java UDP的一个封装

package cn.com.sany.udp; import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; import java.net.SocketException; import java.text.SimpleDateFormat; import java.util.Date; /** * * 工具类, 主动和被动发送消息所需要用到的公共方法 * 避免维护重复的代码 * * */ public class UDPTool { /** * 得到当前的时间 * * @return */ public static String getCurrentTime() { SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH:mm:ss "); Date curDate = new Date(System.currentTimeMillis());// 获取当前时间 String str = formatter.format(curDate); return str; } public static String toHexString(byte[] bufIn, int bytesLen) { if (bytesLen == -1) { bytesLen = bufIn.length; } StringBuffer buff = new StringBuffer(); for (int i = 0; i < bytesLen; i++) { buff.append(Integer.toHexString((bufIn[i]) & 0xFF) + " "); } return buff.toString(); } /** * 发送数据包 * */ public static void sendData(String ip, int port, byte[] data, DatagramSocket socket) { try { System.out.println("数据发送!"); DatagramPacket packet = new DatagramPacket(data, data.length, InetAddress.getByName(ip), port); socket.send(packet); } catch (SocketException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } /** * 接收数据帧, 在发送端口上面进行接收 */ public static void receiveData(DatagramSocket socket) { try { byte[] buffer = new byte[65508]; DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length); System.out.println("---接收数据--"); socket.receive(packet); byte[] data = packet.getData(); int len = packet.getLength(); String hexString = UDPTool.toHexString(data, len); String time = UDPTool.getCurrentTime(); System.out.println("---接收到服务端的时间和数据(16)--" + time + "内容:" + hexString); } catch (SocketException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }