包括POST请求，GET请求。以及请求UTF-8编码。
代码如下：
import org.apache.commons.lang.StringUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.io.*; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.net.URLEncoder; import java.util.List; import java.util.Map; /** * Created by lsy */ public class HttpUtil { public static final String DEFAULT_CHARSET = "utf-8"; public static final Log logger = LogFactory.getLog(HttpUtil.class); public static String doGet(String baseUrl, Map<String, String> paramMap) { StringBuffer queryString = new StringBuffer(); for (String param : paramMap.keySet()) { String value = paramMap.get(param); if (StringUtils.isNotBlank(value)) { try { value = URLEncoder.encode(value, DEFAULT_CHARSET); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } queryString.append(param).append("=").append(value).append("&"); } } return doGet(baseUrl, queryString.toString()); } /** * 向指定URL发送GET方法的请求 * * @param baseUrl 发送请求的URL * @param param 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。 * @return URL 所代表远程资源的响应结果 */ public static String doGet(String baseUrl, String param) { String result = ""; BufferedReader in = null; try { String urlNameString =baseUrl; if(param!=null){ urlNameString = baseUrl + "?" + param; } logger.info("http请求：" + urlNameString); URL realUrl = new URL(urlNameString); // 打开和URL之间的连接 HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection(); // 设置通用的请求属性 connection.setRequestProperty("Content-Type", "text/plain; charset=utf-8"); connection.setRequestProperty("Charsert", DEFAULT_CHARSET); connection.setRequestProperty("accept", "*/*"); connection.setRequestProperty("connection", "Keep-Alive"); connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 建立实际的连接 connection.connect(); if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) { // 获取所有响应头字段 Map<String, List<String>> map = connection.getHeaderFields(); // 遍历所有的响应头字段 for (String key : map.keySet()) { logger.info(key + "--->" + map.get(key)); } // 定义 BufferedReader输入流来读取URL的响应 in = new BufferedReader(new InputStreamReader( connection.getInputStream())); String line; while ((line = in.readLine()) != null) { result += line; } } } catch (Exception e) { logger.info("发送GET请求出现异常！" + e); e.printStackTrace(); } // 使用finally块来关闭输入流 finally { try { if (in != null) { in.close(); } } catch (Exception e2) { e2.printStackTrace(); } } return result; } public static String doGet(String baseUrl) { return doGet(baseUrl,""); } /** * 向指定 URL 发送POST方法的请求 * * @param url 发送请求的 URL * @param param 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。 * @return 所代表远程资源的响应结果 */ public static String doPost(String url, String param) { PrintWriter out = null; BufferedReader in = null; String result = ""; try { URL realUrl = new URL(url); // 打开和URL之间的连接 URLConnection connection = realUrl.openConnection(); // 设置通用的请求属性 connection.setRequestProperty("Content-Type", "text/plain; charset=utf-8"); connection.setRequestProperty("Charsert", "UTF-8"); connection.setRequestProperty("accept", "*/*"); connection.setRequestProperty("connection", "Keep-Alive"); connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 发送POST请求必须设置如下两行 connection.setDoOutput(true); connection.setDoInput(true); // 获取URLConnection对象对应的输出流 out = new PrintWriter(connection.getOutputStream()); // 发送请求参数 out.print(param); // flush输出流的缓冲 out.flush(); // 定义BufferedReader输入流来读取URL的响应 in = new BufferedReader( new InputStreamReader(connection.getInputStream())); String line; while ((line = in.readLine()) != null) { result += line; } } catch (Exception e) { logger.info("发送 POST 请求出现异常！" + e); e.printStackTrace(); } //使用finally块来关闭输出流、输入流 finally { try { if (out != null) { out.close(); } if (in != null) { in.close(); } } catch (IOException ex) { ex.printStackTrace(); } } return result; } }