【搜索引擎Jediael开发4】V0.01完整代码

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截止目前，已完成如下功能：

1、指定某个地址，下载其页面中包含的所有链接指向的网页

主要有以下类：

1、主类MyCrawler

2、网页下载类PageDownloader

3、网页内容分类类HtmlParserTool

4、接口Filter

完整代码可见归档代码 Jediael_v0.01

或者

https://code.csdn.net/jediael_lu/daopattern/tree/d196da609baa59ef08176322ca61928fbfbdf813

或者

http://download.csdn.net/download/jediael_lu/7382011

1、主类MyCrawler

package org.ljh.search;

import java.io.IOException;
import java.util.Iterator;
import java.util.Set;

import org.htmlparser.Parser;
import org.ljh.search.downloadpage.PageDownloader;
import org.ljh.search.html.HtmlParserTool;
import org.ljh.search.html.LinkFilter;

public class MyCrawler {	

	public static void main(String[] args) {
		String url = "http://www.baidu.com";
		
		LinkFilter linkFilter = new LinkFilter(){
			@Override
			public boolean accept(String url) {
				if(url.contains("baidu")){
					return true;
				}else{
					return false;
				}
			}			
		};
		try {
			PageDownloader.downloadPageByGetMethod(url);
			Set<String> urlSet = HtmlParserTool.extractLinks(url, linkFilter);
			Iterator iterator = urlSet.iterator();
			while(iterator.hasNext()){
				PageDownloader.downloadPageByGetMethod((String) iterator.next());
			}
			
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}

package org.ljh.search.downloadpage;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Scanner;

import org.apache.http.HttpEntity;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;

//本类用于将指定url对应的网页下载至本地一个文件。
public class PageDownloader {

	public static void downloadPageByGetMethod(String url) throws IOException {

		// 1、通过HttpGet获取到response对象
		CloseableHttpClient httpClient = HttpClients.createDefault();
		// 注意，必需要加上http://的前缀，否则会报：Target host is null异常。
		HttpGet httpGet = new HttpGet(url);
		CloseableHttpResponse response = httpClient.execute(httpGet);

		InputStream is = null;
		if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
			try {
				// 2、获取response的entity。
				HttpEntity entity = response.getEntity();

				// 3、获取到InputStream对象，并对内容进行处理
				is = entity.getContent();

				String fileName = getFileName(url);
				saveToFile("D:\\tmp\\", fileName, is);
			} catch (ClientProtocolException e) {
				e.printStackTrace();
			} finally {

				if (is != null) {
					is.close();
				}
				if (response != null) {
					response.close();
				}
			}
		}
	}

	//将输入流中的内容输出到path指定的路径，fileName指定的文件名
	private static void saveToFile(String path, String fileName, InputStream is) {
		Scanner sc = new Scanner(is);
		Writer os = null;
		try {
			os = new PrintWriter(path + fileName);
			while (sc.hasNext()) {
				os.write(sc.nextLine());
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (sc != null) {
				sc.close();
			}
			if (os != null) {
				try{
				os.flush();
				os.close();
				}catch(IOException e){
					e.printStackTrace();
					System.out.println("输出流关闭失败！");
				}
			}
		}
	}

	// 将url中的特殊字符用下划线代替
	private static String getFileName(String url) {
		url = url.substring(7);
		String fileName = url.replaceAll("[\\?:*|<>\"/]", "_") + ".html";
		return fileName;
	}

}

package org.ljh.search.html;

import java.util.HashSet;
import java.util.Set;

import org.htmlparser.Node;
import org.htmlparser.NodeFilter;
import org.htmlparser.Parser;
import org.htmlparser.filters.NodeClassFilter;
import org.htmlparser.filters.OrFilter;
import org.htmlparser.tags.LinkTag;
import org.htmlparser.util.NodeList;
import org.htmlparser.util.ParserException;

//本类创建用于HTML文件解释工具
public class HtmlParserTool {

	// 本方法用于提取某个html文档中内嵌的链接
	public static Set<String> extractLinks(String url, LinkFilter filter) {
		Set<String> links = new HashSet<String>();
		try {
			// 1、构造一个Parser，并设置相关的属性
			Parser parser = new Parser(url);
			parser.setEncoding("gb2312");

			// 2.1、自定义一个Filter，用于过滤<Frame >标签，然后取得标签中的src属性值
			NodeFilter frameNodeFilter = new NodeFilter() {
				@Override
				public boolean accept(Node node) {
					if (node.getText().startsWith("frame src=")) {
						return true;
					} else {
						return false;
					}
				}
			};
			
			//2.2、创建第二个Filter，过滤<a>标签
			NodeFilter aNodeFilter = new NodeClassFilter(LinkTag.class);
			
			//2.3、净土上述2个Filter形成一个组合逻辑Filter。
			OrFilter linkFilter = new OrFilter(frameNodeFilter, aNodeFilter);
			
			//3、使用parser根据filter来取得所有符合条件的节点
			NodeList nodeList = parser.extractAllNodesThatMatch(linkFilter);
			
			//4、对取得的Node进行处理
			for(int i = 0; i<nodeList.size();i++){
				Node node = nodeList.elementAt(i);
				String linkURL = "";
				//如果链接类型为<a />
				if(node instanceof LinkTag){
					LinkTag link = (LinkTag)node;
					linkURL= link.getLink();
				}else{
					//如果类型为<frame />
					String nodeText = node.getText();
					int beginPosition = nodeText.indexOf("src=");
					nodeText = nodeText.substring(beginPosition);
					int endPosition = nodeText.indexOf(" ");
					if(endPosition == -1){
						endPosition = nodeText.indexOf(">");
					}
					linkURL = nodeText.substring(5, endPosition - 1);
				}
				//判断是否属于本次搜索范围的url
				if(filter.accept(linkURL)){
					links.add(linkURL);
				}
			}
			
		} catch (ParserException e) {
			e.printStackTrace();
		}
		return links;
	}
}

package org.ljh.search.html;

//本接口所定义的过滤器，用于判断url是否属于本次搜索范围。
public interface LinkFilter {
	public boolean accept(String url);
}

【搜索引擎Jediael开发4】V0.01完整代码,布布扣,bubuko.com

【搜索引擎Jediael开发4】V0.01完整代码

标签：des   class   blog   c   code   java   

原文地址：http://blog.csdn.net/jediael_lu/article/details/26509347