發送Post的請求代碼

通過瀏覽器訪問的URL請求，都是GET請求，接下來代碼是模擬POST發送請求

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

public class HttpMethod {
    
    public static String executeRule(String url,String id,String analyzeModelType,String paramJson){
        String params =generateParams(id,analyzeModelType,paramJson);
        //System.out.println(params);
        try {
            sendPost(url,params);
            return "Execute Sucessfully!";
        } catch (Exception e) {
            e.printStackTrace();
            return "Execute Failed!";
        }
    }
    
    /**
     * 獲取和組裝參數
     */
    private static String generateParams(String id, String analyzeModelType, String paramJson){
        StringBuffer sb =new StringBuffer();
        sb.append("id=");
        sb.append(id);
        sb.append("&analyzeModelType=");
        sb.append(analyzeModelType);
        sb.append("&paramJson=");
        sb.append(paramJson);
        return sb.toString();
    }
    
    private static String sendPost(String url, String param) {
        PrintWriter out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            URLConnection conn = realUrl.openConnection();
            // 設置通用的請求屬性
            conn.setRequestProperty("accept", "*/*");
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setRequestProperty("user-agent","Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            conn.setDoOutput(true);
            conn.setDoInput(true);
            out = new PrintWriter(conn.getOutputStream());
            out.print(param);
            out.flush();
            try {
                in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            } catch (FileNotFoundException exception) {
                java.io.InputStream err = ((HttpURLConnection) conn).getErrorStream();
                if (err == null) throw exception;
                in = new BufferedReader(new InputStreamReader(err));
            }
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("發送 POST 請求出現異常！"+e);
            e.printStackTrace();
        }
        finally{
            try{
                if(out!=null){
                    out.close();
                }
                if(in!=null){
                    in.close();
                }
            }
            catch(IOException ex){
                ex.printStackTrace();
            }
        }
        return result;
    }  
    
}

//調用代碼
HttpMethod.executeRule(Constant.ANALYZEURL, id, analyzeModelType, URLEncoder.encode(paramJson,"UTF-8"));
//若果參數中有json串，則需要將其用URLEncoder編碼