再比如一个团队赛跑游戏,最后要计算团队赛跑的成绩,主线程计算最后成绩,要等到所有
团队成员跑完,方可计算总成绩。使用情况两种:第一种,所有线程等待一个开始信息号,当开始信息号启动时,所有线程执行,等待所有线程执行完;第二种,所有线程放在线程池中,执行,等待所有线程执行完,方可执行主线程任务方可执行主线程任务。
测试有统一开始信号的情况:
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; public class RunnerGames { public static void main(String[] args) { CountDownLatch startSignal = new CountDownLatch(1); CountDownLatch doneSignal = new CountDownLatch(3); ExecutorService exec = Executors.newCachedThreadPool(); RunnableMan rm1 = new RunnableMan(startSignal,doneSignal, 1000); RunnableMan rm2 = new RunnableMan(startSignal,doneSignal, 2000); RunnableMan rm3 = new RunnableMan(startSignal,doneSignal, 3000); Future<Integer> score1 = exec.submit(rm1); Future<Integer> score2 = exec.submit(rm2); Future<Integer> score3 = exec.submit(rm3); System.out.println("开始赛跑......"); startSignal.countDown(); try { doneSignal.await(); } catch (InterruptedException e1) { e1.printStackTrace(); } int sumScores =0; try { try { sumScores = score1.get()+score2.get()+score3.get(); } catch (InterruptedException e) { e.printStackTrace(); } } catch (ExecutionException e) { e.printStackTrace(); } System.out.println("团队赛跑结束,最后成绩为:"+sumScores); exec.shutdown(); } }
package juc; import java.util.concurrent.Callable; import java.util.concurrent.CountDownLatch; class RunnableMan implements Callable<Integer> { private final CountDownLatch startSignal; private final CountDownLatch doneSignal; private final int i; RunnableMan(CountDownLatch startSignal,CountDownLatch doneSignal, int i) { this.startSignal = startSignal; this.doneSignal = doneSignal; this.i = i; } public Integer call() { try { startSignal.await(); doRun(i); } catch (InterruptedException e) { e.printStackTrace(); } doneSignal.countDown(); return new Integer(i); } void doRun(int i) throws InterruptedException { System.out.println("选手"+i/1000+"正在赛跑中........"); Thread.sleep(i*2); } }
测试结果:
开始赛跑......
选手3正在赛跑中........
选手2正在赛跑中........
选手1正在赛跑中........
团队赛跑结束,最后成绩为:6000
测试第二种情况,没有开始信号
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.Executor; import java.util.concurrent.Executors; import java.util.concurrent.atomic.AtomicInteger; /**AtomicInteger,一个提供原子操作的Integer的类。 在Java语言中,++i和i++操作并不是线程安全的,在使用的时候, 不可避免的会用到synchronized关键字。而AtomicInteger则通过一种线程安全的加减操作接口。*/ public class ShopTickets { private static volatile AtomicInteger tickets = new AtomicInteger(10); public static void main(String[] args) throws InterruptedException { CountDownLatch doneSignal = new CountDownLatch(3); Executor exec = Executors.newCachedThreadPool(); exec.execute(new TicketSales(doneSignal,"售票员1",tickets)); exec.execute(new TicketSales(doneSignal,"售票员2",tickets)); exec.execute(new TicketSales(doneSignal,"售票员3",tickets)); doneSignal.await(); System.out.println("票已售完,所有售票员,停止售票"); } }
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.atomic.AtomicInteger; class TicketSales implements Runnable { private final CountDownLatch doneSignal; private final AtomicInteger tickets; private String saleName; TicketSales(CountDownLatch doneSignal, String saleName,AtomicInteger tickets) { this.doneSignal = doneSignal; this.saleName = saleName; this.tickets = tickets; } public void run() { doSales(tickets); } public void doSales(AtomicInteger tickets) { try { while(tickets.get()>0){ System.out.println(saleName+"卖完一张票,还有:"+tickets.decrementAndGet()+"张"); Thread.sleep(1000); } doneSignal.countDown(); }catch (InterruptedException e) { e.printStackTrace(); } } }
测试结果:
售票员1卖完一张票,还有:8张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:9张
售票员3卖完一张票,还有:5张
售票员1卖完一张票,还有:6张
售票员3卖完一张票,还有:3张
售票员2卖完一张票,还有:4张
售票员3卖完一张票,还有:1张
售票员1卖完一张票,还有:2张
售票员2卖完一张票,还有:0张
票已售完,所有售票员,停止售票
有时测试结果为:
售票员1卖完一张票,还有:9张
售票员2卖完一张票,还有:8张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:6张
售票员1卖完一张票,还有:5张
售票员3卖完一张票,还有:4张
售票员3卖完一张票,还有:2张
售票员2卖完一张票,还有:1张
售票员1卖完一张票,还有:3张
售票员1卖完一张票,还有:0张
售票员2卖完一张票,还有:-1张
票已售完,所有售票员,停止售票
把Thread.sleep(1000)这句去掉,票数为负数的概率较小,但还是会出现,
我测试了3分钟,出现2次。
关注这一句:
while(tickets.get()>0){
问题可能在tickets.get()的时候,票数不为零,在卖票的时候,其他线程已经在其基础上,修改
tickets,而当前线程tickets.get()已经做过判断,不为零,导致的错误。
再次修改:
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.Executor; import java.util.concurrent.Executors; import java.util.concurrent.atomic.AtomicInteger; public class ShopTickets2 { /** * AtomicInteger,一个提供原子操作的Integer的类。 在Java语言中,++i和i++操作并不是线程安全的,在使用的时候, * 不可避免的会用到synchronized关键字。而AtomicInteger则通过一种线程安全的加减操作接口。 */ private static volatile AtomicInteger tickets = new AtomicInteger(10); public static void main(String[] args) throws InterruptedException { CountDownLatch doneSignal = new CountDownLatch(3); Executor exec = Executors.newCachedThreadPool(); exec.execute(new TicketSales2(doneSignal, "售票员1", tickets)); exec.execute(new TicketSales2(doneSignal, "售票员2", tickets)); exec.execute(new TicketSales2(doneSignal, "售票员3", tickets)); doneSignal.await(); System.out.println("票已售完,所有售票员,停止售票"); } }
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicInteger; class TicketSales2 implements Runnable { private static volatile AtomicBoolean isDoned = new AtomicBoolean(Boolean.TRUE); private final CountDownLatch doneSignal; private final AtomicInteger tickets; private String saleName; TicketSales2(CountDownLatch doneSignal, String saleName,AtomicInteger tickets) { this.doneSignal = doneSignal; this.saleName = saleName; this.tickets = tickets; } public void run() { doSales(tickets); } public void doSales(AtomicInteger tickets) { while(isDoned.get()){ System.out.println(saleName+"卖完一张票,还有:"+tickets.decrementAndGet()+"张"); if(tickets.get()==0){ isDoned.compareAndSet(true, false); } } doneSignal.countDown(); } }
测试:
售票员1卖完一张票,还有:9张
售票员3卖完一张票,还有:7张
售票员2卖完一张票,还有:8张
售票员3卖完一张票,还有:5张
售票员1卖完一张票,还有:6张
售票员3卖完一张票,还有:3张
售票员2卖完一张票,还有:4张
售票员2卖完一张票,还有:0张
售票员3卖完一张票,还有:1张
售票员1卖完一张票,还有:2张
票已售完,所有售票员,停止售票
不在出现上述票数为负的情况,关键是添加了所有线程都可见,且线程安全的余票状态
private static volatile AtomicBoolean isDoned = new AtomicBoolean(Boolean.TRUE);
下面来看使用同步锁的场景:
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.Executor; import java.util.concurrent.Executors; import java.util.concurrent.atomic.AtomicInteger; public class ShopTickets3 { /** * AtomicInteger,一个提供原子操作的Integer的类。 在Java语言中,++i和i++操作并不是线程安全的,在使用的时候, * 不可避免的会用到synchronized关键字。而AtomicInteger则通过一种线程安全的加减操作接口。 */ private static volatile AtomicInteger tickets = new AtomicInteger(10); private static volatile Object saleLock = new Object(); public static void main(String[] args) throws InterruptedException { CountDownLatch doneSignal = new CountDownLatch(3); Executor exec = Executors.newCachedThreadPool(); exec.execute(new TicketSales3(doneSignal, "售票员1", tickets,saleLock)); exec.execute(new TicketSales3(doneSignal, "售票员2", tickets,saleLock)); exec.execute(new TicketSales3(doneSignal, "售票员3", tickets,saleLock)); doneSignal.await(); System.out.println("票已售完,所有售票员,停止售票"); } }
package juc; import java.util.concurrent.CountDownLatch; import java.util.concurrent.atomic.AtomicInteger; class TicketSales3 implements Runnable { private final CountDownLatch doneSignal; private final AtomicInteger tickets; private final Object saleLock; private String saleName; TicketSales3(CountDownLatch doneSignal, String saleName,AtomicInteger tickets, Object saleLock) { this.doneSignal = doneSignal; this.saleName = saleName; this.tickets = tickets; this.saleLock = saleLock; } public void run() { doSales(tickets); } public void doSales(AtomicInteger tickets) { boolean flag = true; while(flag){ synchronized(saleLock){ if(tickets.get()>0){ System.out.println(saleName+"卖完一张票,还有:"+tickets.decrementAndGet()+"张"); saleLock.notifyAll(); } else{ flag= false; } } } doneSignal.countDown(); } }
控制台输出:
售票员1卖完一张票,还有:9张
售票员1卖完一张票,还有:8张
售票员1卖完一张票,还有:7张
售票员1卖完一张票,还有:6张
售票员1卖完一张票,还有:5张
售票员1卖完一张票,还有:4张
售票员1卖完一张票,还有:3张
售票员1卖完一张票,还有:2张
售票员3卖完一张票,还有:1张
售票员3卖完一张票,还有:0张
票已售完,所有售票员,停止售票
虽然也可以控制卖票,但只有两个售票员在售票,不能有效的利用资源,达到最大性能。
从上面可以看出,最有效方式为第二种。
/* * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. * Written by Doug Lea with assistance from members of JCP JSR-166 * Expert Group and released to the public domain, as explained at * http://creativecommons.org/publicdomain/zero/1.0/ */ package java.util.concurrent; import java.util.concurrent.locks.*; import java.util.concurrent.atomic.*; /** * A synchronization aid that allows one or more threads to wait until * a set of operations being performed in other threads completes. * 同步化的一个辅助工具,允许一个或多个线程等待,直到所有线程中执行完成 *比如主线程计算一个复杂的计算表达式,将表达式分为多个子表达式在线程中去计算, *主线程要计算表达式的最后值,必须等所有的线程计算完子表达式计算,方可计算表达式的值; *再比如一个团队赛跑游戏,最后要计算团队赛跑的成绩,主线程计算最后成绩,要等到所有 *团队成员跑完,方可计算总成绩。 * <p>A {@code CountDownLatch} is initialized with a given [i]count[/i]. * The {@link #await await} methods block until the current count reaches * zero due to invocations of the {@link #countDown} method, after which * all waiting threads are released and any subsequent invocations of * {@link #await await} return immediately. This is a one-shot phenomenon * -- the count cannot be reset. If you need a version that resets the * count, consider using a {@link CyclicBarrier}. *CountDownLatch有一个初始值,调用await的线程,要等待CountDownLatch值为0时,方可 *往下执行 * <p>A {@code CountDownLatch} is a versatile synchronization tool * and can be used for a number of purposes. A * {@code CountDownLatch} initialized with a count of one serves as a * simple on/off latch, or gate: all threads invoking {@link #await await} * wait at the gate until it is opened by a thread invoking {@link * #countDown}. A {@code CountDownLatch} initialized to [i]N[/i] * can be used to make one thread wait until [i]N[/i] threads have * completed some action, or some action has been completed N times. * * <p>A useful property of a {@code CountDownLatch} is that it * doesn't require that threads calling {@code countDown} wait for * the count to reach zero before proceeding, it simply prevents any * thread from proceeding past an {@link #await await} until all * threads could pass. * * <p><b>Sample usage:</b> Here is a pair of classes in which a group * of worker threads use two countdown latches: * [list] * <li>The first is a start signal that prevents any worker from proceeding * until the driver is ready for them to proceed; * <li>The second is a completion signal that allows the driver to wait * until all workers have completed. * [/list] *第一种,所有线程等待一个开始信息号,当开始信息号启动时,所有线程执行,等待所有线程执行完 *方可执行主线程任务 * <pre> * class Driver { // ... * void main() throws InterruptedException { * CountDownLatch startSignal = new CountDownLatch(1); * CountDownLatch doneSignal = new CountDownLatch(N); * * for (int i = 0; i < N; ++i) // create and start threads * new Thread(new Worker(startSignal, doneSignal)).start(); * * doSomethingElse(); // don't let run yet //给所有线程一个开始信号,比如上面的团队赛发令枪 * startSignal.countDown(); // let all threads proceed * doSomethingElse(); //等待所有团队赛跑选手,释放跑完信号 * doneSignal.await(); // wait for all to finish * } * } * * class Worker implements Runnable { * private final CountDownLatch startSignal; * private final CountDownLatch doneSignal; * Worker(CountDownLatch startSignal, CountDownLatch doneSignal) { * this.startSignal = startSignal; * this.doneSignal = doneSignal; * } * public void run() { * try { //等待开始信息号 * startSignal.await(); //赛跑 * doWork(); //跑完,计时员收到跑完信号通知 * doneSignal.countDown(); * } catch (InterruptedException ex) {} // return; * } * * void doWork() { ... } * } * * </pre> * * <p>Another typical usage would be to divide a problem into N parts, * describe each part with a Runnable that executes that portion and * counts down on the latch, and queue all the Runnables to an * Executor. When all sub-parts are complete, the coordinating thread * will be able to pass through await. (When threads must repeatedly * count down in this way, instead use a {@link CyclicBarrier}.) *所有线程放在线程池中,执行,等待所有线程执行完,方可执行主线程任务 * <pre> * class Driver2 { // ... * void main() throws InterruptedException { * CountDownLatch doneSignal = new CountDownLatch(N); * Executor e = ... * * for (int i = 0; i < N; ++i) // create and start threads * e.execute(new WorkerRunnable(doneSignal, i)); * * doneSignal.await(); // wait for all to finish * } * } * * class WorkerRunnable implements Runnable { * private final CountDownLatch doneSignal; * private final int i; * WorkerRunnable(CountDownLatch doneSignal, int i) { * this.doneSignal = doneSignal; * this.i = i; * } * public void run() { * try { * doWork(i); * doneSignal.countDown(); * } catch (InterruptedException ex) {} // return; * } * * void doWork() { ... } * } * * </pre> * * <p>Memory consistency effects: Until the count reaches * zero, actions in a thread prior to calling * {@code countDown()} * [url=package-summary.html#MemoryVisibility]<i>happen-before</i>[/url] * actions following a successful return from a corresponding * {@code await()} in another thread. * * @since 1.5 * @author Doug Lea */ public class CountDownLatch { /** * Synchronization control For CountDownLatch. * Uses AQS state to represent count. *用一个 AQS状态代表信号量数 */ private static final class Sync extends AbstractQueuedSynchronizer { private static final long serialVersionUID = 4982264981922014374L; Sync(int count) { setState(count); } int getCount() { return getState(); } //获取信号量 protected int tryAcquireShared(int acquires) { return (getState() == 0) ? 1 : -1; } //释放信号量 protected boolean tryReleaseShared(int releases) { // Decrement count; signal when transition to zero for (;;) { int c = getState(); if (c == 0) return false; int nextc = c-1; if (compareAndSetState(c, nextc)) return nextc == 0; } } } private final Sync sync; /** * Constructs a {@code CountDownLatch} initialized with the given count. * * @param count the number of times {@link #countDown} must be invoked * before threads can pass through {@link #await} * @throws IllegalArgumentException if {@code count} is negative */ public CountDownLatch(int count) { if (count < 0) throw new IllegalArgumentException("count < 0"); this.sync = new Sync(count); } /** * Causes the current thread to wait until the latch has counted down to * zero, unless the thread is {@linkplain Thread#interrupt interrupted}. * * <p>If the current count is zero then this method returns immediately. * * <p>If the current count is greater than zero then the current * thread becomes disabled for thread scheduling purposes and lies * dormant until one of two things happen: * [list] * <li>The count reaches zero due to invocations of the * {@link #countDown} method; or * <li>Some other thread {@linkplain Thread#interrupt interrupts} * the current thread. * [/list] * * <p>If the current thread: * [list] * <li>has its interrupted status set on entry to this method; or * <li>is {@linkplain Thread#interrupt interrupted} while waiting, * [/list] * then {@link InterruptedException} is thrown and the current thread's * interrupted status is cleared. * * @throws InterruptedException if the current thread is interrupted * while waiting */ public void await() throws InterruptedException { sync.acquireSharedInterruptibly(1); } /** * Causes the current thread to wait until the latch has counted down to * zero, unless the thread is {@linkplain Thread#interrupt interrupted}, * or the specified waiting time elapses. * * <p>If the current count is zero then this method returns immediately * with the value {@code true}. * * <p>If the current count is greater than zero then the current * thread becomes disabled for thread scheduling purposes and lies * dormant until one of three things happen: * [list] * <li>The count reaches zero due to invocations of the * {@link #countDown} method; or * <li>Some other thread {@linkplain Thread#interrupt interrupts} * the current thread; or * <li>The specified waiting time elapses. * [/list] * * <p>If the count reaches zero then the method returns with the * value {@code true}. * * <p>If the current thread: * [list] * <li>has its interrupted status set on entry to this method; or * <li>is {@linkplain Thread#interrupt interrupted} while waiting, * [/list] * then {@link InterruptedException} is thrown and the current thread's * interrupted status is cleared. * * <p>If the specified waiting time elapses then the value {@code false} * is returned. If the time is less than or equal to zero, the method * will not wait at all. * * @param timeout the maximum time to wait * @param unit the time unit of the {@code timeout} argument * @return {@code true} if the count reached zero and {@code false} * if the waiting time elapsed before the count reached zero * @throws InterruptedException if the current thread is interrupted * while waiting */ public boolean await(long timeout, TimeUnit unit) throws InterruptedException { return sync.tryAcquireSharedNanos(1, unit.toNanos(timeout)); } /** * Decrements the count of the latch, releasing all waiting threads if * the count reaches zero. * * <p>If the current count is greater than zero then it is decremented. * If the new count is zero then all waiting threads are re-enabled for * thread scheduling purposes. * * <p>If the current count equals zero then nothing happens. */ public void countDown() { sync.releaseShared(1); } /** * Returns the current count. * * <p>This method is typically used for debugging and testing purposes. * * @return the current count */ public long getCount() { return sync.getCount(); } /** * Returns a string identifying this latch, as well as its state. * The state, in brackets, includes the String {@code "Count ="} * followed by the current count. * * @return a string identifying this latch, as well as its state */ public String toString() { return super.toString() + "[Count = " + sync.getCount() + "]"; } }
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Executors解析
2017-04-07 14:38 1256ThreadPoolExecutor解析一(核心线程池数量、线 ... -
ScheduledThreadPoolExecutor解析三(关闭线程池)
2017-04-06 20:52 4455ScheduledThreadPoolExecutor解析一( ... -
ScheduledThreadPoolExecutor解析二(任务调度)
2017-04-06 12:56 2127ScheduledThreadPoolExecutor解析一( ... -
ScheduledThreadPoolExecutor解析一(调度任务,任务队列)
2017-04-04 22:59 4992Executor接口的定义:http://donald-dra ... -
ThreadPoolExecutor解析四(线程池关闭)
2017-04-03 23:02 9113Executor接口的定义:http: ... -
ThreadPoolExecutor解析三(线程池执行提交任务)
2017-04-03 12:06 6087Executor接口的定义:http://donald-dra ... -
ThreadPoolExecutor解析二(线程工厂、工作线程,拒绝策略等)
2017-04-01 17:12 3041Executor接口的定义:http://donald-dra ... -
ThreadPoolExecutor解析一(核心线程池数量、线程池状态等)
2017-03-31 22:01 20521Executor接口的定义:http://donald-dra ... -
ScheduledExecutorService接口定义
2017-03-29 12:53 1511Executor接口的定义:http://donald-dra ... -
AbstractExecutorService解析
2017-03-29 08:27 1081Executor接口的定义:http: ... -
ExecutorCompletionService解析
2017-03-28 14:27 1595Executor接口的定义:http://donald-dra ... -
CompletionService接口定义
2017-03-28 12:39 1069Executor接口的定义:http://donald-dra ... -
FutureTask解析
2017-03-27 12:59 1330package java.util.concurrent; ... -
Future接口定义
2017-03-26 09:40 1198/* * Written by Doug Lea with ... -
ExecutorService接口定义
2017-03-25 22:14 1164Executor接口的定义:http://donald-dra ... -
Executor接口的定义
2017-03-24 23:24 1678package java.util.concurrent; ... -
简单测试线程池拒绝执行任务策略
2017-03-24 22:37 2031线程池多余任务的拒绝执行策略有四中,分别是直接丢弃任务Disc ... -
JAVA集合类简单综述
2017-03-23 22:51 925Queue接口定义:http://donald-draper. ... -
DelayQueue解析
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SynchronousQueue解析下-TransferQueue
2017-03-22 22:20 2140Queue接口定义:http://donald-draper. ...
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