GCD基本使用-02-GCD

//
//  ViewController.m
//  02-GCD基本使用
//
//  Created by mac on 16/4/21.
//  Copyright © 2016年 mac. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    
    //多线程正常开启
    [self asyncConcurrentQueue]; //1. 异步并发
    [self asyncSerialQueue]; //2. 异步串行
    
    //结果都是-主线程在执行
    [self syncConcurrentQueue]; //3. 同步并发
    [self syncSerialQueue];//4. 同步串行
    [self mainQueue]; //5. 主队列
    
    //死锁
    [self syncMainQueue]; //6. 同步主线程
}

/**
 *  async -- 主队列（很常用）
 *  线程之间通信比较常使用
 */
- (void)mainQueue {
    
    //1. 主队列（添加到主队列中的任务，都会自动放到主线程中执行）
    dispatch_queue_t queue = dispatch_get_main_queue();
    
    //2.添加任务到主队列中异步执行
    dispatch_async(queue, ^{
        
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });

}
/**
 *   syncMain 主队列同步（不能用）
 */
- (void)syncMainQueue {
    
    NSLog(@"syncMain=====");
    
    //1. 主队列（添加到主队列中的任务，都会自动放到主线程中执行）
    dispatch_queue_t queue = dispatch_get_main_queue();
    
    //2.添加任务到主队列中同步执行
    dispatch_sync(queue, ^{
        
        //等待中，产生死锁
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });
    
    //互相等待
        NSLog(@"========syncMain=====");
}


/**
 *  async--并发队列（最常用）
 *  会创建线程：同时开多条
 *  任务的执行方式：并发执行
 */
- (void)asyncConcurrentQueue {
    
    //获取并发的全局队列
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    
    //将 任务 添加到 全局队列 中去 异步执行
    dispatch_async(queue, ^{
        
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });
}

/**
 *  async--串行队列（有时候用）
 *  会创建线程：只开一条线程
 *  任务的执行方式：（顺序执行）
 */
- (void)asyncSerialQueue {
    
    //1. 创建一个串行队列
    dispatch_queue_t queue = dispatch_queue_create("随便写", NULL);
    
    //1. 将任务 添加到 串行队列中 去异步执行
    dispatch_async(queue, ^{
        
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_async(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });
}

/**
 *  sync--并发队列
 *  不会创建线程：不开新线程，矛盾了
 *  任务执行方式：串行执行（一个任务执行完，再执行下一个任务）
 */
- (void)syncConcurrentQueue {
    
    //获取并发的全局队列
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    
    //将 任务 添加到全局队列中去 同步执行
    dispatch_sync(queue, ^{
        
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });
}

/**
 *  sync--串行队列（不怎么用）
 *  不会创建线程：不开新线程
 *  任务执行方式：串行执行（一个任务执行完，再执行下一个任务）
 */
- (void)syncSerialQueue {
    
    //1. 创建一个串行队列
    dispatch_queue_t queue = dispatch_queue_create("随便写", NULL);
    
    //将 任务 添加到串行队列中去 同步执行
    dispatch_sync(queue, ^{
        
        NSLog(@"1111==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"2222==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"3333==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"4444==%@", [NSThread currentThread]);
    });
    dispatch_sync(queue, ^{
        
        NSLog(@"5555==%@", [NSThread currentThread]);
    });
}

@end

    //非ARC --需要释放创建的队列
//    dispatch_release(queue);
    
    /**
     *  Foundation:OC
     *  Core Foundation:C
     *  Foundation和Core Foundation框架的数据类型可以互相转换
     */
    NSString *str = @"1234";
    CFStringRef str2 = (__bridge CFStringRef)str;
    NSString *str3 = (__bridge NSString *)str2;
    
    NSLog(@"%@=%@=%@", str, str2, str3);

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