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Java爬取先知论坛文章

0x00 前言

上篇文章写了部分爬虫代码，这里给出一个完整的爬取先知论坛文章代码，用于技术交流。

0x01 代码实现

pom.xml加入依赖:

<dependencies>

        <!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.3</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.jsoup/jsoup -->
        <dependency>
            <groupId>org.jsoup</groupId>
            <artifactId>jsoup</artifactId>
            <version>1.11.3</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.4</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.7</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/junit/junit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>





    </dependencies>

实现代码

实现类：

package xianzhi;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.select.Elements;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;
import java.util.List;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class Climbimpl implements Runnable {
    private String url ;
    private int pages;
    private String filename;



    Lock lock = new ReentrantLock();

    public Climbimpl(String url, int pages,String filename) {
        this.url = url;
        this.pages = pages;
        this.filename = filename;
    }

    public void run() {
        File file = new File(this.filename);

        boolean mkdir = file.mkdir();

        if (mkdir){
            System.out.println("目录已创建");
        }

        lock.lock();

//        String url = "https://xz.aliyun.com/";

        for (int i = 1; i < this.pages; i++) {
            try {

            String requesturl = this.url+"?page="+i;
            Document doc = null;
            doc = Jsoup.parse(new URL(requesturl), 10000);
            Elements element = doc.getElementsByClass("topic-title");
            List<String> href = element.eachAttr("href");
                for (String s : href) {
                    try{
                        Document requests = Jsoup.parse(new URL(this.url+s), 100000);
//                        String topic_content = requests.getElementById("topic_content").text();
                        String titile = requests.getElementsByClass("content-title").first().text();
                        System.out.println("已爬取"+titile+"->"+this.filename+titile+".html");


                        BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(new FileOutputStream(this.filename+titile+".html"));
                        bufferedOutputStream.write(requests.toString().getBytes());
                        bufferedOutputStream.flush();
                        bufferedOutputStream.close();


                    }catch (Exception e){
                        System.out.println("爬取"+this.url+s+"报错"+"报错信息"+e);
                    }
                }


            } catch (IOException e) {
                e.printStackTrace();
            }


        }
        lock.unlock();

    }
}

main类：

package xianzhi;

public class TestClimb {
    public static void main(String[] args) {
        int Threadlist_num = 10; //线程数
        String url = "https://xz.aliyun.com/";  //设置url
        int pages = 10; //读取页数
        String path = "D:\\paramss\\";  //设置保存路径

        Climbimpl climbimpl = new Climbimpl(url,pages,path);
        for (int i = 0; i < Threadlist_num; i++) {
            new Thread(climbimpl).start();

        }
    }
}

0x03 结尾

该爬虫总体的代码都比较简单。