HtmlUnit2.14使用样例—获取动态网页

标签: 简书笔记

转自:http://shihlei.iteye.com/blog/2067707

一、概述

HttpClient适合处理静态资源,网络爬虫等类似应用很大程度需要处理动态网页(内容有js填充,如百度图片,body里基本没有数据,碰到最麻烦的是新浪微博列表页)。将网页下载后,结合JS和Dom模型还原网页,我目前还未攻破,但在下载层还原网页,HtmlUnit是一种解决方案,虽然对JS的支持还是不完美。
HtmlUnit其实是自动化测试工具,集成了下载(HttpClient),Dom(NekoHtml),驱动JS(Rhino)。有一定的网页渲染能力,由于会驱动Dom,会消耗些CPU,内存。
本文描述HTMLUnit请求响应,设置cookies,设置代理,驱动JS等方法。

二、版本

pom.xml 依赖

<dependency>
            <groupId>net.sourceforge.htmlunit</groupId>
            <artifactId>htmlunit</artifactId>
            <version>2.14</version>
        </dependency>
        
        <dependency>
            <groupId>xml-apis</groupId>
            <artifactId>xml-apis</artifactId>
            <version>1.4.01</version>
        </dependency>
        
        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-java</artifactId>
            <version>3.11.0</version>
        </dependency>

三、典型功能

1、打开百度


public static void main(String[] args) throws Exception {  
    String url = "http://www.baidu.com";  
  
    final WebClient webClient = new WebClient();  
    HtmlPage htmlPage = webClient.getPage(url);  
  
    // HtmlUnit dom模型  
    // 获取表单 ,获得form标签name属性=f  
    HtmlForm form = htmlPage.getFormByName("f");  
    // 获取输入框, 获取 input标签 ,name属性=q  
    HtmlTextInput text = form.getInputByName("q");  
    // 搜索百度  
    text.setText("baidu");  
    // 获取提交按钮  
    HtmlSubmitInput button = form.getInputByName("btnG");  
    // 提交表单  
    HtmlPage listPage = button.click();  
  
    System.out.println(listPage.asXml());  
           
      webClient.closeAllWindows();  
}  
   

2、获取动态页面

/** 
 * 获取百度图片js后的内容 
 *  
 * @throws Exception 
 */  
public void demo2() throws Exception {  
    String url = "http://image.baidu.com/i?tn=baiduimage&ipn=r&ct=201326592&cl=2&lm=-1&st=-1&fm=result&fr=&sf=1&fmq=1400328281672_R&pv=&ic=0&nc=1&z=&se=1&showtab=0&fb=0&width=&height=&face=0&istype=2&ie=utf-8&word=html";  
  
    final WebClient webClient = new WebClient();  
  
    // 1 启动JS  
    webClient.getOptions().setJavaScriptEnabled(true);  
    // 2 禁用Css,可避免自动二次请求CSS进行渲染  
    webClient.getOptions().setCssEnabled(false);  
    // 3 启动客户端重定向  
    webClient.getOptions().setRedirectEnabled(true);  
  
    // 4 js运行错误时,是否抛出异常  
    webClient.getOptions().setThrowExceptionOnScriptError(false);  
    // 5 设置超时  
    webClient.getOptions().setTimeout(50000);  
      
    HtmlPage htmlPage = webClient.getPage(url);  
    // 等待JS驱动dom完成获得还原后的网页  
    webClient.waitForBackgroundJavaScript(10000);  
    // 网页内容  
    System.out.println(htmlPage.asXml());  
    webClient.closeAllWindows();  
}  

四、Demo

1 请求响应

/** 
 * Get请求 
 * @param url 
 * @return 
 * @throws Exception 
 */  
public static byte[] sendGetRequest(String url) throws Exception{  
        WebClient webClient = new WebClient();  
    WebRequest webRequest = new WebRequest(new URL(url));  
    webRequest.setHttpMethod(HttpMethod.GET);  
    return sendRequest(webClient,webRequest);  
}  
  
/** 
 * Post 请求 
 *  
 * @param url 
 * @param params 
 * @return 
 * @throws Exception 
 */  
public static byte[] sendPostRequest(String url,Map<String,String> params) throws Exception{  
        WebClient webClient = new WebClient();  
    WebRequest webRequest = new WebRequest(new URL(url));  
    webRequest.setHttpMethod(HttpMethod.POST);  
    if (params != null && params.size() > 0) {  
        for (Entry<String, String> param : params.entrySet()) {  
            webRequest.getRequestParameters().add(new NameValuePair(param.getKey(), param.getValue()));  
        }  
    }  
    return sendRequest(webClient,webRequest);  
}  
  
//底层请求  
private static byte[] sendRequest(WebClient webClient,WebRequest webRequest) throws Exception{  
    byte[] responseContent = null;  
    Page page = webClient.getPage(webRequest);  
      
    WebResponse webResponse = page.getWebResponse();  
      
    int status = webResponse.getStatusCode();  
      
    System.out.println("Charset : " + webResponse.getContentCharset());  
  
    System.out.println("ContentType : " + webResponse.getContentType());  
  
    // 读取数据内容  
    if (status==200) {  
        if (page.isHtmlPage()) {  
            <strong>// 等待JS执行完成,包括远程JS文件请求,Dom处理  
             webClient.waitForBackgroundJavaScript(10000);</strong>  
<strong>                     // 使用JS还原网页  
             responseContent = ((HtmlPage) page).asXml().getBytes();</strong>  
        } else {  
            InputStream bodyStream = webResponse.getContentAsStream();  
            responseContent = ByteStreams.toByteArray(bodyStream);  
            bodyStream.close();  
        }  
    }  
    // 关闭响应流  
    webResponse.cleanUp();  
  
    return responseContent;  
}  

2、配置JS,CSS,超时,重定向


private void configWebClient(WebClient webClient) {  
    // 设置webClient的相关参数  
    // 1 启动JS  
    webClient.getOptions().setJavaScriptEnabled(true);  
    // 2 禁用Css,可避免自动二次请求CSS进行渲染  
    webClient.getOptions().setCssEnabled(false);  
    // 3 启动客户端重定向  
    webClient.getOptions().setRedirectEnabled(true);  
  
    // 4 js运行错误时,是否抛出异常  
    webClient.getOptions().setThrowExceptionOnScriptError(false);  
    // 5 设置超时  
    webClient.getOptions().setTimeout(timeout);  
} 

3、代理


  private void setProxy(WebClient webClient,HttpProxy proxy) {  
    ProxyConfig proxyConfig = webClient.getOptions().getProxyConfig();  
    proxyConfig.setProxyHost(proxy.getHost());  
    proxyConfig.setProxyPort(proxy.getPort());  
  
    DefaultCredentialsProvider credentialsProvider = (DefaultCredentialsProvider) webClient  
            .getCredentialsProvider();  
    credentialsProvider.addCredentials(proxy.getUser(), proxy.getPassword());  
}  

4、辅助类


public class HttpProxy {
    private String proxy = "http";
    private String host;
    private int port;
    private String user;
    private String password;

    public String getProxy() {
        return proxy;
    }

    public void setProxy(String proxy) {
        this.proxy = proxy;
    }

    public String getHost() {
        return host;
    }

    public void setHost(String host) {
        this.host = host;
    }

    public int getPort() {
        return port;
    }

    public void setPort(int port) {
        this.port = port;
    }

    public String getUser() {
        return user;
    }

    public void setUser(String user) {
        this.user = user;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

五、Cookies:可以用于认证数据设置

1)设置Cookies


private void setCookies(WebClient webClient,String domain, Map<String, String> cookies) {  
    if (cookies != null && cookies.size() > 0) {  
        webClient.getCookieManager().setCookiesEnabled(true);// enable  
                                                                // cookies  
        for (Entry<String, String> c : cookies.entrySet()) {  
            Cookie cookie = new Cookie(domain, c.getKey(), c.getValue());  
            webClient.getCookieManager().addCookie(cookie);  
        }  
    }  
}  


2)获取响应Cookies


private Map<String, String> getResponseCookies(WebClient webClient) {  
    Set<Cookie> cookies = webClient.getCookieManager().getCookies();  
    Map<String, String> responseCookies = Maps.newHashMap();  
    for (Cookie c : cookies) {  
        responseCookies.put(c.getName(), c.getValue());  
    }  
    return responseCookies;  
}  

3)删除所有Cookies


/** 
 * 清除所有cookie 
 */  
public void clearCookies(WebClient webClient) {  
    webClient.getCookieManager().clearCookies();  
}  

六、驱动JS

可实现自动化流程,如驱动表单提交,获取表单提交后的页面
如登录后页面:


public void doWeb(Page page) {  
    if (page instanceof HtmlPage) {  
        StringBuilder js = new StringBuilder();  
        js.append("document.getElementsByName('username')[1].value='").append(WeiboAccount.USERNAME)  
                .append("';");  
        js.append("document.getElementsByName('password')[1].value='").append(WeiboAccount.PASSWORD)  
                .append("';");  
        js.append("document.getElementsByClassName('W_btn_g')[1].click();");  
        HtmlPage htmlPage = (HtmlPage) page;  
        htmlPage.executeJavaScript(js.toString());  
    }  
} 

七、附录:完整代码

import com.gargoylesoftware.htmlunit.*;
import com.gargoylesoftware.htmlunit.html.HtmlPage;
import com.gargoylesoftware.htmlunit.util.Cookie;
import com.google.common.collect.Maps;
import com.google.common.io.ByteStreams;
import com.jdd.basedata.commons.bean.HttpProxy;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;


public class HtmlUnitDemo {  
  
    private WebClient webClient = null;  
  
    private int timeout = 50000;  
  
    public HtmlUnitDemo() {  
        this(null);  
    }  
  
    /** 
     * Get请求 
     *  
     * @param url 
     * @return 
     * @throws Exception 
     */  
    public byte[] sendGetRequest(String url) throws Exception {  
        WebRequest webRequest = new WebRequest(new URL(url));  
        webRequest.setHttpMethod(HttpMethod.GET);  
        return sendRequest(webRequest);  
    }  
  
    /** 
     * Post 请求 
     *  
     * @param url 
     * @param params 
     * @return 
     * @throws Exception 
     */  
    public byte[] sendPostRequest(String url, Map<String, String> params) throws Exception {  
        WebRequest webRequest = new WebRequest(new URL(url));  
        webRequest.setHttpMethod(HttpMethod.POST);  
        if (params != null && params.size() > 0) {  
            for (Entry<String, String> param : params.entrySet()) {  
                webRequest.getRequestParameters().add(new NameValuePair(param.getKey(), param.getValue()));  
            }  
        }  
        return sendRequest(webRequest);  
    }  
  
    // 底层请求  
    private byte[] sendRequest(WebRequest webRequest) throws Exception {  
        byte[] responseContent = null;  
        Page page = webClient.getPage(webRequest);  
  
        WebResponse webResponse = page.getWebResponse();  
  
        int status = webResponse.getStatusCode();  
  
        System.out.println("Charset : " + webResponse.getContentCharset());  
  
        System.out.println("ContentType : " + webResponse.getContentType());  
  
        // 读取数据内容  
        if (status == 200) {  
            if (page.isHtmlPage()) {  
                // 等待JS执行完成  
                webClient.waitForBackgroundJavaScript(100000);  
                responseContent = ((HtmlPage) page).asXml().getBytes();  
            } else {  
                InputStream bodyStream = webResponse.getContentAsStream();  
                responseContent = ByteStreams.toByteArray(bodyStream);  
                bodyStream.close();  
            }  
        }  
        // 关闭响应流  
        webResponse.cleanUp();  
  
        return responseContent;  
    }  
  
    public HtmlUnitDemo(HttpProxy proxy) {  
        webClient = new WebClient();  
        configWebClient();  
        // 设置代理  
        if (proxy != null) {  
            setProxy(proxy);  
        }  
    }  
  
    private void configWebClient() {  
        // 设置webClient的相关参数  
        // 1 启动JS  
        webClient.getOptions().setJavaScriptEnabled(true);  
        // 2 禁用Css,可避免自动二次请求CSS进行渲染  
        webClient.getOptions().setCssEnabled(false);  
        // 3 启动客户端重定向  
        webClient.getOptions().setRedirectEnabled(true);  
  
        // 4 js运行错误时,是否抛出异常  
        webClient.getOptions().setThrowExceptionOnScriptError(false);  
        // 5 设置超时  
        webClient.getOptions().setTimeout(timeout);  
    }  
  
    private void setProxy(HttpProxy proxy) {  
        ProxyConfig proxyConfig = webClient.getOptions().getProxyConfig();  
        proxyConfig.setProxyHost(proxy.getHost());  
        proxyConfig.setProxyPort(proxy.getPort());  
  
        DefaultCredentialsProvider credentialsProvider = (DefaultCredentialsProvider) webClient  
                .getCredentialsProvider();  
        credentialsProvider.addCredentials(proxy.getUser(), proxy.getPassword());  
    }  
  
    @SuppressWarnings("unused")  
    private Map<String, String> getResponseCookies() {  
        Set<Cookie> cookies = webClient.getCookieManager().getCookies();  
        Map<String, String> responseCookies = Maps.newHashMap();  
        for (Cookie c : cookies) {  
            responseCookies.put(c.getName(), c.getValue());  
        }  
        return responseCookies;  
    }  
  
    @SuppressWarnings("unused")  
    private void setCookies(String domain, Map<String, String> cookies) {  
        if (cookies != null && cookies.size() > 0) {  
            webClient.getCookieManager().setCookiesEnabled(true);// enable  
                                                                    // cookies  
            for (Entry<String, String> c : cookies.entrySet()) {  
                Cookie cookie = new Cookie(domain, c.getKey(), c.getValue());  
                webClient.getCookieManager().addCookie(cookie);  
  
                System.out.println("Set Cookies : " + c.getKey() + " | " + c.getValue());  
            }  
        }  
    }  
  
    /** 
     * 清除所有cookie 
     */  
    public void clearCookies() {  
        webClient.getCookieManager().clearCookies();  
    }  
  
    public void shutdown() throws IOException {  
        webClient.closeAllWindows();  
    }  
  
    /** 
     * 打开google 搜索百度 
     *  
     * @param args 
     * @throws Exception 
     */  
    public void demo() throws Exception{  
        String url = "http://www.google.com.hk";  
  
        final WebClient webClient = new WebClient();  
        HtmlPage htmlPage = webClient.getPage(url);  
  
        // HtmlUnit dom模型  
        // 获取表单 ,获得form标签name属性=f  
        HtmlForm form = htmlPage.getFormByName("f");  
        // 获取输入框, 获取 input标签 ,name属性=q  
        HtmlTextInput text = form.getInputByName("q");  
        // 搜索百度  
        text.setText("baidu");  
        // 获取提交按钮  
        HtmlSubmitInput button = form.getInputByName("btnG");  
        // 提交表单  
        HtmlPage listPage = button.click();  
  
        System.out.println(listPage.asXml());  
        webClient.closeAllWindows();  
    }  
    
    /** 
     * 打开百度 
     *  
     * @param args 
     * @throws Exception 
     */  
    public static void main(String[] args) throws Exception {  
        String url = "http://www.baidu.com";  
  
        HtmlUnitDemo htmlUnit = new HtmlUnitDemo();  
        byte[] getResponse = htmlUnit.sendGetRequest(url);  
        System.out.println("Get Body : " + new String(getResponse, "utf-8"));  
        byte[] postResponse = htmlUnit.sendPostRequest(url, null);  
        System.out.println("Get Body : " + new String(postResponse, "utf-8"));  
  
        htmlUnit.shutdown();  
    }  
}  

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