蓝牙ble连接报错

print_bluetooth(mac_address){
let that=this
uni.hideLoading()
let UUID = plus.android.importClass("java.util.UUID");
let uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
let device = BAdapter.getRemoteDevice(mac_address);
plus.android.importClass(device);
let bluetoothSocket = device.createInsecureRfcommSocketToServiceRecord(uuid);
plus.android.importClass(bluetoothSocket);
if (!bluetoothSocket.isConnected()) {
console.log('检测到设备未连接，尝试连接....');
bluetoothSocket.connect();
}

            console.log('设备已连接');  

            if (bluetoothSocket.isConnected()) {  
                var outputStream = bluetoothSocket.getOutputStream();  
                plus.android.importClass(outputStream);  
                var string = "打印测试\r\n";  
                var bytes = plus.android.invoke(string, 'getBytes', 'gbk');  
                outputStream.write(bytes);  
                outputStream.flush();  
                device = null //这里关键  
                bluetoothSocket.close(); //必须关闭蓝牙连接否则意外断开的话打印错误  

            }  
        },  

直接连接报错Uncaught java.io.IOException: read failed, socket might closed or timeout, read ret: -1;at android.bluetooth.BluetoothSocket.connect at index.html:1