parser.java

人工智能作业 人工智能作业

//package firstproject;

import java.io.*;
import java.net.*;

public class Parser {

  String[] urllist; //saving the parser's result
  String[] urlnamelist;
  String str;
  String str_encode;
  String keywordlist;
  String str_head;
  String str_tail;
  String str_end;
  int count;
  int downcount;
  /*Baiduparser(){
    urllist = new String[1000];
    str = new String();
    str_encode = new String();
    keywordlist = new String("ITNLP");
    str_head = new String("<a href=\""); //if string contains " there should be a \before it
    str_tail = new String("\">");
    count = 0;
    downcount=1000;


  }*/
  Parser(int a){
   urllist = new String[100];
   urlnamelist = new String[100];
   str = new String();
   str_encode = new String();
   keywordlist = new String("ITNLP");
   str_head = new String("<a accesskey="); //if string contains " there should be a \before it
   str_tail = new String("\">");
   str_end = new String("</a>");
   count = 0;
   downcount=a; //The number of urls which are requested

  }
  public String printurl(int i){
  	
      return this.urllist[i]+'\n';
  }
  public void setkeyword(String strlist) {
    keywordlist = strlist;
  }


  public void parse() {
	try{
 	str_encode = URLEncoder.encode(keywordlist, "UTF-8");
 	}
 	catch(UnsupportedEncodingException ex){
 		throw new RuntimeException("Broken VM does not support UTF-8");
 	}
//	str_encode = keywordlist;
//    System.out.println(str_encode);
    for(int i=0;i<downcount/5+1;i++)
    {
      count=0;
      String str_temp = String.valueOf(i*5);
    try {
      URL url = new URL("http://www.google.cn/m/search?mrestrict=wml&site=mobile&q=" + str_encode + "&start=" + str_temp + "&sa=N"); 
      // Read all the text returned by the server
      BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));

      while ( (str = in.readLine()) != null && count < 5) {
      	
      	System.out.println(str);
      	int pos2 = 0; //point to the str_tail
      	while(pos2 < str.length() && count < 5){
      		
	      	while(!str.startsWith(str_tail,pos2) && pos2 < str.length()){
				pos2++;
			}
			if(pos2 == str.length()){
				pos2 = 0;
				break;
			}
			int pos1 = pos2; //pos1 points to the str_head
			while(!str.startsWith(str_head,pos1) && pos1 >= 0){
				pos1--;
			}
			if(pos1 < 0){
				pos2++;
				continue;
			}
			int pos3 = pos2;
			while(!str.startsWith(str_end,pos3) && pos3 < str.length()){
				pos3++;
			}
			if(pos3 == str.length()){
				pos2 = 0;
				break;
			}
	        urllist[count+5*i] = str.substring(pos1+str_head.length()+10, pos2);
	        urlnamelist[count+5*i] = str.substring(pos2+str_tail.length(),pos3);
	        count++;
	        pos2++;
      	}
      }
      in.close();
    }
    catch (MalformedURLException q) {
    }
    catch (IOException w) {
    }

  }
}
}