import org.apache.log4j.Logger;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;

public class HttpTools {

    private HttpTools(){}

    private static final Logger logger = Logger.getLogger(HttpTools.class);

    public static String httpGet(String url,String charset){
        logger.debug("发送 http get 请求 , URL : " + url);
        String result = "";
        BufferedReader in = null;
        try {
            String urlNameString = url;
            URL realUrl = new URL(urlNameString);
            URLConnection connection = realUrl.openConnection();
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.connect();
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream(),charset));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            logger.error("发送GET请求出现异常！", e);
        }
        finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                logger.error(e2.getMessage(),e2);
            }
        }
        logger.debug("响应报文: " + result);
        return result;
    }

    public static String httpGet(String url){
        return httpGet(url,"UTF-8");
    }

    public static String httpPost(String url, String data){
        return httpPost(url, data,"UTF-8");
    }

    public static String httpPost(String url, String data,String charset){
        logger.debug("发送 http post 请求 , URL : " + url);
        logger.debug("请求体: " + data);
        OutputStream out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            URLConnection conn = realUrl.openConnection();
            conn.setRequestProperty("accept", "*/*");
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setDoOutput(true);
            conn.setDoInput(true);
            out = conn.getOutputStream();
            out.write(data.getBytes(charset));
            out.flush();
            in = new BufferedReader(
                    new InputStreamReader(conn.getInputStream(),charset));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            logger.error("发送 POST 请求出现异常！", e);
        }
        finally{
            try{
                if(out!=null){
                    out.close();
                }
                if(in!=null){
                    in.close();
                }
            }
            catch(IOException ex){
                logger.error(ex.getMessage(),ex);
            }
        }
        logger.debug("响应报文: " + result);
        return result;
    }

}

http请求工具类