并发编程与高并发解决方案学习(J.U.C之AQS-CountDownLatch、Semaphore)_c高并发解决方案-程序员宅基地

※使用Node实现FIFO队列，可以用于构建锁或者其他同步装置的基础框架

※利用int类型表示状态 state=0表示还没有线程获取锁 state=1表示有现成获取锁，大于1表示可重入锁数量

※使用方法是继承 AQS使用模板方法模式，继承模板方法，复写其中的方法

※子类通过继承并通过实现它的方法管理其状态{acquire和release}的方法操作状态

※可以同时实现排它锁和共享锁模式(
独占、共享)

AQS同步组件（
CountDownLatch、Semaphore、CyclicBarrier、ReentrantLock、Condition、FutureTask）

CountDownLatch(作用类似于join())
 同步辅助类，可以实现阻塞的作用，同一时间只能有一个线程操作该计数器，调用该类的await类会一直处于阻塞状态，直到其他线程调用countDown方法，使当前计数器的值为0（计数器不可以重置）

使用场景：程序执行需要等待某个条件完成之后才能继续执行后续的操作，典型应用例如：并行计算（ 当某个处理的运算量很大的时候，可以将该运算任务拆分为多个子任务，等待所有子任务都执行完之后，父任务再拿到所有子任务运行结果进行汇总）。

import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

@Slf4j
public class CountDownLatchExample1 {
    private final static int threadCount = 20;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final CountDownLatch countDownLatch = new CountDownLatch(threadCount);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    test(threadNum);
                } catch (Exception e) {
                    log.error("exception", e);
                } finally {
                    countDownLatch.countDown();
                }
            });
        }
        countDownLatch.await();
        log.info("finish");
        exec.shutdown();
    }

    private static  void test(int threadNum) throws Exception {
        Thread.sleep(100);
        log.info("{}", threadNum);
        Thread.sleep(100);
    }
}

输出结果

15:54:06.904 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 0
15:54:06.904 [pool-1-thread-8] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 7
15:54:06.905 [pool-1-thread-19] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 18
15:54:06.904 [pool-1-thread-6] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 5
15:54:06.904 [pool-1-thread-7] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 6
15:54:06.904 [pool-1-thread-4] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 3
15:54:06.904 [pool-1-thread-5] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 4
15:54:06.904 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 2
15:54:06.904 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 1
15:54:06.904 [pool-1-thread-9] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 8
15:54:06.905 [pool-1-thread-18] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 17
15:54:06.904 [pool-1-thread-10] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 9
15:54:06.905 [pool-1-thread-17] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 16
15:54:06.904 [pool-1-thread-11] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 10
15:54:06.905 [pool-1-thread-20] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 19
15:54:06.905 [pool-1-thread-16] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 15
15:54:06.905 [pool-1-thread-13] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 12
15:54:06.904 [pool-1-thread-12] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 11
15:54:06.905 [pool-1-thread-15] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 14
15:54:06.905 [pool-1-thread-14] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - 13
15:54:07.009 [main] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample1 - finish

案例2（起了很多线程去完成任务，但是这个任务指向给指定的时间，操作这个时间没做完，也不管了）

import lombok.extern.slf4j.Slf4j;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

@Slf4j
public class CountDownLatchExample2 {
    private final static int threadCount = 200;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final CountDownLatch countDownLatch = new CountDownLatch(threadCount);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    test(threadNum);
                } catch (Exception e) {
                    log.error("exception", e);
                } finally {
                    countDownLatch.countDown();
                }
            });
        }
        countDownLatch.await(10, TimeUnit.MILLISECONDS);
        log.info("finish");
        exec.shutdown();
    }

    private static void test(int threadNum) throws Exception {
        Thread.sleep(1000);
        log.info("{}", threadNum);
    }
}

输出结果

15:57:13.433 [main] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - finish
15:57:14.423 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 0
15:57:14.435 [pool-1-thread-4] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 3
15:57:14.436 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 2
15:57:14.436 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 1
15:57:14.438 [pool-1-thread-5] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 4
15:57:14.441 [pool-1-thread-8] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 7
15:57:14.442 [pool-1-thread-7] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 6
15:57:14.442 [pool-1-thread-6] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 5
15:57:14.442 [pool-1-thread-11] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 10
15:57:14.443 [pool-1-thread-10] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 9
15:57:14.443 [pool-1-thread-9] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 8
15:57:14.443 [pool-1-thread-13] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 12
15:57:14.443 [pool-1-thread-12] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 11
15:57:14.443 [pool-1-thread-15] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 14
15:57:14.444 [pool-1-thread-14] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 13
15:57:14.444 [pool-1-thread-20] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 19
15:57:14.444 [pool-1-thread-19] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 18
15:57:14.447 [pool-1-thread-18] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 17
15:57:14.447 [pool-1-thread-16] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 15
15:57:14.447 [pool-1-thread-17] INFO com.mmall.concurrency.example.aqs.CountDownLatchExample2 - 16

调用shutdown并不是第一时间将线程都全部销毁掉，而是让当前已有的线程全部执行完，之后再把这个线程池销毁掉。

Semaphore 信号量(控制并发访问的线程个数，类似于有限的链表，常用语仅能提供有限个访问的资源,比如 控制数据库连接数)

import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;

@Slf4j
public class SemaphoreExample1 {
    private final static int threadCount = 20;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final Semaphore semaphore = new Semaphore(3);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    semaphore.acquire(); // 每次获取一个许可
                    test(threadNum);
                    semaphore.release(); // 每次释放一个许可
                } catch (Exception e) {
                    log.error("exception", e);
                }
            });
        }
        exec.shutdown();
    }

    private static void test(int threadNum) throws Exception {
        log.info("{}", threadNum);
        Thread.sleep(1000);
    }
}

输出结果(一次3条输出)

15:59:19.291 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 1
15:59:19.291 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 0
15:59:19.291 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 2
15:59:20.309 [pool-1-thread-4] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 3
15:59:20.310 [pool-1-thread-5] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 4
15:59:20.310 [pool-1-thread-6] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 5
15:59:21.310 [pool-1-thread-7] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 6
15:59:21.310 [pool-1-thread-8] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 7
15:59:21.311 [pool-1-thread-9] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 8
15:59:22.310 [pool-1-thread-10] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 9
15:59:22.310 [pool-1-thread-11] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 10
15:59:22.311 [pool-1-thread-12] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 11
15:59:23.311 [pool-1-thread-13] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 12
15:59:23.311 [pool-1-thread-14] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 13
15:59:23.312 [pool-1-thread-15] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 14
15:59:24.311 [pool-1-thread-16] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 15
15:59:24.311 [pool-1-thread-17] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 16
15:59:24.312 [pool-1-thread-18] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 17
15:59:25.312 [pool-1-thread-20] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 19
15:59:25.312 [pool-1-thread-19] INFO com.mmall.concurrency.example.aqs.SemaphoreExample1 - 18

import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;

@Slf4j
public class SemaphoreExample2 {
    private final static int threadCount = 20;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final Semaphore semaphore = new Semaphore(3);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    semaphore.acquire(3); // 每次获取多个许可
                    test(threadNum);
                    semaphore.release(3); // 每次释放多个许可
                } catch (Exception e) {
                    log.error("exception", e);
                }
            });
        }
        exec.shutdown();
    }

    private static void test(int threadNum) throws Exception {
        log.info("{}", threadNum);
        Thread.sleep(1000);
    }
}

输出结果（一次一条输出）

16:00:37.474 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 0
16:00:38.480 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 1
16:00:39.480 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 2
16:00:40.481 [pool-1-thread-4] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 3
16:00:41.482 [pool-1-thread-5] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 4
16:00:42.482 [pool-1-thread-6] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 5
16:00:43.483 [pool-1-thread-7] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 6
16:00:44.483 [pool-1-thread-8] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 7
16:00:45.484 [pool-1-thread-9] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 8
16:00:46.484 [pool-1-thread-10] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 9
16:00:47.484 [pool-1-thread-11] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 10
16:00:48.485 [pool-1-thread-12] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 11
16:00:49.485 [pool-1-thread-13] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 12
16:00:50.485 [pool-1-thread-14] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 13
16:00:51.486 [pool-1-thread-15] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 14
16:00:52.486 [pool-1-thread-17] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 16
16:00:53.486 [pool-1-thread-16] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 15
16:00:54.486 [pool-1-thread-18] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 17
16:00:55.487 [pool-1-thread-19] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 18
16:00:56.488 [pool-1-thread-20] INFO com.mmall.concurrency.example.aqs.SemaphoreExample2 - 19

案例（假如当前并发数是3，超过3个就丢弃）

import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;

@Slf4j
public class SemaphoreExample3 {
    private final static int threadCount = 20;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final Semaphore semaphore = new Semaphore(3);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    if (semaphore.tryAcquire()) { // 尝试获取一个许可
                        test(threadNum);
                        semaphore.release(); // 释放一个许可
                    }
                } catch (Exception e) {
                    log.error("exception", e);
                }
            });
        }
        exec.shutdown();
    }

    private static void test(int threadNum) throws Exception {
        log.info("{}", threadNum);
        Thread.sleep(1000);
    }
}

输出结果

16:01:45.406 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.SemaphoreExample3 - 1
16:01:45.405 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.SemaphoreExample3 - 0
16:01:45.413 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.SemaphoreExample3 - 2

尝试获得许可，只让执行5秒

import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;

@Slf4j
public class SemaphoreExample4 {
    private final static int threadCount = 20;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final Semaphore semaphore = new Semaphore(3);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            exec.execute(() -> {
                try {
                    if (semaphore.tryAcquire(5000, TimeUnit.MILLISECONDS)) { // 尝试获取一个许可
                        test(threadNum);
                        semaphore.release(); // 释放一个许可
                    }
                } catch (Exception e) {
                    log.error("exception", e);
                }
            });
        }
        exec.shutdown();
    }

    private static void test(int threadNum) throws Exception {
        log.info("{}", threadNum);
        Thread.sleep(1000);
    }
}

输出结果(一次三条输出)

16:02:31.454 [pool-1-thread-3] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 2
16:02:31.454 [pool-1-thread-1] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 0
16:02:31.454 [pool-1-thread-2] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 1
16:02:32.463 [pool-1-thread-4] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 3
16:02:32.464 [pool-1-thread-5] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 4
16:02:32.464 [pool-1-thread-6] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 5
16:02:33.464 [pool-1-thread-8] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 7
16:02:33.464 [pool-1-thread-7] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 6
16:02:33.465 [pool-1-thread-9] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 8
16:02:34.465 [pool-1-thread-10] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 9
16:02:34.465 [pool-1-thread-11] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 10
16:02:34.466 [pool-1-thread-12] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 11
16:02:35.465 [pool-1-thread-13] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 12
16:02:35.466 [pool-1-thread-14] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 13
16:02:35.466 [pool-1-thread-15] INFO com.mmall.concurrency.example.aqs.SemaphoreExample4 - 14

本文链接：https://blog.csdn.net/Andy2019/article/details/79784000

原作者删帖不实内容删帖广告或垃圾文章投诉

智能推荐

class和struct的区别-程序员宅基地

文章浏览阅读101次。4.class可以有⽆参的构造函数，struct不可以，必须是有参的构造函数，⽽且在有参的构造函数必须初始。2.Struct适⽤于作为经常使⽤的⼀些数据组合成的新类型，表示诸如点、矩形等主要⽤来存储数据的轻量。1.Class⽐较适合⼤的和复杂的数据，表现抽象和多级别的对象层次时。2.class允许继承、被继承，struct不允许，只能继承接⼝。3.Struct有性能优势，Class有⾯向对象的扩展优势。3.class可以初始化变量，struct不可以。1.class是引⽤类型，struct是值类型。

android使用json后闪退,应用闪退问题：从json信息的解析开始就会闪退-程序员宅基地

文章浏览阅读586次。想实现的功能是点击顶部按钮之后按关键字进行搜索，已经可以从服务器收到反馈的json信息，但从json信息的解析开始就会闪退，加载listview也不知道行不行public abstract class loadlistview{public ListView plv;public String js;public int listlength;public int listvisit;public..._rton转json为什么会闪退

如何使用wordnet词典，得到英文句子的同义句_get_synonyms wordnet-程序员宅基地

文章浏览阅读219次。如何使用wordnet词典，得到英文句子的同义句_get_synonyms wordnet

系统项目报表导出功能开发_积木报表多线程-程序员宅基地

文章浏览阅读521次。系统项目报表导出导出任务队列表 + 定时扫描 + 多线程_积木报表多线程

ajax 如何从服务器上获取数据？_ajax 获取http数据-程序员宅基地

文章浏览阅读1.1k次，点赞9次，收藏9次。使用AJAX技术的好处之一是它能够提供更好的用户体验，因为它允许在不重新加载整个页面的情况下更新网页的某一部分。另外，AJAX还使得开发人员能够创建更复杂、更动态的Web应用程序，因为它们可以在后台与服务器进行通信，而不需要打断用户的浏览体验。在Web开发中，AJAX（Asynchronous JavaScript and XML）是一种常用的技术，用于在不重新加载整个页面的情况下，从服务器获取数据并更新网页的某一部分。使用AJAX，你可以创建异步请求，从而提供更快的响应和更好的用户体验。_ajax 获取http数据

Linux图形终端与字符终端-程序员宅基地

文章浏览阅读2.8k次。登录退出、修改密码、关机重启_字符终端

随便推点

Python与Arduino绘制超声波雷达扫描_超声波扫描建模 python库-程序员宅基地

文章浏览阅读3.8k次，点赞3次，收藏51次。前段时间看到一位发烧友制作的超声波雷达扫描神器，用到了Arduino和Processing，可惜啊，我不会Processing更看不懂人家的程序，咋办呢？嘿嘿，所以我就换了个思路解决，因为我会一点Python啊，那就动手吧！在做这个案例之前先要搞明白一个问题：怎么将Arduino通过超声波检测到的距离反馈到Python端？这个嘛，我首先想到了串行通信接口。没错！就是串口。只要Arduino将数据发送给COM口，然后Python能从COM口读取到这个数据就可以啦！我先写了一个测试程序试了一下，OK！搞定_超声波扫描建模 python库

凯撒加密方法介绍及实例说明-程序员宅基地

文章浏览阅读4.2k次。端—端加密指信息由发送端自动加密，并且由TCP/IP进行数据包封装，然后作为不可阅读和不可识别的数据穿过互联网，当这些信息到达目的地，将被自动重组、解密，而成为可读的数据。不可逆加密算法的特征是加密过程中不需要使用密钥，输入明文后由系统直接经过加密算法处理成密文，这种加密后的数据是无法被解密的，只有重新输入明文，并再次经过同样不可逆的加密算法处理，得到相同的加密密文并被系统重新识别后，才能真正解密。2．使用时，加密者查找明文字母表中需要加密的消息中的每一个字母所在位置，并且写下密文字母表中对应的字母。_凯撒加密

工控协议--cip--协议解析基本记录_cip协议embedded_service_error-程序员宅基地

文章浏览阅读5.7k次。CIP报文解析常用到的几个字段：普通类型服务类型:[0x00], CIP对象:[0x02 Message Router], ioi segments:[XX]PCCC（带cmd和func）服务类型:[0x00], CIP对象:[0x02 Message Router], cmd:[0x101], fnc:[0x101]..._cip协议embedded_service_error

如何在vs2019及以后版本(如vs2022)上添加添加ActiveX控件中的MFC类_vs添加mfc库-程序员宅基地

文章浏览阅读2.4k次，点赞9次，收藏13次。有时候我们在MFC项目开发过程中，需要用到一些微软已经提供的功能，如VC++使用EXCEL功能，这时候我们就能直接通过VS2019到如EXCEL.EXE方式，生成对应的OLE头文件，然后直接使用功能，那么，我们上篇文章中介绍了vs2017及以前的版本如何来添加。但由于微软某些方面考虑，这种方式已被放弃。从上图中可以看出，这一功能，在从vs2017版本15.9开始，后续版本已经删除了此功能。那么我们如果仍需要此功能，我们如何在新版本中添加呢。_vs添加mfc库

frame_size (1536) was not respected for a non-last frame_frame_size (1024) was not respected for a non-last-程序员宅基地

文章浏览阅读785次。用ac3编码，执行编码函数时报错入如下：[ac3 @ 0x7fed7800f200] frame_size (1536) was not respected for anon-last frame (avcodec_encode_audio2)用ac3编码时每次送入编码器的音频采样数应该是1536个采样，不然就会报上述错误。这个数字并非刻意固定，而是跟ac3内部的编码算法原理相关。全网找不到，国内音视频之路还有很长的路，音视频人一起加油吧～......_frame_size (1024) was not respected for a non-last frame

Android移动应用开发入门_在安卓移动应用开发中要在活动类文件中声迷你一个复选框变量-程序员宅基地

文章浏览阅读230次，点赞2次，收藏2次。创建Android应用程序一个项目里面可以有很多模块，而每一个模块就对应了一个应用程序。项目结构介绍_在安卓移动应用开发中要在活动类文件中声迷你一个复选框变量