我正在尝试用Java编写一个简单的脚本来从蓝牙设备读取数据,该数据会发出恒定的数据流。我知道设备正在运行,因为我可以使用Python解决我的问题,但我最终想要使用Java。
我有一些示例代码,但它依赖于read命令。
// Ref http://homepages.ius.edu/rwisman/C490/html/JavaandBluetooth.htm
import java.io.*;
import javax.microedition.io.*;
//import javax.bluetooth.*;
public class RFCOMMClient {
public static void main(String args[]) {
try {
StreamConnection conn = (StreamConnection) Connector.open(
"btspp://00078093523B:2", Connector.READ, true);
InputStream is = conn.openInputStream();
byte buffer[] = new byte[8];
try {
int bytes_read = is.read(buffer, 0, 8);
String received = new String(buffer, 0, bytes_read);
System.out.println("received: " + received);
} catch (IOException e) {
System.out.println(" FAIL");
System.err.print(e.toString());
}
conn.close();
} catch (IOException e) {
System.err.print(e.toString());
}
}
}
请注意,问题似乎是read()调用认为没有可用数据。然而,蓝牙设备不断地吐出数据(它是传感器)。这是我的Python代码,它可以工作:
In [1]: import bluetooth
In [2]: address = "00:07:80:93:52:3B"
In [3]: s = bluetooth.BluetoothSocket(bluetooth.RFCOMM)
In [4]: s.connect((address,1))
In [5]: s.recv(1024)
Out[5]: '<CONFIDENTIALDATAREMOVED>'
请帮忙,
谢谢!
答案 0 :(得分:1)
读取将阻塞并等待数据;一个更好的习语就是使用available():
int bytesToRead = is.available();
if(bytesToRead > 0)
is.read(buffer, 0, bytesToRead);
else
// wait for data to become available