【java】使用URL和CookieManager爬取页面的验证码和cookie并保存

使用java的net包和io包下的几个工具爬取页面的验证码图片并保存到本地。

然后可以把获取的cookie保存下来，做进一步处理。比如通过识别验证码，进一步使用验证码和用户名，密码，保存下来的cookie提交表单验证。使用java模拟登录功能

package com.carl.carlapp.test;

import java.io.FileOutputStream;
import java.io.InputStream;
import java.net.CookieHandler;
import java.net.CookieManager;
import java.net.CookieStore;
import java.net.HttpCookie;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.Date;
import java.util.List;

/** 
 * @author 作者 Carl Zhang. E-mail: carlzhangweiwen@sina.com
 * @version 创建时间：2016年3月2日 下午10:39:52 
 * 类说明 
 */
public class CookieTest {
     public static void main(String args[]) throws Exception {
//            String urlString = "http://58.215.195.18:10010/login_person.jsp";
             String urlString = "http://58.215.195.18:10010/jcaptcha?date="+ new Date().getTime();         
            
            CookieManager manager = new CookieManager();
            CookieHandler.setDefault(manager);
            URL url = new URL(urlString);   
            HttpURLConnection httpConn = (HttpURLConnection) url.openConnection(); 
            
            //将得到的验证码保存下来
            saveFile(httpConn, "E:\tset33.jpg");
            
//            Object content = httpConn.getContent();
//            String contentType = httpConn.getContentType();
//            System.out.println(contentType);//MIME type:text/html
            
            //因为http已经做了请求，所以会得到cookie
            CookieStore cookieJar = manager.getCookieStore();
            List<HttpCookie> cookies = cookieJar.getCookies();
            for (HttpCookie cookie : cookies) {
              System.out.println(cookie);
            }
          }
     public static void saveFile(URLConnection conn,String fullPath){
         saveFile(conn, fullPath, 8);
     }
     /**
      * 讲文件保存下来
      * @param conn URLConnection连接
      * @param fullPath 文件路径及文件名
      * @param length 每次读文件字节数
      */
     public static void saveFile(URLConnection conn, String fullPath, int length){
            try {
                if(conn == null){
                    throw new Exception("Can't get URLConnection.");
                }
                InputStream is = conn.getInputStream();
                FileOutputStream fos = new FileOutputStream(fullPath);
                byte[] b = new byte[length];
                int len = 0;
                while((len = is.read(b)) != -1){
                    fos.write(b,0,len); 
                }
                fos.flush();
                fos.close();
                is.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

}

打印结果：

BIGipServerweb_server=202025152.36895.0000
JSESSIONID=1D61F297617400C594B3F75E3C76D27F