发送 GET 和 POST请求
/** *@param url 发送请求的url *@param param 请求参数 请求参数应该是 name=xx&pass=xxxx */public static String sendGet(String url,String param){String result="";BufferedReader bfr=null;try {String urlName=url+"?"+param;URL realUrl=new URL(urlName);URLConnection conn=realUrl.openConnection();conn.setRequestProperty("accept", "*/*");conn.setRequestProperty("connection", "Keep-Alive");conn.setRequestProperty("user-age", "Mozilla/4.0 (compatible;MSIE 6.0;Window NT 5.1;SV1)");//建立实际的连接conn.connect();Map<String,List<String>> map=conn.getHeaderFields();//遍历所有的响应头字段for (String key: map.keySet()) {System.out.println(key+"--->"+map.get(key));}//定义 BufferedRead输入流来读取URL的响应bfr=new BufferedReader(new InputStreamReader(conn.getInputStream()));String line;while((line=bfr.readLine())!=null){result+="\n"+line;}} catch (Exception e) {System.out.print("发送GET请求出现异常:"+e);e.printStackTrace();}finally{try {if(bfr!=null)bfr.close();} catch (IOException ex) {ex.printStackTrace();}}return result;}/** *@param url 发送请求的url *@param param 请求参数 请求参数应该是 name=xx&pass=xxxx */public 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();//设置通用的请求属性conn.setRequestProperty("accept", "*/*");conn.setRequestProperty("connection", "Keep-Alive");conn.setRequestProperty("user-age", "Mozilla/4.0 (compatible;MSIE 6.0;Window NT 5.1;SV1)");//发送POST请求必须设置如下两行conn.setDoOutput(true);conn.setDoInput(true);out=new PrintWriter(conn.getOutputStream());out.print(param);out.flush();in=new BufferedReader(new InputStreamReader(conn.getInputStream()));String line;while((line=in.readLine())!=null){result+="\n"+line;}} catch (Exception e) {System.out.println("发送POST请求出现异常:"+e);e.printStackTrace();}finally{try {if(out!=null)out.close();if(in!=null)in.close();} catch (IOException ex) {ex.printStackTrace();}}return result;}