package com.fh.util;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* 說明:爬取網頁
* 作者:FH Admin
* from:fhadmin.cn
*/
public class GetWeb {
/**
* 獲取當前網頁的code
*
* @param httpUrl
* 網頁地址
* @return
* @throws IOException
*/
public static String getHtmlCode(String httpUrl) throws IOException {
String content = ""; // 定義字符串content
URL url = new URL(httpUrl); // 生成傳入的URL的對象
BufferedReader reader = new BufferedReader(new InputStreamReader(
url.openStream(), "utf-8"));// 獲得當前url的字節流(緩衝)
String input;
while ((input = reader.readLine()) != null) { // 當前行存在數據時
content += input; // 將讀取數據賦給content
}
reader.close(); // 關閉緩衝區
return content;
}
/**
* 把網頁中的所有圖片的完整路徑放到list裏面
*
* @param wwwurl
* 要爬的網頁連接
* @throws IOException
*/
public static List<String> getImagePathList(String httpUrl)
throws IOException {
// 通過擴展名匹配網頁圖片的正則表達式
// String searchImgReg =
// "(?x)(src|SRC|background|BACKGROUND)=('|\")/?(([\\w-]+/)*([\\w-]+\\.(jpg|JPG|png|PNG|gif|GIF)))('|\")";
// String searchImgReg2 =
// "(?x)(src|SRC|background|BACKGROUND)=('|\")(http://([\\w-]+\\.)+[\\w-]+(:[0-9]+)*(/[\\w-]+)*(/[\\w-]+\\.(jpg|JPG|png|PNG|gif|GIF)))('|\")";
// 通過img標籤匹配網頁圖片的正則表達式
String searchImgReg = "<(img|IMG)\\b[^>]*\\b(src|SRC|src2|SRC2)\\b\\s*=\\s*('|\")?([^'\"\n\r\f>]+(\\.jpg|\\.bmp|\\.eps|\\.gif|\\.mif|\\.miff|\\.png|\\.tif|\\.tiff|\\.svg|\\.wmf|\\.jpe|\\.jpeg|\\.dib|\\.ico|\\.tga|\\.cut|\\.pic)\\b)[^>]*>";
List<String> imgList = new ArrayList<String>(); // 存放圖片的list
String content = null;
content = getHtmlCode(httpUrl); // 獲得content
Pattern pattern = Pattern.compile(searchImgReg); // 講編譯的正則表達式對象賦給pattern
Matcher matcher = pattern.matcher(content); // 對字符串content執行正則表達式
while (matcher.find()) {
String quote = matcher.group(3);
String imgsrc = (quote == null || quote.trim().length() == 0) ? matcher.group(4).split("\\s+")[0] : matcher.group(4);
if (!imgsrc.startsWith("http://") && !imgsrc.startsWith("https://")) { // 檢驗地址是否http://
String[] httpUrlarr = httpUrl.split("/");
String wwwhost = httpUrlarr[0] + "//" + httpUrlarr[2]; //獲取域名完整地址
if(!isNetFileAvailable(wwwhost + "/" + imgsrc)){
for(int i=3;i<httpUrlarr.length;i++){
wwwhost = wwwhost + "/" + httpUrlarr[i];
if(isNetFileAvailable(wwwhost + "/" + imgsrc)){
imgsrc = wwwhost + "/" + imgsrc;
break;
}
}
}else{
imgsrc = wwwhost + "/" + imgsrc;
}
}
imgList.add(imgsrc);
}
return imgList;
}
/**
* 獲取網頁的標題
*
* @param httpUrl
* 要爬的網頁連接
* @return
*/
public static String getTilte(String httpUrl) {
String searchTitle = "(<title>|<TITLE>)(.*?)(</title>|</TITLE>)"; // 獲取網頁的標題的正則表達式
Pattern pattern = Pattern.compile(searchTitle); // 獲得content
try {
Matcher matcher = pattern.matcher(getHtmlCode(httpUrl));
while (matcher.find()) {
return matcher.group(2);
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
/**
* 檢測網絡資源是否存在
*
* @param strUrl
* @return
*/
public static boolean isNetFileAvailable(String strUrl) {
InputStream netFileInputStream = null;
try {
URL url = new URL(strUrl);
URLConnection urlConn = url.openConnection();
netFileInputStream = urlConn.getInputStream();
if (null != netFileInputStream) {
return true;
} else {
return false;
}
} catch (IOException e) {
return false;
} finally {
try {
if (netFileInputStream != null)
netFileInputStream.close();
} catch (IOException e) {
}
}
}
}