Java发送Http请求（Get和Post）

public class NetRequestUtil {/** * 发送http的get和post请求 ,当请求为get时，param格式为paramName1=value1¶mName2=value2;当请求为post时，param格式为json * @param url * @param param * @param method * @return */public static String sendHttpRequest(String url,String method,String param){PrintWriter out = null;        BufferedReader in = null;        String result = "";        URLConnection conn=null;try {if("post".equals(method.toLowerCase())){URL post_url=new URL(url);conn=post_url.openConnection();conn.setRequestProperty("content-Type","application/json");conn.setRequestProperty("chartset", "utf-8");conn.setDoOutput(true);conn.setDoInput(true);out=new PrintWriter(conn.getOutputStream());out.print(param);out.flush();}else{URL post_url=new URL(url+"?"+param);conn=post_url.openConnection();conn.setRequestProperty("chartset", "utf-8");}in = new BufferedReader(new InputStreamReader(conn.getInputStream()));String line;            while ((line = in.readLine()) != null) {                result += line;            }} catch (Exception e) {e.printStackTrace();} finally {try {if(out != null)out.close();if(in != null)in.close();} catch (IOException e) {e.printStackTrace();}}return result;}}