做个爬虫看看豆瓣电影排行的电影的各项信息

合理利用正则表达式，和懂得加个request header 不然网页会拦截。

package zhengze;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.net.URL;
import java.net.MalformedURLException;
import java.net.HttpURLConnection;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.BufferedReader;
class Hello{
private String name;
private static HttpURLConnection connection = null;

public String httpRequest(String url){
String content = "";
try{
URL u = new URL(url);
connection = (HttpURLConnection)u.openConnection();
connection.setRequestMethod("GET");
connection.setRequestProperty("User-Agent","Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36 Edg/90.0.818.56");//connection.setRequestProperty
int code = connection.getResponseCode();
if(code == 200){
InputStream in = connection.getInputStream();
InputStreamReader isr = new InputStreamReader(in,"utf-8");
BufferedReader reader = new BufferedReader(isr);
String line = null;
while((line = reader.readLine()) != null){
content += line;
}
}
}catch(MalformedURLException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}finally{
if(connection != null){
connection.disconnect();
}
}
return content;
}
}

public class Test {
	public static void main(String[] args) {
		
		Hello x=new Hello();
		String fts =  x.httpRequest("https://movie.douban.com/chart");
		//String regex = "<span style=\"font-size:13px;\">(.+?)</span>.+?<p class=.+?>(.+?)</p>.+?<span class=\"rating_nums\">(.+?)</span>"; 
		String regex = "<a class=.+? href=.+?  title=\"(.+?)\">.+? <span style=\"font-size:13px;\">(.+?)</span>.+?<p class=.+?>(.+?)</p>.+?<span class=\"rating_nums\">(.+?)</span>"; 
		Pattern p = Pattern.compile(regex);  
	    Matcher m = p.matcher(fts);  
	    while(m.find())
	    {
	      System.out.println(m.group(1)+" "+m.group(2) +"   "+m.group(4)+ "  :  " +m.group(3));
	      String regex2="<div class=\"pl2\">.+?<a href=\"(.+?)\"  class=\".+?\">";
		    Pattern p2=Pattern.compile(regex2);
		    Matcher m2=p2.matcher(fts);
		    while(m2.find()) {
		    	System.out.println(m2.group(1));
		    	String fts2=x.httpRequest(m2.group(1));
		    	String regex3=" <span class=\"short\">(.+?)</span>";
		    	Pattern p3=Pattern.compile(regex3);
		    	Matcher m3=p3.matcher(fts2);
		    	while(m3.find()) {
		    		System.out.println(m3.group(1));
		    	}
		    }
	      }
	  
	}

}

放个运行截图

是不是很简单。

标签：.+,java,String,Pattern,电影,爬虫,connection,豆瓣,import
来源： https://blog.csdn.net/hhuhgfhggy/article/details/116753566