我想在JAVA中编写一个简单的服务器和客户端，通过蓝牙交换字符串（我想将字符串从笔记本电脑A发送到都具有Windows 7 64位的笔记本电脑B）。经过一番谷歌搜索后，我发现了bluecove java库。根据示例here
我为我的服务器编写了这段代码，它的运行没有问题，但是客户端有问题。当我想运行客户端时，出现此错误
Winsock上的BlueCove版本2.1.1-SNAPSHOT
java.lang.ClassCastException：com.intel.bluetooth.BluetoothRFCommConnectionNotifier无法转换为javax.microedition.io.StreamConnection
在bluetooch.Main.main（Main.java:84）
这是我的服务器：
package MainPackage;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import javax.bluetooth.*;
import javax.microedition.io.*;
//Class that implements an SPP Server which accepts single line of
// message from an SPP client and sends a single line of response to the
//client
public class BluetoothServer {
//start server
private void startServer() throws IOException{
//Create a UUID for SPP
UUID uuid = new UUID("1101", true);
//Create the servicve url
String connectionString = "btspp://localhost:" + uuid +";name=Sample SPP Server";
//open server url
StreamConnectionNotifier streamConnNotifier = (StreamConnectionNotifier)Connector.open( connectionString );
//Wait for client connection
System.out.println("\nServer Started. Waiting for clients to connect...");
StreamConnection connection = streamConnNotifier.acceptAndOpen();
RemoteDevice dev = RemoteDevice.getRemoteDevice(connection);
System.out.println("Remote device address: "+dev.getBluetoothAddress());
System.out.println("Remote device name: "+dev.getFriendlyName(true));
//read string from spp client
InputStream inStream=connection.openInputStream();
BufferedReader bReader=new BufferedReader(new InputStreamReader(inStream));
String lineRead=bReader.readLine();
System.out.println(lineRead);
//send response to spp client
OutputStream outStream=connection.openOutputStream();
PrintWriter pWriter=new PrintWriter(new OutputStreamWriter(outStream));
pWriter.write("Response String from SPP Server\r\n");
pWriter.flush();
pWriter.close();
streamConnNotifier.close();
}
public static void main(String[] args) {
try {
//display local device address and name
LocalDevice localDevice = LocalDevice.getLocalDevice();
System.out.println("Address: "+localDevice.getBluetoothAddress());
System.out.println("Name: "+localDevice.getFriendlyName());
System.out.println("localDevice.getDiscoverable() " + localDevice.getDiscoverable());
System.out.println("bluetooth is discoverable " + localDevice.setDiscoverable(DiscoveryAgent.LIAC));
BluetoothServer sampleSPPServer=new BluetoothServer();
sampleSPPServer.startServer();
} catch (Exception e) {
e.printStackTrace();
}
}
}
这是客户
package bluetooch;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.Scanner;
import java.util.Vector;
import javax.microedition.io.Connector;
import javax.microedition.io.StreamConnection;
public class Main {
public static final Vector devicesDiscovered = new Vector();
public static void main(String[] args){
try {
StreamConnection streamConnection = (StreamConnection)Connector.open("btspp://localhost:" + "1101" +";name=Sample SPP Server");
//send string
OutputStream outStream = streamConnection.openOutputStream();
PrintWriter pWriter=new PrintWriter(new OutputStreamWriter(outStream));
pWriter.write("Test String from SPP Client\r\n");
pWriter.flush();
//read response
InputStream inStream=streamConnection.openInputStream();
BufferedReader bReader2=new BufferedReader(new InputStreamReader(inStream));
String lineRead=bReader2.readLine();
System.out.println(lineRead);
Scanner keyboard = new Scanner(System.in);
System.out.println("enter an integer");
int myint = keyboard.nextInt();
} catch (Exception e) {
System.out.println("Error Occured! below is the message\r\n" + e.getMessage());
}
}
}
关于这个问题有什么想法吗？
最佳答案
好吧，消息说明了一切。
您正在将Connection返回的Connector.open()强制转换为StreamConnection。
但是返回的连接不是StreamConnection的实例。它是com.intel.bluetooth.BluetoothRFCommConnectionNotifier的一个实例，如果您阅读javadoc或源代码，它将实现StreamConnectionNotifier，而不是StreamConnection。