Zhihu.java
import java.util.ArrayList; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Zhihu { public String question;// 问题 public String questionDescription;// 问题描述 public String zhihuUrl;// 网页链接 public ArrayList<String> answers;// 存储所有回答的数组 // 构造方法初始化数据 public Zhihu(String url) { // 初始化属性 question = ""; questionDescription = ""; zhihuUrl = ""; answers = new ArrayList<String>(); // 判断url是否合法 if (getRealUrl(url)) { System.out.println("正在抓取" + zhihuUrl); // 根据url获取该问答的细节 String content = Spider.SendGet(zhihuUrl); Pattern pattern; Matcher matcher; // 匹配标题 pattern = Pattern.compile("zh-question-title.+?<h2 id="">(.+?)</h2>"); matcher = pattern.matcher(content); if (matcher.find()) { question = matcher.group(1); } // 匹配描述 pattern = Pattern .compile("zh-question-detail.+?<div.+?>(.*?)</div>"); matcher = pattern.matcher(content); if (matcher.find()) { questionDescription = matcher.group(1); } // 匹配答案 pattern = Pattern.compile("/answer/content.+?<div.+?>(.*?)</div>"); matcher = pattern.matcher(content); boolean isFind = matcher.find(); while (isFind) { answers.add(matcher.group(1)); isFind = matcher.find(); } } } // 根据自己的url抓取自己的问题和描述和答案 public boolean getAll() { return true; } // 处理url boolean getRealUrl(String url) { // 将http://www.zhihu.com/question/22355264/answer/21102139 // 转化成http://www.zhihu.com/question/22355264 // 否则不变 Pattern pattern = Pattern.compile("question/(.*?)/"); Matcher matcher = pattern.matcher(url); if (matcher.find()) { zhihuUrl = "http://www.zhihu.com/question/" + matcher.group(1); } else { return false; } return true; } @Override public String toString() { return "问题:" + question + "\n" + "描述:" + questionDescription + "\n" + "链接:" + zhihuUrl + "\n回答:" + answers.size() + "\n"; } }
Spider.java
import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.URL; import java.net.URLConnection; import java.util.ArrayList; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Spider { static String SendGet(String url) { // 定义一个字符串用来存储网页内容 String result = ""; // 定义一个缓冲字符输入流 BufferedReader in = null; try { // 将string转成url对象 URL realUrl = new URL(url); // 初始化一个链接到那个url的连接 URLConnection connection = realUrl.openConnection(); // 开始实际的连接 connection.connect(); // 初始化 BufferedReader输入流来读取URL的响应 in = new BufferedReader(new InputStreamReader( connection.getInputStream(), "UTF-8")); // 用来临时存储抓取到的每一行的数据 String line; while ((line = in.readLine()) != null) { // 遍历抓取到的每一行并将其存储到result里面 result += line; } } catch (Exception e) { System.out.println("发送GET请求出现异常!" + e); e.printStackTrace(); } // 使用finally来关闭输入流 finally { try { if (in != null) { in.close(); } } catch (Exception e2) { e2.printStackTrace(); } } return result; } // 获取所有的编辑推荐的知乎内容 static ArrayList<Zhihu> GetRecommendations(String content) { // 预定义一个ArrayList来存储结果 ArrayList<Zhihu> results = new ArrayList<Zhihu>(); // 用来匹配url,也就是问题的链接 Pattern pattern = Pattern .compile("<h2 id="question-link-href">.+?question_link.+?href=\"(.+?)\".+?</h2>"); Matcher matcher = pattern.matcher(content); // 是否存在匹配成功的对象 Boolean isFind = matcher.find(); while (isFind) { // 定义一个知乎对象来存储抓取到的信息 Zhihu zhihuTemp = new Zhihu(matcher.group(1)); // 添加成功匹配的结果 results.add(zhihuTemp); // 继续查找下一个匹配对象 isFind = matcher.find(); } return results; } }
The above is the content of writing Java Zhihu crawler to grab Zhihu answers (2) from scratch. For more related content, please pay attention to the PHP Chinese website (www.php.cn) !

JavaachievesplatformindependencethroughtheJavaVirtualMachine(JVM),allowingcodetorunondifferentoperatingsystemswithoutmodification.TheJVMcompilesJavacodeintoplatform-independentbytecode,whichittheninterpretsandexecutesonthespecificOS,abstractingawayOS

Javaispowerfulduetoitsplatformindependence,object-orientednature,richstandardlibrary,performancecapabilities,andstrongsecurityfeatures.1)PlatformindependenceallowsapplicationstorunonanydevicesupportingJava.2)Object-orientedprogrammingpromotesmodulara

The top Java functions include: 1) object-oriented programming, supporting polymorphism, improving code flexibility and maintainability; 2) exception handling mechanism, improving code robustness through try-catch-finally blocks; 3) garbage collection, simplifying memory management; 4) generics, enhancing type safety; 5) ambda expressions and functional programming to make the code more concise and expressive; 6) rich standard libraries, providing optimized data structures and algorithms.

JavaisnotentirelyplatformindependentduetoJVMvariationsandnativecodeintegration,butitlargelyupholdsitsWORApromise.1)JavacompilestobytecoderunbytheJVM,allowingcross-platformexecution.2)However,eachplatformrequiresaspecificJVM,anddifferencesinJVMimpleme

TheJavaVirtualMachine(JVM)isanabstractcomputingmachinecrucialforJavaexecutionasitrunsJavabytecode,enablingthe"writeonce,runanywhere"capability.TheJVM'skeycomponentsinclude:1)ClassLoader,whichloads,links,andinitializesclasses;2)RuntimeDataAr

Javaremainsagoodlanguageduetoitscontinuousevolutionandrobustecosystem.1)Lambdaexpressionsenhancecodereadabilityandenablefunctionalprogramming.2)Streamsallowforefficientdataprocessing,particularlywithlargedatasets.3)ThemodularsystemintroducedinJava9im

Javaisgreatduetoitsplatformindependence,robustOOPsupport,extensivelibraries,andstrongcommunity.1)PlatformindependenceviaJVMallowscodetorunonvariousplatforms.2)OOPfeatureslikeencapsulation,inheritance,andpolymorphismenablemodularandscalablecode.3)Rich

The five major features of Java are polymorphism, Lambda expressions, StreamsAPI, generics and exception handling. 1. Polymorphism allows objects of different classes to be used as objects of common base classes. 2. Lambda expressions make the code more concise, especially suitable for handling collections and streams. 3.StreamsAPI efficiently processes large data sets and supports declarative operations. 4. Generics provide type safety and reusability, and type errors are caught during compilation. 5. Exception handling helps handle errors elegantly and write reliable software.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Atom editor mac version download
The most popular open source editor

WebStorm Mac version
Useful JavaScript development tools

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
