基於HttpClient實現網路爬蟲~以百度新聞為例
阿新 • • 發佈：2019-01-06
在以前的工作中，實現過簡單的網路爬蟲，沒有系統的介紹過，這篇部落格就係統的介紹以下如何使用java的HttpClient實現網路爬蟲。
關於網路爬蟲的一些理論知識、實現思想以及策略問題，可以參考百度百科“網路爬蟲”，那裡已經介紹的十分詳細，這裡也不再囉嗦，下面就主要介紹如何去實現。
http請求：
程式碼開始之前，還是首先介紹以下如何通過瀏覽器獲取http請求資訊，這一步是分析網站資源的第一步。在瀏覽器介面右鍵有“審查元素”這一功能（如果沒找到，F12一樣可以的），谷歌瀏覽器效果如下：
點選“審查元素”之後會出現如下介面：
其中的Network欄目是做爬蟲應該重點關注的，開啟會看到當前網頁所有的http請求資訊，如下圖：
單擊每個資訊，可以看到http請求的詳細資訊，如下圖所示：
通過程式偽裝成瀏覽器請求的時候，就多需要關注Request Headers裡面的資訊，還有一些需要登入的網站也是需要關注這些的。Response裡面的資訊就是伺服器返回的內容，這裡只做對文字資訊的處理，對圖片、音訊、視訊等資訊不做介紹。
Response裡面就包含這我們爬蟲想獲取的資訊內容。如果裡面的格式不好看的話，可以在瀏覽器中輸入該http請求的url地址，然後右鍵-->檢視網頁原始碼的形式檢視相關資訊。通過分析網頁原始碼中的字串，總結出統一的規則，提取相應的文字資訊。
程式碼實現：
CrawlBase類，模擬http請求的基類
CrawlListPageBase類是CrawlBase的子類，實現了從頁面中獲取連結的URL資訊基類/** *@Description: 獲取網頁資訊基類 */ package com.lulei.crawl; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import org.apache.commons.httpclient.Header; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpException; import org.apache.commons.httpclient.HttpMethod; import org.apache.commons.httpclient.HttpStatus; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.httpclient.methods.PostMethod; import org.apache.log4j.Logger; import com.lulei.util.CharsetUtil; public abstract class CrawlBase { private static Logger log = Logger.getLogger(CrawlBase.class); //連結原始碼 private String pageSourceCode = ""; //返回頭資訊 private Header[] responseHeaders = null; //連線超時時間 private static int connectTimeout = 3500; //連線讀取時間 private static int readTimeout = 3500; //預設最大訪問次數 private static int maxConnectTimes = 3; //網頁預設編碼方式 private static String charsetName = "iso-8859-1"; private static HttpClient httpClient = new HttpClient(); static { httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(connectTimeout); httpClient.getHttpConnectionManager().getParams().setSoTimeout(readTimeout); } /** * @param urlStr * @param charsetName * @param method * @param params * @return * @throws HttpException * @throws IOException * @Author: lulei * @Description: method方式訪問頁面 */ public boolean readPage(String urlStr, String charsetName, String method, HashMap<String, String> params) throws HttpException, IOException { if ("post".equals(method) || "POST".equals(method)) { return readPageByPost(urlStr, charsetName, params); } else { return readPageByGet(urlStr, charsetName, params); } } /** * @param urlStr * @param charsetName * @param params * @return 訪問是否成功 * @throws HttpException * @throws IOException * @Author: lulei * @Description: Get方式訪問頁面 */ public boolean readPageByGet(String urlStr, String charsetName, HashMap<String, String> params) throws HttpException, IOException { GetMethod getMethod = createGetMethod(urlStr, params); return readPage(getMethod, charsetName, urlStr); } /** * @param urlStr * @param charsetName * @param params * @return 訪問是否成功 * @throws HttpException * @throws IOException * @Author: lulei * @Description: Post方式訪問頁面 */ public boolean readPageByPost(String urlStr, String charsetName, HashMap<String, String> params) throws HttpException, IOException{ PostMethod postMethod = createPostMethod(urlStr, params); return readPage(postMethod, charsetName, urlStr); } /** * @param method * @param defaultCharset * @param urlStr * @return 訪問是否成功 * @throws HttpException * @throws IOException * @Author: lulei * @Description: 讀取頁面資訊和頭資訊 */ private boolean readPage(HttpMethod method, String defaultCharset, String urlStr) throws HttpException, IOException{ int n = maxConnectTimes; while (n > 0) { try { if (httpClient.executeMethod(method) != HttpStatus.SC_OK){ log.error("can not connect " + urlStr + "\t" + (maxConnectTimes - n + 1) + "\t" + httpClient.executeMethod(method)); n--; } else { //獲取頭資訊 responseHeaders = method.getResponseHeaders(); //獲取頁面原始碼 InputStream inputStream = method.getResponseBodyAsStream(); BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, charsetName)); StringBuffer stringBuffer = new StringBuffer(); String lineString = null; while ((lineString = bufferedReader.readLine()) != null){ stringBuffer.append(lineString); stringBuffer.append("\n"); } pageSourceCode = stringBuffer.toString(); InputStream in =new ByteArrayInputStream(pageSourceCode.getBytes(charsetName)); String charset = CharsetUtil.getStreamCharset(in, defaultCharset); //下面這個判斷是為了IP歸屬地查詢特意加上去的 if ("Big5".equals(charset)) { charset = "gbk"; } if (!charsetName.toLowerCase().equals(charset.toLowerCase())) { pageSourceCode = new String(pageSourceCode.getBytes(charsetName), charset); } return true; } } catch (Exception e) { e.printStackTrace(); System.out.println(urlStr + " -- can't connect " + (maxConnectTimes - n + 1)); n--; } } return false; } /** * @param urlStr * @param params * @return GetMethod * @Author: lulei * @Description: 設定get請求引數 */ @SuppressWarnings("rawtypes") private GetMethod createGetMethod(String urlStr, HashMap<String, String> params){ GetMethod getMethod = new GetMethod(urlStr); if (params == null){ return getMethod; } Iterator iter = params.entrySet().iterator(); while (iter.hasNext()) { Map.Entry entry = (Map.Entry) iter.next(); String key = (String) entry.getKey(); String val = (String) entry.getValue(); getMethod.setRequestHeader(key, val); } return getMethod; } /** * @param urlStr * @param params * @return PostMethod * @Author: lulei * @Description: 設定post請求引數 */ private PostMethod createPostMethod(String urlStr, HashMap<String, String> params){ PostMethod postMethod = new PostMethod(urlStr); if (params == null){ return postMethod; } Iterator<Entry<String, String>> iter = params.entrySet().iterator(); while (iter.hasNext()) { Map.Entry<String, String> entry = iter.next(); String key = (String) entry.getKey(); String val = (String) entry.getValue(); postMethod.setParameter(key, val); } return postMethod; } /** * @param urlStr * @param charsetName * @return 訪問是否成功 * @throws IOException * @Author: lulei * @Description: 不設定任何頭資訊直接訪問網頁 */ public boolean readPageByGet(String urlStr, String charsetName) throws IOException{ return this.readPageByGet(urlStr, charsetName, null); } /** * @return String * @Author: lulei * @Description: 獲取網頁原始碼 */ public String getPageSourceCode(){ return pageSourceCode; } /** * @return Header[] * @Author: lulei * @Description: 獲取網頁返回頭資訊 */ public Header[] getHeader(){ return responseHeaders; } /** * @param timeout * @Author: lulei * @Description: 設定連線超時時間 */ public void setConnectTimeout(int timeout){ httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(timeout); } /** * @param timeout * @Author: lulei * @Description: 設定讀取超時時間 */ public void setReadTimeout(int timeout){ httpClient.getHttpConnectionManager().getParams().setSoTimeout(timeout); } /** * @param maxConnectTimes * @Author: lulei * @Description: 設定最大訪問次數，連結失敗的情況下使用 */ public static void setMaxConnectTimes(int maxConnectTimes) { CrawlBase.maxConnectTimes = maxConnectTimes; } /** * @param connectTimeout * @param readTimeout * @Author: lulei * @Description: 設定連線超時時間和讀取超時時間 */ public void setTimeout(int connectTimeout, int readTimeout){ setConnectTimeout(connectTimeout); setReadTimeout(readTimeout); } /** * @param charsetName * @Author: lulei * @Description: 設定預設編碼方式 */ public static void setCharsetName(String charsetName) { CrawlBase.charsetName = charsetName; } }
/**
*@Description: 獲取頁面連結地址資訊基類
*/
package com.lulei.crawl;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import com.lulei.util.DoRegex;
public abstract class CrawlListPageBase extends CrawlBase {
private String pageurl;
/**
* @param urlStr
* @param charsetName
* @throws IOException
*/
public CrawlListPageBase(String urlStr, String charsetName) throws IOException{
readPageByGet(urlStr, charsetName);
pageurl = urlStr;
}
/**
* @param urlStr
* @param charsetName
* @param method
* @param params
* @throws IOException
*/
public CrawlListPageBase(String urlStr, String charsetName, String method, HashMap<String, String> params) throws IOException{
readPage(urlStr, charsetName, method, params);
pageurl = urlStr;
}
/**
* @return List<String>
* @Author: lulei
* @Description: 返回頁面上需求的連結地址
*/
public List<String> getPageUrls(){
List<String> pageUrls = new ArrayList<String>();
pageUrls = DoRegex.getArrayList(getPageSourceCode(), getUrlRegexString(), pageurl, getUrlRegexStringNum());
return pageUrls;
}
/**
* @return String
* @Author: lulei
* @Description: 返回頁面上需求的網址連線的正則表示式
*/
public abstract String getUrlRegexString();
/**
* @return int
* @Author: lulei
* @Description: 正則表示式中要去的欄位位置
*/
public abstract int getUrlRegexStringNum();
}
DoRegex類，封裝的一些基於正則表示式字串匹配查詢類
/**
* @Description: 正則處理工具
*/
package com.lulei.util;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class DoRegex {
private static String rootUrlRegex = "(http://.*?/)";
private static String currentUrlRegex = "(http://.*/)";
private static String ChRegex = "([\u4e00-\u9fa5]+)";
/**
* @param dealStr
* @param regexStr
* @param splitStr
* @param n
* @return String
* @Author: lulei
* @Description: 正則匹配結果，每條記錄用splitStr分割
*/
public static String getString(String dealStr, String regexStr, String splitStr, int n){
String reStr = "";
if (dealStr == null || regexStr == null || n < 1 || dealStr.isEmpty()){
return reStr;
}
splitStr = (splitStr == null) ? "" : splitStr;
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
StringBuffer stringBuffer = new StringBuffer();
while (matcher.find()) {
stringBuffer.append(matcher.group(n).trim());
stringBuffer.append(splitStr);
}
reStr = stringBuffer.toString();
if (splitStr != "" && reStr.endsWith(splitStr)){
reStr = reStr.substring(0, reStr.length() - splitStr.length());
}
return reStr;
}
/**
* @param dealStr
* @param regexStr
* @param n
* @return String
* @Author: lulei
* @Description: 正則匹配結果，將所有匹配記錄組裝成字串
*/
public static String getString(String dealStr, String regexStr, int n){
return getString(dealStr, regexStr, null, n);
}
/**
* @param dealStr
* @param regexStr
* @param n
* @return String
* @Author: lulei
* @Description: 正則匹配第一條結果
*/
public static String getFirstString(String dealStr, String regexStr, int n){
if (dealStr == null || regexStr == null || n < 1 || dealStr.isEmpty()){
return "";
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
return matcher.group(n).trim();
}
return "";
}
/**
* @param dealStr
* @param regexStr
* @param n
* @return ArrayList<String>
* @Author: lulei
* @Description: 正則匹配結果，將匹配結果組裝成陣列
*/
public static List<String> getList(String dealStr, String regexStr, int n){
List<String> reArrayList = new ArrayList<String>();
if (dealStr == null || regexStr == null || n < 1 || dealStr.isEmpty()){
return reArrayList;
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
reArrayList.add(matcher.group(n).trim());
}
return reArrayList;
}
/**
* @param url
* @param currentUrl
* @return String
* @Author: lulei
* @Description: 組裝網址，網頁的url
*/
private static String getHttpUrl(String url, String currentUrl){
try {
url = encodeUrlCh(url);
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (url.indexOf("http") == 0){
return url;
}
if (url.indexOf("/") == 0){
return getFirstString(currentUrl, rootUrlRegex, 1) + url.substring(1);
}
return getFirstString(currentUrl, currentUrlRegex, 1) + url;
}
/**
* @param dealStr
* @param regexStr
* @param currentUrl
* @param n
* @return ArrayList<String>
* @Author: lulei
* @Description: 獲取和正則匹配的絕對連結地址
*/
public static List<String> getArrayList(String dealStr, String regexStr, String currentUrl, int n){
List<String> reArrayList = new ArrayList<String>();
if (dealStr == null || regexStr == null || n < 1 || dealStr.isEmpty()){
return reArrayList;
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
reArrayList.add(getHttpUrl(matcher.group(n).trim(), currentUrl));
}
return reArrayList;
}
/**
* @param url
* @return
* @throws UnsupportedEncodingException
* @Author: lulei
* @Description: 將連線地址中的中文進行編碼處理
*/
public static String encodeUrlCh (String url) throws UnsupportedEncodingException {
while (true) {
String s = getFirstString(url, ChRegex, 1);
if ("".equals(s)){
return url;
}
url = url.replaceAll(s, URLEncoder.encode(s, "utf-8"));
}
}
/**
* @param dealStr
* @param regexStr
* @param array 正則位置陣列
* @return
* @Author:lulei
* @Description: 獲取全部
*/
public static List<String[]> getListArray(String dealStr, String regexStr, int[] array) {
List<String[]> reArrayList = new ArrayList<String[]>();
if (dealStr == null || regexStr == null || array == null) {
return reArrayList;
}
for (int i = 0; i < array.length; i++) {
if (array[i] < 1) {
return reArrayList;
}
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
String[] ss = new String[array.length];
for (int i = 0; i < array.length; i++) {
ss[i] = matcher.group(array[i]).trim();
}
reArrayList.add(ss);
}
return reArrayList;
}
/**
* @param dealStr
* @param regexStr
* @param array
* @return
* @Author:lulei
* @Description: 獲取全部
*/
public static List<String> getStringArray(String dealStr, String regexStr, int[] array) {
List<String> reStringList = new ArrayList<String>();
if (dealStr == null || regexStr == null || array == null) {
return reStringList;
}
for (int i = 0; i < array.length; i++) {
if (array[i] < 1) {
return reStringList;
}
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < array.length; i++) {
sb.append(matcher.group(array[i]).trim());
}
reStringList.add(sb.toString());
}
return reStringList;
}
/**
* @param dealStr
* @param regexStr
* @param array 正則位置陣列
* @return
* @Author:lulei
* @Description: 獲取第一個
*/
public static String[] getFirstArray(String dealStr, String regexStr, int[] array) {
if (dealStr == null || regexStr == null || array == null) {
return null;
}
for (int i = 0; i < array.length; i++) {
if (array[i] < 1) {
return null;
}
}
Pattern pattern = Pattern.compile(regexStr, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher matcher = pattern.matcher(dealStr);
while (matcher.find()) {
String[] ss = new String[array.length];
for (int i = 0; i < array.length; i++) {
ss[i] = matcher.group(array[i]).trim();
}
return ss;
}
return null;
}
}
CharsetUtil類，編碼方式檢測類
/**
*@Description: 編碼方式檢測類
*/
package com.lulei.util;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.nio.charset.Charset;
import info.monitorenter.cpdetector.io.ASCIIDetector;
import info.monitorenter.cpdetector.io.CodepageDetectorProxy;
import info.monitorenter.cpdetector.io.JChardetFacade;
import info.monitorenter.cpdetector.io.ParsingDetector;
import info.monitorenter.cpdetector.io.UnicodeDetector;
public class CharsetUtil {
private static final CodepageDetectorProxy detector;
static {//初始化探測器
detector = CodepageDetectorProxy.getInstance();
detector.add(new ParsingDetector(false));
detector.add(ASCIIDetector.getInstance());
detector.add(UnicodeDetector.getInstance());
detector.add(JChardetFacade.getInstance());
}
/**
* @param url
* @param defaultCharset
* @Author:lulei
* @return 獲取檔案的編碼方式
*/
public static String getStreamCharset (URL url, String defaultCharset) {
if (url == null) {
return defaultCharset;
}
try {
//使用第三方jar包檢測檔案的編碼
Charset charset = detector.detectCodepage(url);
if (charset != null) {
return charset.name();
}
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return defaultCharset;
}
/**
* @param inputStream
* @param defaultCharset
* @return
* @Author:lulei
* @Description: 獲取檔案流的編碼方式
*/
public static String getStreamCharset (InputStream inputStream, String defaultCharset) {
if (inputStream == null) {
return defaultCharset;
}
int count = 200;
try {
count = inputStream.available();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
//使用第三方jar包檢測檔案的編碼
Charset charset = detector.detectCodepage(inputStream, count);
if (charset != null) {
return charset.name();
}
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return defaultCharset;
}
}
百度新聞案例：
1）找到百度新聞更新列表頁，如http://news.baidu.com/n?cmd=4&class=civilnews&pn=1&from=tab 介面如下圖所示：
文章URL連結地址如下圖所示：
通過對原始檔的分析，編寫BaiduNewList類，實現百度新聞列表頁資訊的抓取，程式碼如下：
/**
*@Description: 百度新聞滾動列表頁，可以獲取當前頁面上的連結
*/
package com.lulei.crawl.news;
import java.io.IOException;
import java.util.HashMap;
import com.lulei.crawl.CrawlListPageBase;
public class BaiduNewList extends CrawlListPageBase{
private static HashMap<String, String> params;
/**
* 新增相關頭資訊，對請求進行偽裝
*/
static {
params = new HashMap<String, String>();
params.put("Referer", "http://www.baidu.com");
params.put("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.125 Safari/537.36");
}
public BaiduNewList(String urlStr) throws IOException {
super(urlStr, "utf-8", "get", params);
}
@Override
public String getUrlRegexString() {
// TODO Auto-generated method stub
//新聞列表頁中文章連結地址的正則表示式
return "• <a href=\"(.*?)\"";
}
@Override
public int getUrlRegexStringNum() {
// TODO Auto-generated method stub
//連結地址在正則表示式中的位置
return 1;
}
/**
* @param args
* @throws IOException
* @Author:lulei
* @Description: 測試用例
*/
public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
BaiduNewList baidu = new BaiduNewList("http://news.baidu.com/n?cmd=4&class=sportnews&pn=1&from=tab");
for (String s : baidu.getPageUrls()) {
System.out.println(s);
}
}
}
2）通過第一步獲取的URL，得到新聞所在的內容頁面URL，由於百度新聞列表頁面上的新聞來自不同的站，所以很難找到一個通用的結構，大多數的新聞類網站，內容都是放在p標籤內，所以就採用瞭如下的方式獲取新聞的內容，如下圖：
News類具體實現如下所示：
/**
*@Description: 新聞類網站新聞內容
*/
package com.lulei.crawl.news;
import java.io.IOException;
import java.util.HashMap;
import org.apache.commons.httpclient.HttpException;
import com.lulei.crawl.CrawlBase;
import com.lulei.util.DoRegex;
public class News extends CrawlBase{
private String url;
private String content;
private String title;
private String type;
private static String contentRegex = "<p.*?>(.*?)</p>";
private static String titleRegex = "<title>(.*?)</title>";
private static int maxLength = 300;
private static HashMap<String, String> params;
/**
* 新增相關頭資訊，對請求進行偽裝
*/
static {
params = new HashMap<String, String>();
params.put("Referer", "http://www.baidu.com");
params.put("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.125 Safari/537.36");
}
/**
* @Author:lulei
* @Description: 預設p標籤內的內容為正文，如果正文長度查過設定的最大長度，則擷取前半部分
*/
private void setContent() {
String content = DoRegex.getString(getPageSourceCode(), contentRegex, 1);
content = content.replaceAll("\n", "")
.replaceAll("<script.*?/script>", "")
.replaceAll("<style.*?/style>", "")
.replaceAll("<.*?>", "");
this.content = content.length() > maxLength ? content.substring(0, maxLength) : content;
}
/**
* @Author:lulei
* @Description: 預設title標籤內的內容為標題
*/
private void setTitle() {
this.title = DoRegex.getString(getPageSourceCode(), titleRegex, 1);;
}
public News(String url) throws HttpException, IOException {
this.url = url;
readPageByGet(url, "utf-8", params);
setContent();
setTitle();
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String getContent() {
return content;
}
public String getTitle() {
return title;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public static void setMaxLength(int maxLength) {
News.maxLength = maxLength;
}
/**
* @param args
* @throws HttpException
* @throws IOException
* @Author:lulei
* @Description: 測試用例
*/
public static void main(String[] args) throws HttpException, IOException {
// TODO Auto-generated method stub
News news = new News("http://we.sportscn.com/viewnews-1634777.html");
System.out.println(news.getContent());
System.out.println(news.getTitle());
}
}
3）編寫抓取的入口，這裡為了簡單，只做了兩層的分析，所以新聞更新列表也的URL就直接寫在程式中。如下圖所示：
執行一次採集任務如下圖所示：
在main函式裡面只需要一次性或週期性的去執行run函式即可，具體程式碼如下：
/**
*@Description:
*/
package com.lulei.knn.data;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import com.lulei.crawl.news.BaiduNewList;
import com.lulei.crawl.news.News;
import com.lulei.knn.index.KnnIndex;
import com.lulei.knn.index.KnnSearch;
import com.lulei.util.ParseMD5;
public class CrawlNews {
private static List<Info> infos;
private static KnnIndex knnIndex = new KnnIndex();
private static KnnSearch knnSearch = new KnnSearch();
private static HashMap<String, Integer> result;
static {
infos = new ArrayList<Info>();
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=sportnews&pn=1&from=tab", "體育類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=sportnews&pn=2&from=tab", "體育類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=sportnews&pn=3&from=tab", "體育類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=mil&pn=1&sub=0", "軍事類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=mil&pn=2&sub=0", "軍事類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=mil&pn=3&sub=0", "軍事類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=finannews&pn=1&sub=0", "財經類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=finannews&pn=2&sub=0", "財經類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=finannews&pn=3&sub=0", "財經類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=internet&pn=1&from=tab", "網際網路"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=housenews&pn=1&sub=0", "房產類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=housenews&pn=2&sub=0", "房產類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=housenews&pn=3&sub=0", "房產類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=gamenews&pn=1&sub=0", "遊戲類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=gamenews&pn=2&sub=0", "遊戲類"));
infos.add(new Info("http://news.baidu.com/n?cmd=4&class=gamenews&pn=3&sub=0", "遊戲類"));
}
/**
*@Description: 抓取網址資訊
*@Author:lulei
*/
static class Info{
String url;
String type;
Info(String url, String type) {
this.url = url;
this.type = type;
}
}
/**
* @param info
* @Author:lulei
* @Description: 抓取一個列表頁面下的新聞資訊
*/
private void crawl(Info info) {
if (info == null) {
return;
}
try {
BaiduNewList baiduNewList = new BaiduNewList(info.url);
List<String> urls = baiduNewList.getPageUrls();
for (String url : urls) {
News news = new News(url);
NewsBean newBean = new NewsBean();
newBean.setId(ParseMD5.parseStrToMd5L32(url));
newBean.setType(info.type);
newBean.setUrl(url);
newBean.setTitle(news.getTitle());
newBean.setContent(news.getContent());
//儲存到索引檔案中
knnIndex.add(newBean);
//knn驗證
if (news.getContent() == null || "".equals(news.getContent())) {
result.put("E", 1+result.get("E"));
continue;
}
if (info.type.equals(knnSearch.getType(news.getContent()))) {
result.put("R", 1+result.get("R"));
} else {
result.put("W", 1+result.get("W"));
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* @Author:lulei
* @Description: 啟動入口
*/
public void run() {
result = new HashMap<String, Integer>();
result.put("R", 0);
result.put("W", 0);
result.put("E", 0);
for (Info info : infos) {
System.out.println(info.url + "------start");
crawl(info);
System.out.println(info.url + "------end");
}
try {
knnIndex.commit();
System.out.println("R = " + result.get("R"));
System.out.println("W = " + result.get("W"));
System.out.println("E = " + result.get("E"));
System.out.println("精確度：" + (result.get("R") * 1.0 / (result.get("R") + result.get("W"))));
System.out.println("-------------finished---------------");
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
new CrawlNews().run();
}
}