Java实现发送Http请求JDK中提供了一些对无状态协议请求（HTTP）的支持：首先让我们先构建一个请求类（HttpRequester）。

该类封装了JAVA实现简单请求的代码，如下：import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import .HttpURLConnection;import .URL;import java.nio.charset.Charset;import java.util.Map;import java.util.Vector;/*** HTTP请求对象** @author YYmmiinngg*/public class HttpRequester {private String defaultContentEncoding;public HttpRequester() {this.defaultContentEncoding = Charset.defaultCharset().name();}/*** 发送GET请求** @param urlString* URL地址* @return 响应对象* @throws IOException*/public HttpRespons sendGet(String urlString) throws IOException { return this.send(urlString, "GET", null, null);}/*** 发送GET请求** @param urlString* URL地址* @param params* 参数集合* @return 响应对象* @throws IOException*/public HttpRespons sendGet(String urlString, Map<String, String> params) throws IOException {return this.send(urlString, "GET", params, null);}/*** 发送GET请求** @param urlString* URL地址* @param params* 参数集合* @param propertys* 请求属性* @return 响应对象* @throws IOException*/public HttpRespons sendGet(String urlString, Map<String, String> params, Map<String, String> propertys) throws IOException { return this.send(urlString, "GET", params, propertys);}/*** 发送POST请求** @param urlString* URL地址* @return 响应对象* @throws IOException*/public HttpRespons sendPost(String urlString) throws IOException { return this.send(urlString, "POST", null, null);}/*** 发送POST请求** @param urlString* URL地址* @param params* 参数集合* @return 响应对象* @throws IOException*/public HttpRespons sendPost(String urlString, Map<String, String> params) throws IOException {return this.send(urlString, "POST", params, null);}/*** 发送POST请求** @param urlString* URL地址* @param params* 参数集合* @param propertys* 请求属性* @return 响应对象* @throws IOException*/public HttpRespons sendPost(String urlString, Map<String, String> params, Map<String, String> propertys) throws IOException { return this.send(urlString, "POST", params, propertys);}/*** 发送HTTP请求** @param urlString* @return 响映对象* @throws IOException*/private HttpRespons send(String urlString, String method,Map<String, String> parameters, Map<String, String> propertys)throws IOException {HttpURLConnection urlConnection = null;if (method.equalsIgnoreCase("GET") && parameters != null) {StringBuffer param = new StringBuffer();int i = 0;for (String key : parameters.keySet()) {if (i == 0)param.append("?");elseparam.append("&");param.append(key).append("=").append(parameters.get(key));i++;}urlString += param;}URL url = new URL(urlString);urlConnection = (HttpURLConnection) url.openConnection();urlConnection.setRequestMethod(method);urlConnection.setDoOutput(true);urlConnection.setDoInput(true);urlConnection.setUseCaches(false);if (propertys != null)for (String key : propertys.keySet()) {urlConnection.addRequestProperty(key, propertys.get(key));}if (method.equalsIgnoreCase("POST") && parameters != null) { StringBuffer param = new StringBuffer();for (String key : parameters.keySet()) {param.append("&");param.append(key).append("=").append(parameters.get(key));}urlConnection.getOutputStream().write(param.toString().getBytes());urlConnection.getOutputStream().flush();urlConnection.getOutputStream().close();}return this.makeContent(urlString, urlConnection);}/*** 得到响应对象** @param urlConnection* @return 响应对象* @throws IOException*/private HttpRespons makeContent(String urlString,HttpURLConnection urlConnection) throws IOException { HttpRespons httpResponser = new HttpRespons();try {InputStream in = urlConnection.getInputStream();BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(in));httpResponser.contentCollection = new Vector<String>(); StringBuffer temp = new StringBuffer();String line = bufferedReader.readLine();while (line != null) {httpResponser.contentCollection.add(line);temp.append(line).append("\r\n");line = bufferedReader.readLine();}bufferedReader.close();String ecod = urlConnection.getContentEncoding();if (ecod == null)ecod = this.defaultContentEncoding;httpResponser.urlString = urlString;httpResponser.defaultPort = urlConnection.getURL().getDefaultPort(); httpResponser.file = urlConnection.getURL().getFile(); httpResponser.host = urlConnection.getURL().getHost(); httpResponser.path = urlConnection.getURL().getPath(); httpResponser.port = urlConnection.getURL().getPort();httpResponser.protocol = urlConnection.getURL().getProtocol();httpResponser.query = urlConnection.getURL().getQuery();httpResponser.ref = urlConnection.getURL().getRef();erInfo = urlConnection.getURL().getUserInfo();httpResponser.content = new String(temp.toString().getBytes(), ecod);httpResponser.contentEncoding = ecod;httpResponser.code = urlConnection.getResponseCode();httpResponser.message = urlConnection.getResponseMessage();httpResponser.contentType = urlConnection.getContentType();httpResponser.method = urlConnection.getRequestMethod();httpResponser.connectTimeout = urlConnection.getConnectTimeout();httpResponser.readTimeout = urlConnection.getReadTimeout();return httpResponser;} catch (IOException e) {throw e;} finally {if (urlConnection != null)urlConnection.disconnect();}}/*** 默认的响应字符集*/public String getDefaultContentEncoding() {return this.defaultContentEncoding;}/*** 设置默认的响应字符集*/public void setDefaultContentEncoding(String defaultContentEncoding) { this.defaultContentEncoding = defaultContentEncoding;}}其次我们来看看响应对象（HttpRespons）。