HtmlUnit 爬虫简单案例——模拟登陆CSDN

最近要弄一个爬虫程序，想着先来个简单的模拟登陆， 在权衡JxBrowser和HtmlUnit 两种技术，  JxBowser有界面呈现效果，但是对于某些js跳转之后的效果获取比较繁琐。

随后考虑用HtmlUnit， 想着借用咱们CSND的登陆练练手。谁知道CSDN的登陆，js加载时间超长，不设置长一点的加载时间，按钮提交根本没效果，js没生效。 具体看代码注释吧。 奉劝做爬虫的同志们，千万别用CSDN登陆练手，坑死我了。。。

maven配置如下：

	<dependencies>
		<!-- https://mvnrepository.com/artifact/net.sourceforge.htmlunit/htmlunit -->
		<dependency>
			<groupId>net.sourceforge.htmlunit</groupId>
			<artifactId>htmlunit</artifactId>
			<version>2.18</version>
		</dependency>
		<!-- https://mvnrepository.com/artifact/org.jsoup/jsoup -->
		<dependency>
			<groupId>org.jsoup</groupId>
			<artifactId>jsoup</artifactId>
			<version>1.9.2</version>
		</dependency>
	</dependencies>

代码如下：

/*
 * Copyright (c) 2017 Create By Shijing All Rights Reserved.
 */
package com.test;

import java.io.IOException;
import java.net.MalformedURLException;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import com.gargoylesoftware.htmlunit.BrowserVersion;
import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;
import com.gargoylesoftware.htmlunit.NicelyResynchronizingAjaxController;
import com.gargoylesoftware.htmlunit.SilentCssErrorHandler;
import com.gargoylesoftware.htmlunit.WebClient;
import com.gargoylesoftware.htmlunit.html.HtmlButtonInput;
import com.gargoylesoftware.htmlunit.html.HtmlForm;
import com.gargoylesoftware.htmlunit.html.HtmlPage;
import com.gargoylesoftware.htmlunit.html.HtmlPasswordInput;
import com.gargoylesoftware.htmlunit.html.HtmlTextInput;
import com.gargoylesoftware.htmlunit.util.Cookie;

public class SimulateLogin
{
    //访问的目标网址（CSDN）
    private static String TARGET_URL = "https://passport.csdn.net/account/login?from=http://www.csdn.net";

    public static void main(String[] args) throws FailingHttpStatusCodeException, MalformedURLException, IOException
    {
        // 模拟一个浏览器
        WebClient webClient = new WebClient(BrowserVersion.CHROME);
        // 设置webClient的相关参数
        webClient.setCssErrorHandler(new SilentCssErrorHandler());  
        //设置ajax
        webClient.setAjaxController(new NicelyResynchronizingAjaxController());
        //设置支持js
        webClient.getOptions().setJavaScriptEnabled(true);
        //CSS渲染禁止
        webClient.getOptions().setCssEnabled(false);
        //超时时间
        webClient.getOptions().setTimeout(50000);
        //设置js抛出异常:false
        webClient.getOptions().setThrowExceptionOnScriptError(false);
        //允许重定向
        webClient.getOptions().setRedirectEnabled(true);  
        //允许cookie
        webClient.getCookieManager().setCookiesEnabled(true);  
        // 模拟浏览器打开一个目标网址
        HtmlPage page = webClient.getPage(TARGET_URL);
        /**等待js加载完全，CSDN这点 特别坑，js加载时间超长！！！！！！！ 后人切记不要用CSDN模拟登陆！！！！！！！**/
        webClient.waitForBackgroundJavaScript(10000*3);
     // 根据form的名字获取页面表单，也可以通过索引来获取：page.getForms().get(0)     
        HtmlForm form = (HtmlForm) page.getElementById("fm1");         
        HtmlTextInput username = (HtmlTextInput) form.getInputByName("username");  
        HtmlPasswordInput password = (HtmlPasswordInput) form.getInputByName("password");  
        username.setValueAttribute("********");  //用户名
        password.setValueAttribute("********");  //密码
        HtmlButtonInput button  = (HtmlButtonInput) page.getByXPath("//input[contains(@class, 'logging')]").get(0);
//        ScriptResult result = page.executeJavaScript("javascript:document.getElementsByClassName('logging')[0].click()");
//        HtmlPage retPage = (HtmlPage) result.getNewPage();
        HtmlPage retPage = button.click();
        // 等待JS驱动dom完成获得还原后的网页  
        webClient.waitForBackgroundJavaScript(1000);  
        //输出跳转网页的地址
        System.out.println(retPage.getUrl().toString());   
        //输出跳转网页的内容
        System.out.println(retPage.asXml());

        //获取cookie  
        Set<Cookie> cookies = webClient.getCookieManager().getCookies();
        Map<String, String> responseCookies = new HashMap<String, String>();  
        for (Cookie c : cookies) {  
            responseCookies.put(c.getName(), c.getValue());  
            System.out.print(c.getName()+":"+c.getValue());  
        }  
        webClient.close();
        System.out.println("Success!");
    }
}

另外， CSDN的JS总是莫名其妙的报一堆错，如果不想看，想忽略的话，在创建WebClient前加上如下代码：

        //设置日志级别，原页面js异常不打印
        LogFactory.getFactory().setAttribute("org.apache.commons.logging.Log",    "org.apache.commons.logging.impl.NoOpLog");  
        
        java.util.logging.Logger.getLogger("com.gargoylesoftware.htmlunit")  
            .setLevel(Level.OFF);  
  
        java.util.logging.Logger.getLogger("org.apache.commons.httpclient")  
            .setLevel(Level.OFF);