java发送http的get和post请求

import java.io.*;
import java.net.URL;
import java.util.Map;
import java.net.HttpURLConnection;;


public class HttpRequest{
    
    public static String sendGet(String url) {
        String result = "";
        BufferedReader in = null;
        try {
            URL realurl = new URL(url);
            HttpURLConnection connection = (HttpURLConnection) realurl.openConnection();
            connection.setConnectTimeout(5000);
            connection.setRequestMethod("GET");
            in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }    
        } catch(Exception e) {
            System.out.println("发送get请求失败："+e);
            e.printStackTrace();
        } finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return result;
    }
    
    public static String sendPost(String url, String params) {
        String encoding = "UTF-8";
        String result = "";
        BufferedReader in = null;
        try {
            byte[] data = params.getBytes(encoding);
            URL base_url = new URL(url);
            HttpURLConnection conn = (HttpURLConnection) base_url.openConnection();
            conn.setReadTimeout(5000);
            conn.setRequestMethod("POST");
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setRequestProperty("Content-Type", "application/json");
            conn.setRequestProperty("Content-Length", String.valueOf(data.length));
            OutputStream outStream = conn.getOutputStream();
            outStream.write(data);
            outStream.flush();
            outStream.close();
            System.out.println(conn.getResponseCode());
            System.out.println(conn.getResponseMessage());
            if (conn.getResponseCode() == 200) {
                in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
                String line;
                while ((line = in.readLine()) != null) {
                    result += line;
                }
            }
        } catch(Exception e) {
            System.out.println("发送POST请求失败:"+e);
            e.printStackTrace();
        } finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return result;
    }
}