请求的地址为:

http://api.map.baidu.com/place/v2/search?&q=%E9%A5%AD%E5%BA%97&region=%E9%87%8D%E5%BA%86&output=json&ak=10f2c8e6b9af4244be2453001b9dfe76&page_size=20&page_num=5

page_num 需要每次+1 来获取参数

考虑到获取的速度问题,决定每个请求都创建一个线程放入线程池,代码如下

//

package threadpool;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class test {
public static void main(String[] args) {
ExecutorService pool = Executors.newFixedThreadPool(3);
int i = 1;
while(i<=4){
　　//4次http请求
　　pool.execute(new loadData(i));
　　i++;
　　}
　　}
}

//抓取数据的类,实现runable

package threadpool;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class loadData implements Runnable {
     StringBuilder temp = new StringBuilder();
     int pagenumber;
     public loadData(int i){
       this.pagenumber = i;
     }
@Override
    public void run() {
          System.out.println(pagenumber);
          try {
              String address = "http://api.map.baidu.com/place/v2/search?                                    &q=%E9%A5%AD%E5%BA%97&region=%E9%87%8D%E5%BA%86&output=json&ak=10f2c8e6b9af4244be2453001b9dfe76&page_size=20&page_num="+pagenumber;
             URL url=new URL(address);
             HttpURLConnection Connection= (HttpURLConnection) url.openConnection();
             InputStream is = Connection.getInputStream();
             int len = 0; //每次读取的实际字节数
             byte[] temp = new byte[1024]; //1024每次读取的字符的长度
             StringBuilder sb = new StringBuilder();
            //new String 的参数byte,offset,len
            while((len=is.read(temp))!=-1){
               sb.append(new String(temp,0,len));   //最后一次的长度不一定为1024
            }
               is.close();
            } catch (MalformedURLException e) {
               // TODO Auto-generated catch block
              e.printStackTrace();
           } catch (IOException e) {
           // TODO Auto-generated catch block
            e.printStackTrace();
        }
      }
}