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需要下载jar包：commons-httpclient
下载地址： 4.1.2
2. 获取网页内容
package cn.edu.xmu.utils;import java.util.regex.Matcher;import java.util.regex.Pattern;import org.apache.http.Header;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.HttpStatus;import org.apache.http.client.HttpClient;import org.apache.http.client.methods.HttpGet;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.util.EntityUtils;public class WebPageGetter { public static String getWebPage(String url) throws Exception { // 初始化，与3.1中不同 HttpClient httpclient = new DefaultHttpClient(); // HttpHost targetHost = new HttpHost("http://www.kinkbomb.com/p/9699"); // HttpGet httpget = new HttpGet("http://www.apache.org/"); HttpGet httpget = new HttpGet(url); // 查看默认request头部信息 System.out.println("Accept-Charset:" + httpget.getFirstHeader("Accept-Charset")); // 以下这条如果不加会发现无论你设置Accept-Charset为gbk还是utf-8，他都会默认返回gb2312（本例针对google.cn来说） httpget.setHeader("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1.2)"); // 用逗号分隔显示可以同时接受多种编码 httpget.setHeader("Accept-Language", "zh-cn,zh;q=0.5"); httpget.setHeader("Accept-Charset", "GB2312,utf-8;q=0.7,*;q=0.7"); // 验证头部信息设置生效 System.out.println("Accept-Charset:" + httpget.getFirstHeader("Accept-Charset").getValue()); // Execute HTTP request System.out.println("executing request " + httpget.getURI()); // HttpResponse response = httpclient.execute(targetHost, httpget); HttpResponse response = httpclient.execute(httpget); // HttpResponse response = httpclient.execute(httpget); System.out.println("----------------------------------------"); System.out.println("Location: " + response.getLastHeader("Location")); System.out.println(response.getStatusLine().getStatusCode()); System.out.println(response.getLastHeader("Content-Type")); System.out.println(response.getLastHeader("Content-Length")); System.out.println("----------------------------------------"); // 判断页面返回状态判断是否进行转向抓取新链接 int statusCode = response.getStatusLine().getStatusCode(); if ((statusCode == HttpStatus.SC_MOVED_PERMANENTLY) || (statusCode == HttpStatus.SC_MOVED_TEMPORARILY) || (statusCode == HttpStatus.SC_SEE_OTHER) || (statusCode == HttpStatus.SC_TEMPORARY_REDIRECT)) { // 此处重定向处理 此处还未验证 String newUri = response.getLastHeader("Location").getValue(); httpclient = new DefaultHttpClient(); httpget = new HttpGet(newUri); response = httpclient.execute(httpget); } // Get hold of the response entity HttpEntity entity = response.getEntity(); // 查看所有返回头部信息 Header headers[] = response.getAllHeaders(); int ii = 0; while (ii < headers.length) { System.out.println(headers[ii].getName() + ": " + headers[ii].getValue()); ++ii; } // If the response does not enclose an entity, there is no need // to bother about connection release byte[] bytes = null; if (entity != null) { // 将源码流保存在一个byte数组当中，因为可能需要两次用到该流， bytes = EntityUtils.toByteArray(entity); String charSet = ""; // 如果头部Content-Type中包含了编码信息，那么我们可以直接在此处获取 charSet = EntityUtils.getContentCharSet(entity); System.out.println("In header: " + charSet); // 如果头部中没有，那么我们需要 查看页面源码，这个方法虽然不能说完全正确，因为有些粗糙的网页编码者没有在页面中写头部编码信息 if (charSet == "") { String regEx = "(?= <=charset=[\\'|\\\"]?)([[a-z]|[A-Z]|[0-9]|-]*)"; Pattern p = Pattern.compile(regEx, Pattern.CASE_INSENSITIVE); Matcher m = p.matcher(new String(bytes)); // 默认编码转成字符串，因为我们的匹配中无中文，所以串中可能的乱码对我们没有影响 Boolean result = m.find(); if (m.groupCount() == 1) { charSet = m.group(1); } else { charSet = ""; } } System.out.println("Last get: " + charSet); // 至此，我们可以将原byte数组按照正常编码专成字符串输出（如果找到了编码的话） // System.out.println("Encoding string is: " + new String(bytes, // charSet)); } httpclient.getConnectionManager().shutdown(); return new String(bytes); }}
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