【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