此类以获取天气的一个api地址为例：

package javaexcjs;import java.io.BufferedReader;import java.io.OutputStreamWriter;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.URLEncoder;import java.net.URL;import java.util.List;import java.util.Map;import java.util.Set;public class CopyOfSendPostRequest {    static String sessionId = "";    public static void main(String[] args) throws Exception {                //城市名称        String city = URLEncoder.encode("重庆", "GB2312");        System.out.println(city);        // api url ：北向URL        String locationUrl = "http://php.weather.sina.com.cn/xml.php?city=" + city + "&password=DJOYnieT8234jlsK&day=0";        // http body 消息体        String reqBody = "";        // http method        String method = "POST";        // http head : Content-Type 消息类型        String contentType = "application/json;charset=UTF-8";        // 设定连接的相关参数        URL url = new URL(locationUrl);        HttpURLConnection connection = (HttpURLConnection) url.openConnection();        connection.setDoOutput(true);        connection.setReadTimeout(10000);        connection.setRequestMethod(method);        connection.setRequestProperty("Content-Type", contentType);        //写入请求消息体        OutputStreamWriter out = new OutputStreamWriter(                connection.getOutputStream(), "UTF-8");        out.write(reqBody);        out.flush();        out.close();        // 获取服务端的反馈        String strLine = "";        StringBuilder strResponse = new StringBuilder();        try {            Map
      
       > rspHeaders = connection.getHeaderFields();            Set
       
         rspHeadNames = rspHeaders.keySet();            for (String key : rspHeadNames) {                //rspHeaders中的http状态码和描述的键为null                if (null != key) {                    strResponse.append(key + ": ");                }                strResponse.append(new String(rspHeaders.get(key).get(0)                        .getBytes("iso-8859-1"), "UTF-8")                        + "\n");            }            int code = connection.getResponseCode();            // String status = connection.getResponseMessage();            InputStream in;            // 判断http状态码            if (code == 200) {                in = connection.getInputStream();            } else {                in = connection.getErrorStream();            }            if (null != in) {                BufferedReader reader = new BufferedReader(                        new InputStreamReader(in));                while ((strLine = reader.readLine()) != null) {                    strResponse.append("\n" + strLine);                }            }            System.out.print(strResponse.toString());        } catch (Exception e) {            e.printStackTrace();        }    }}