Java tutorial
/* * Copyright 2018 Anton Tananaev (anton@traccar.org) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.traccar.protocol; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import org.traccar.BaseProtocolDecoder; import org.traccar.DeviceSession; import org.traccar.NetworkMessage; import org.traccar.Protocol; import org.traccar.helper.Parser; import org.traccar.helper.PatternBuilder; import org.traccar.helper.UnitsConverter; import org.traccar.model.CellTower; import org.traccar.model.Network; import org.traccar.model.Position; import org.traccar.model.WifiAccessPoint; import java.net.SocketAddress; import java.nio.charset.StandardCharsets; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.LinkedList; import java.util.List; import java.util.regex.Pattern; public class WristbandProtocolDecoder extends BaseProtocolDecoder { public WristbandProtocolDecoder(Protocol protocol) { super(protocol); } private void sendResponse(Channel channel, String imei, String version, int type, String data) { if (channel != null) { String sentence = String.format("YX%s|%s|0|{F%02d#%s}\r\n", imei, version, type, data); ByteBuf response = Unpooled.buffer(); if (type != 91) { response.writeBytes(new byte[] { 0x00, 0x01, 0x02 }); response.writeShort(sentence.length()); } response.writeCharSequence(sentence, StandardCharsets.US_ASCII); if (type != 91) { response.writeBytes(new byte[] { (byte) 0xFF, (byte) 0xFE, (byte) 0xFC }); } channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress())); } } private static final Pattern PATTERN = new PatternBuilder().expression("..") // header .number("(d+)|") // imei .number("([vV]d+.d+)|") // version .number("d+|") // model .text("{").number("F(d+)") // function .groupBegin().text("#").expression("(.*)") // data .groupEnd("?").text("}").text("\r\n").compile(); private Position decodePosition(DeviceSession deviceSession, String sentence) throws ParseException { Position position = new Position(getProtocolName()); position.setDeviceId(deviceSession.getDeviceId()); String[] values = sentence.split(","); position.setValid(true); position.setLongitude(Double.parseDouble(values[0])); position.setLatitude(Double.parseDouble(values[1])); position.setTime(new SimpleDateFormat("yyyyMMddHHmm").parse(values[2])); position.setSpeed(UnitsConverter.knotsFromKph(Double.parseDouble(values[3]))); return position; } private Position decodeStatus(DeviceSession deviceSession, String sentence) { Position position = new Position(getProtocolName()); position.setDeviceId(deviceSession.getDeviceId()); getLastLocation(position, null); position.set(Position.KEY_BATTERY_LEVEL, Integer.parseInt(sentence.split(",")[0])); return position; } private Position decodeNetwork(DeviceSession deviceSession, String sentence, boolean wifi) { Position position = new Position(getProtocolName()); position.setDeviceId(deviceSession.getDeviceId()); getLastLocation(position, null); Network network = new Network(); String[] fragments = sentence.split("\\|"); if (wifi) { for (String item : fragments[0].split("_")) { String[] values = item.split(","); network.addWifiAccessPoint(WifiAccessPoint.from(values[0], Integer.parseInt(values[1]))); } } for (String item : fragments[wifi ? 1 : 0].split(":")) { String[] values = item.split(","); int lac = Integer.parseInt(values[0]); int mnc = Integer.parseInt(values[1]); int mcc = Integer.parseInt(values[2]); int cid = Integer.parseInt(values[3]); int rssi = Integer.parseInt(values[4]); network.addCellTower(CellTower.from(mcc, mnc, lac, cid, rssi)); } position.setNetwork(network); return position; } private List<Position> decodeMessage(Channel channel, SocketAddress remoteAddress, String sentence) throws ParseException { Parser parser = new Parser(PATTERN, sentence); if (!parser.matches()) { return null; } String imei = parser.next(); DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, imei); if (deviceSession == null) { return null; } String version = parser.next(); int type = parser.nextInt(); List<Position> positions = new LinkedList<>(); String data = parser.next(); switch (type) { case 90: sendResponse(channel, imei, version, type, getServer(channel, ',')); break; case 91: String time = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss").format(new Date()); sendResponse(channel, imei, version, type, time + "|" + getServer(channel, ',')); break; case 1: positions.add(decodeStatus(deviceSession, data)); sendResponse(channel, imei, version, type, data.split(",")[1]); break; case 2: for (String fragment : data.split("\\|")) { positions.add(decodePosition(deviceSession, fragment)); } break; case 3: case 4: positions.add(decodeNetwork(deviceSession, data, type == 3)); break; case 64: sendResponse(channel, imei, version, type, data); break; default: break; } return positions.isEmpty() ? null : positions; } @Override protected Object decode(Channel channel, SocketAddress remoteAddress, Object msg) throws Exception { ByteBuf buf = (ByteBuf) msg; buf.skipBytes(3); // header buf.readUnsignedShort(); // length String sentence = buf.toString(buf.readerIndex(), buf.readableBytes() - 3, StandardCharsets.US_ASCII); buf.skipBytes(3); // footer return decodeMessage(channel, remoteAddress, sentence); } }