Java 爬虫多线程

    4.0.0

    
        spring-boot-starter-parent
        org.springframework.boot
        2.0.1.RELEASE
        
    
    org.example
    mySpider
    1.0-SNAPSHOT

    
        
            org.springframework.boot
            spring-boot-starter-web
            2.4.2
        
        
            com.alibaba
            druid-spring-boot-starter
            1.2.4
        
        
            org.springframework.boot
            spring-boot-starter-test
            2.4.2
            test
        
        
            mysql
            mysql-connector-java
            8.0.22
        
        
            com.alibaba
            fastjson
            1.2.73
        
        
            com.google.guava
            guava
            22.0
        
        
            org.jsoup
            jsoup
            1.14.2
        
        
            org.apache.commons
            commons-lang3
            3.9
        
        
        
            com.baomidou
            mybatis-plus-boot-starter
            3.4.1
        
        
            com.baomidou
            mybatis-plus-generator
            3.4.1
        
        
        
            org.freemarker
            freemarker
            2.3.28
        

        
            org.projectlombok
            lombok
            1.18.8
        
        
            org.apache.httpcomponents
            httpclient
            4.5.4
        

        
            org.springframework.boot
            spring-boot-starter-data-redis
        
        
            junit
            junit
            4.12
            test
        
    

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/spider?useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver
    username: root
    password: root
    dbcp2:
      min-idle: 5
      initial-size: 5
      max-total: 5
      max-wait-millis: 100
  redis:
    database: 0
    host: 127.0.0.1
    port: 6379
    password: 123456

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for goods_info
-- ----------------------------
DROP TABLE IF EXISTS `goods_info`;
CREATE TABLE `goods_info`  (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `goods_id` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `goods_name` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin NULL DEFAULT NULL,
  `goods_price` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin NULL DEFAULT NULL,
  `img_url` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8 COLLATE = utf8_bin ROW_FORMAT = Dynamic;

SET FOREIGN_KEY_CHECKS = 1;

1.SpringBoot
2.SpringMVC
3.HttpClinet
4.Jsoup
5.多线程（线程池）
6.redis
7.mysql（mybatis-plus）

1.启动类进行启动，开启 @PostConstruct，调用spiderHandle

2.spiderHandle
在spiderHandle中，使用线程池处理任务，线程池工厂和拒绝策略由自己确定；同时引入countDownLatch进行线程同步，使主线程等待线程池的所有任务结束，便于计时。

3.SpiderService处理爬取数据，进行解析，同时批量插入到数据库中.注意：因为是多线程成爬取，如果爬取的数据需要存入集合，需要采用并发安全的List,这里使用了synchronized锁

4.GoodsInfoMapper
是使用mybatis-plus生成得到

5.Redis队列
因为在爬取的时候可能因为网络等原因，爬取的那一条数据会失败。因此，将爬取的页码放入到redis中。

redisTemplate.opsForList().leftPush("page",parms.get("page"));

我在后台重新启动一个线程，自旋的形式将Redis的队列中的数据阻塞式取出。然后再一次爬取。

  for (int i = 1; i < 201; i += 2) {
            Map params = new HashMap<>();
            params.put("keyword", "零食");
            params.put("enc", "utf-8");
            params.put("wc", "零食");
            params.put("page", i + "");
            threadPoolExecutor.execute(() -> {
                goodsInfoService.spiderData(SysConstant.BASE_URL, params);
                countDownLatch.countDown();
            });
        }

源代码在本人github上：多线程爬虫