海豚的成长日记 2020-05-04
蓝牙作为一种短距离无线通讯技术,越来越融合到我们的生活当中,软件开发也是随处可见。本文介绍的是PC端与其他蓝牙设备建立通讯的一个案例。
蓝牙客户端,即是请求连接的一端,搜索会发现可连接的蓝牙设备名称。
蓝牙服务端,提供服务的一端。往往生活中使用到的蓝牙(比如手机是个双重角色),又是客户端又是服务端。
蓝牙通信的原理
蓝牙技术规定每一对设备之间进行蓝牙通讯时,必须一个为主角色,另一为从角色,才能进行通信,通信时,必须由主端进行查找,发起配对,建链成功后,双方即可收发数据。蓝牙主端设备发起呼叫,首先是查找,找出周围处于可被查找的蓝牙设备。主端设备找到从端蓝牙设备后,与从端蓝牙设备进行配对,此时需要输入从端设备的PIN码,也有设备不需要输入PIN码。
首先,在PC端实现蓝牙java并没有提供官方jar包,本文使用的是一个第三方库。需要手动导入到maven仓库,
不会导仓库的请参考https://www.cnblogs.com/zeussbook/p/9930679.htm。
第三方jar包下载地址:https://sourceforge.net/projects/bluecove/files/BlueCove/2.1.0/bluecove-2.1.0.jar/download
2.1蓝牙服务端
package com.shunyutong.test.bluetooth; import javax.bluetooth.DiscoveryAgent; import javax.bluetooth.LocalDevice; import javax.microedition.io.Connector; import javax.microedition.io.StreamConnection; import javax.microedition.io.StreamConnectionNotifier; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; /** * @Auther: lanhaifeng * @Date: 2020/5/4 0004 16:28 * @Description: 蓝牙服务端 * @statement: */ public class BluetoothServer implements Runnable{ //本机蓝牙设备 private LocalDevice local = null; // 流连接 private StreamConnection streamConnection = null; // 输入流 private InputStream inputStream; private OutputStream outputStream; //接入通知 private StreamConnectionNotifier notifier; //基于缓存的线程池 private final static ExecutorService service = Executors.newCachedThreadPool(); public String serverName; public String serverUUID; private OnServerListener mServerListener; /** * 服务监听接口 */ public interface OnServerListener { void onConnected(InputStream inputStream, OutputStream outputStream); void onDisconnected(); void onClose(); } /** * 蓝牙服务有参构造函数 * @param serverUUID id * @param serverName 名称 */ public BluetoothServer(String serverUUID, String serverName) { this.serverUUID = serverUUID; this.serverName = serverName; } /** * 启动 */ public void start() { try { local = LocalDevice.getLocalDevice(); if (!local.setDiscoverable(DiscoveryAgent.GIAC)) System.out.println("请将蓝牙设置为可被发现"); //作为服务端,被请求 String url = "btspp://localhost:" + serverUUID+ ";name="+serverName; notifier = (StreamConnectionNotifier) Connector.open(url); service.submit(this); } catch (IOException e) { System.out.println(e.getMessage());; } } /** * 重写run() */ @Override public void run() { try { streamConnection = notifier.acceptAndOpen(); //阻塞的,等待设备连接 inputStream = streamConnection.openInputStream(); outputStream = streamConnection.openOutputStream(); if (mServerListener != null) { mServerListener.onConnected(inputStream, outputStream); } } catch (IOException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } finally { } } public OnServerListener getServerListener() { return mServerListener; } public void setServerListener(OnServerListener mServerListener) { this.mServerListener = mServerListener; } }
2.2蓝牙客户端
package com.shunyutong.test.bluetooth; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.Iterator; import java.util.Set; import javax.bluetooth.RemoteDevice; import javax.microedition.io.Connector; import javax.microedition.io.StreamConnection; /** * @Auther: lanhaifeng * @Date: 2020/5/4 0004 15:37 * @Description:蓝牙客户端类 * @statement: */ public class BluetoothClient { private StreamConnection streamConnection;//流连接 private OnDiscoverListener onDiscoverListener = null;//发现监听 private OnClientListener onClientListener = null;//客户端监听 /** * 客户端监听 */ public interface OnClientListener { void onConnected(InputStream inputStream, OutputStream outputStream); void onConnectionFailed(); void onDisconnected(); void onClose(); } /** * 发现监听 */ public interface OnDiscoverListener { void onDiscover(RemoteDevice remoteDevice); } /** * 无参构造函数 */ public BluetoothClient() { } /** * 查找所有 * @throws IOException * @throws InterruptedException */ public void find() throws IOException, InterruptedException { //附近所有的蓝牙设备,必须先执行 runDiscovery Set<RemoteDevice> devicesDiscovered = RemoteDeviceDiscovery.getDevices(); Iterator<RemoteDevice> itr = devicesDiscovered.iterator(); //连接 while (itr.hasNext()) { RemoteDevice remoteDevice = itr.next(); onDiscoverListener.onDiscover(remoteDevice); } } /** * 启动连接 * @param remoteDevice * @param serviceUUID * @throws IOException * @throws InterruptedException */ public void startClient(RemoteDevice remoteDevice, String serviceUUID) throws IOException, InterruptedException { String url = RemoteDeviceDiscovery.searchService(remoteDevice, serviceUUID); streamConnection = (StreamConnection) Connector.open(url); if (this.onClientListener != null) { this.onClientListener.onConnected(streamConnection.openInputStream(), streamConnection.openOutputStream()); } } public OnDiscoverListener getOnDiscoverListener() { return onDiscoverListener; } public void setOnDiscoverListener(OnDiscoverListener onDiscoverListener) { this.onDiscoverListener = onDiscoverListener; } public OnClientListener getClientListener() { return onClientListener; } public void setClientListener(OnClientListener onClientListener) { this.onClientListener = onClientListener; } }
2.3设备查找类
package com.shunyutong.test.bluetooth; import java.io.IOException; import java.util.HashSet; import java.util.Set; import java.util.Vector; import javax.bluetooth.DataElement; import javax.bluetooth.DeviceClass; import javax.bluetooth.DiscoveryAgent; import javax.bluetooth.DiscoveryListener; import javax.bluetooth.LocalDevice; import javax.bluetooth.RemoteDevice; import javax.bluetooth.ServiceRecord; import javax.bluetooth.UUID; /** * @Auther: lanhaifeng * @Date: 2020/5/4 0004 16:07 * @Description:设备查找类 * @statement: */ public class RemoteDeviceDiscovery { public final static Set<RemoteDevice> devicesDiscovered = new HashSet<RemoteDevice>(); public final static Vector<String> serviceFound = new Vector<String>(); final static Object serviceSearchCompletedEvent = new Object(); final static Object inquiryCompletedEvent = new Object(); /** * 发现监听 */ private static DiscoveryListener listener = new DiscoveryListener() { public void inquiryCompleted(int discType) { System.out.println("#" + "搜索完成"); synchronized (inquiryCompletedEvent) { inquiryCompletedEvent.notifyAll(); } } /** * 发现设备 * @param remoteDevice * @param deviceClass */ @Override public void deviceDiscovered(RemoteDevice remoteDevice, DeviceClass deviceClass) { devicesDiscovered.add(remoteDevice); try { System.out.println("#发现设备" + remoteDevice.getFriendlyName(false)); } catch (IOException e) { e.printStackTrace(); } } /** * 发现服务 * @param transID id * @param servRecord 服务记录 */ @Override public void servicesDiscovered(int transID, ServiceRecord[] servRecord) { for (int i = 0; i < servRecord.length; i++) { String url = servRecord[i].getConnectionURL(ServiceRecord.NOAUTHENTICATE_NOENCRYPT, false); if (url == null) { continue; } serviceFound.add(url); DataElement serviceName = servRecord[i].getAttributeValue(0x0100); if (serviceName != null) { System.out.println("service " + serviceName.getValue() + " found " + url); } else { System.out.println("service found " + url); } } System.out.println("#" + "servicesDiscovered"); } /** * 服务搜索已完成 * @param arg0 * @param arg1 */ @Override public void serviceSearchCompleted(int arg0, int arg1) { System.out.println("#" + "serviceSearchCompleted"); synchronized(serviceSearchCompletedEvent){ serviceSearchCompletedEvent.notifyAll(); } } }; /** * 查找设备 * @throws IOException * @throws InterruptedException */ private static void findDevices() throws IOException, InterruptedException { devicesDiscovered.clear(); synchronized (inquiryCompletedEvent) { LocalDevice ld = LocalDevice.getLocalDevice(); System.out.println("#本机蓝牙名称:" + ld.getFriendlyName()); boolean started = LocalDevice.getLocalDevice().getDiscoveryAgent().startInquiry(DiscoveryAgent.GIAC,listener); if (started) { System.out.println("#" + "等待搜索完成..."); inquiryCompletedEvent.wait(); LocalDevice.getLocalDevice().getDiscoveryAgent().cancelInquiry(listener); System.out.println("#发现设备数量:" + devicesDiscovered.size()); } } } /** * 获取设备 * @return * @throws IOException * @throws InterruptedException */ public static Set<RemoteDevice> getDevices() throws IOException, InterruptedException { findDevices(); return devicesDiscovered; } /** * 查找服务 * @param btDevice * @param serviceUUID * @return * @throws IOException * @throws InterruptedException */ public static String searchService(RemoteDevice btDevice, String serviceUUID) throws IOException, InterruptedException { UUID[] searchUuidSet = new UUID[] { new UUID(serviceUUID, false) }; int[] attrIDs = new int[] { 0x0100 // Service name }; synchronized(serviceSearchCompletedEvent) { System.out.println("search services on " + btDevice.getBluetoothAddress() + " " + btDevice.getFriendlyName(false)); LocalDevice.getLocalDevice().getDiscoveryAgent().searchServices(attrIDs, searchUuidSet, btDevice, listener); serviceSearchCompletedEvent.wait(); } if (serviceFound.size() > 0) { return serviceFound.elementAt(0); } else { return ""; } } }
2.4蓝牙服务端使用
package com.shunyutong.test.bluetoothService; import com.shunyutong.test.bluetooth.BluetoothServer; import java.io.InputStream; import java.io.OutputStream; /** * @Auther: lanhaifeng * @Date: 2020/5/4 0004 16:47 * @Description: 蓝牙服务端通信业务 * @statement: */ public class BluetoothServerService { public static void main(String[] argv) { final String serverName = "Bluetooth Server Test"; final String serverUUID = "1000110100001000800000805F9B34FB"; //根据需要自定义 BluetoothServer server = new BluetoothServer(serverUUID, serverName); server.setServerListener(new BluetoothServer.OnServerListener() { @Override public void onConnected(InputStream inputStream, OutputStream outputStream) { System.out.printf("Connected"); //添加通信代码 System.out.println(server.serverName); System.out.println(server.serverUUID); } @Override public void onDisconnected() { } @Override public void onClose() { } }); server.start(); } }
2.5蓝牙客户端使用
package com.shunyutong.test.bluetoothService; import com.shunyutong.test.bluetooth.BluetoothClient; import javax.bluetooth.RemoteDevice; import javax.microedition.io.ConnectionNotFoundException; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.Vector; /** * @Auther: lanhaifeng * @Date: 2020/5/4 0004 16:51 * @Description: 蓝牙客户端业务类 * @statement: */ public class BluetoothClientService { public static void main(String[] argv) { final String serverUUID = "1000110100001000800000805F9B34FB"; //需要与服务端相同 BluetoothClient client = new BluetoothClient(); Vector<RemoteDevice> remoteDevices = new Vector<>(); client.setOnDiscoverListener(new BluetoothClient.OnDiscoverListener() { @Override public void onDiscover(RemoteDevice remoteDevice) { remoteDevices.add(remoteDevice); } }); client.setClientListener(new BluetoothClient.OnClientListener() { @Override public void onConnected(InputStream inputStream, OutputStream outputStream) { System.out.printf("Connected"); //添加通信代码 } @Override public void onConnectionFailed() { System.out.printf("Connection failed"); } @Override public void onDisconnected() { } @Override public void onClose() { } }); try { client.find(); if (remoteDevices.size() > 0 ) { client.startClient(remoteDevices.firstElement(), serverUUID); } }catch (InterruptedException e) { e.printStackTrace(); }catch (ConnectionNotFoundException e){ System.out.println("当前蓝牙不在线"); e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); } } }
测试效果