自己写的Java抓图程序（用了BloomFilter算法）

package com.hengking.crawl; import java.text.SimpleDateFormat; import java.util.*; import java.net.*; import java.awt.image.BufferedImage; import java.io.*; import java.util.regex.*; import javax.imageio.ImageIO; import com.hengking.crawl.util.UtilSeriz; // 搜索Web爬行者 public class SearchCrawler implements Runnable{ /* disallowListCache缓存robot不允许搜索的URL。 Robot协议在Web站点的根目录下设置一个robots.txt文件, *规定站点上的哪些页面是限制搜索的。 搜索程序应该在搜索过程中跳过这些区域,下面是robots.txt的一个例子: # robots.txt for http://somehost.com/ User-agent: * Disallow: /cgi-bin/ Disallow: /registration # /Disallow robots on registration page Disallow: /login */ public static SimpleBloomFilter filterUrl; public static SimpleBloomFilter filterImg; private HashMap< String,ArrayList< String>> disallowListCache = new HashMap< String,ArrayList< String>>(); ArrayList< String> errorList= new ArrayList< String>();//错误信息 ArrayList< String> result=new ArrayList< String>(); //搜索到的结果 String startUrl;//开始搜索的起点 int maxUrl;//最大处理的url数 String searchString;//要搜索的字符串(英文) boolean caseSensitive=false;//是否区分大小写 boolean limitHost=false;//是否在限制的主机内搜索 private static String outdir; private static String seroutdir; private static String seroutdirimg; private boolean blnFlag=false; /*** * 构造函数 * @param startUrl * @param maxUrl * @param searchString */ public SearchCrawler(String startUrl,int maxUrl,String searchString) { this.startUrl=startUrl; this.maxUrl=maxUrl; this.searchString=searchString; } public ArrayList< String> getResult(){ return result; } public void run(){//启动搜索线程 new Thread(new TimeWrite2File()).start(); blnFlag=true; crawl(startUrl,maxUrl, searchString,limitHost,caseSensitive); } //检测URL格式 private URL verifyUrl(String url) { // 只处理HTTP URLs. if (!url.toLowerCase().startsWith("http://")) return null; URL verifiedUrl = null; try { verifiedUrl = new URL(url); } catch (Exception e) { return null; } return verifiedUrl; } // 检测robot是否允许访问给出的URL. private boolean isRobotAllowed(URL urlToCheck) { String host = urlToCheck.getHost().toLowerCase();//获取给出RUL的主机 //System.out.println("主机="+host); // 获取主机不允许搜索的URL缓存 ArrayList< String> disallowList =disallowListCache.get(host); // 如果还没有缓存,下载并缓存。 if (disallowList == null) { disallowList = new ArrayList< String>(); try { URL robotsFileUrl =new URL("http://" + host + "/robots.txt"); BufferedReader reader =new BufferedReader(new InputStreamReader(robotsFileUrl.openStream())); // 读robot文件，创建不允许访问的路径列表。 String line; while ((line = reader.readLine()) != null) { if (line.indexOf("Disallow:") == 0) {//是否包含"Disallow:" String disallowPath =line.substring("Disallow:".length());//获取不允许访问路径 // 检查是否有注释。 int commentIndex = disallowPath.indexOf("#"); if (commentIndex != - 1) { disallowPath =disallowPath.substring(0, commentIndex);//去掉注释 } disallowPath = disallowPath.trim(); disallowList.add(disallowPath); } } // 缓存此主机不允许访问的路径。 disallowListCache.put(host, disallowList); } catch (Exception e) { return true; //web站点根目录下没有robots.txt文件,返回真 } } String file = urlToCheck.getFile(); //System.out.println("文件getFile()="+file); for (int i = 0; i < disallowList.size(); i++) { String disallow = disallowList.get(i); if (file.startsWith(disallow)) { return false; } } return true; } private String downloadPage(URL pageUrl) { try { // Open connection to URL for reading. BufferedReader reader = new BufferedReader(new InputStreamReader(pageUrl.openStream())); // Read page into buffer. String line; StringBuffer pageBuffer = new StringBuffer(); while ((line = reader.readLine()) != null) { pageBuffer.append(line); } return pageBuffer.toString(); } catch (Exception e) { } return null; } // 从URL中去掉"www" private String removeWwwFromUrl(String url) { int index = url.indexOf("://www."); if (index != -1) { return url.substring(0, index + 3) + url.substring(index + 7); } return (url); } // 解析页面并找出链接 private ArrayList< String> retrieveLinks(URL pageUrl, String pageContents, boolean limitHost) { // 用正则表达式编译链接的匹配模式。 Pattern p =Pattern.compile("<a\\s+href\\s*=\\s*\"?(.*?)[\"|>]",Pattern.CASE_INSENSITIVE); Matcher m = p.matcher(pageContents); ArrayList< String> linkList = new ArrayList< String>(); while (m.find()) { String link = m.group(1).trim(); if (link.length() < 1) { continue; } // 跳过链到本页面内链接。 if (link.charAt(0) == '#') { continue; } if (link.indexOf("mailto:") != -1) { continue; } if (link.toLowerCase().indexOf("javascript") != -1) { continue; } if (link.indexOf("://") == -1){ if (link.charAt(0) == '/') {//处理绝对地 link = "http://" + pageUrl.getHost()+":"+pageUrl.getPort()+ link; } else { String file = pageUrl.getFile(); if (file.indexOf('/') == -1) {//处理相对地址 link = "http://" + pageUrl.getHost()+":"+pageUrl.getPort() + "/" + link; } else { String path =file.substring(0, file.lastIndexOf('/') + 1); link = "http://" + pageUrl.getHost() +":"+pageUrl.getPort()+ path + link; } } } int index = link.indexOf('#'); if (index != -1) { link = link.substring(0, index); } link = removeWwwFromUrl(link); URL verifiedLink = verifyUrl(link); if (verifiedLink == null) { continue; } /* 如果限定主机，排除那些不合条件的URL*/ if (limitHost && !pageUrl.getHost().toLowerCase().equals( verifiedLink.getHost().toLowerCase())) { continue; } // 跳过那些已经处理的链接. // if (crawledList.contains(link)) { // continue; // } if(filterUrl.contains(link)) { continue; } else { filterUrl.add(link); } linkList.add(link); } return (linkList); } // 解析页面并找出链接 private ArrayList< String> retrieveImgLinks(URL pageUrl, String pageContents, boolean limitHost) { // 用正则表达式编译链接的匹配模式。 Pattern p =Pattern.compile("<img\\s+src\\s*=\\s*\"?(.*?)[\"|>]",Pattern.CASE_INSENSITIVE); Matcher m = p.matcher(pageContents); ArrayList< String> linkList = new ArrayList< String>(); while (m.find()) { String link = m.group(1).trim(); if (link.length() < 1) { continue; } // 跳过链到本页面内链接。 if (link.charAt(0) == '#') { continue; } if (link.indexOf("mailto:") != -1) { continue; } if (link.toLowerCase().indexOf("javascript") != -1) { continue; } if (link.indexOf("://") == -1) { if (link.char