import org.ros.node.NodeMain; //导入依赖的package包/类
/**
 * Called when a USB device has been disconnected
 */
private void onDeviceDetached(UsbDevice device) {
    NodeMain[] nodeMains = mUsbNodes.get(device);
    if (nodeMains != null) {
        for (NodeMain nodeMain : nodeMains) {
            // Shutdown this node, considering it has been unplugged
            mLog.info("Device for node unplugged, shutting down");
            mNodeMainExecutor.shutdownNodeMain(nodeMain);
        }
    } else {
        mLog.info("USB device unplugged but no corresponding node found");
    }
}
 

import org.ros.node.NodeMain; //导入依赖的package包/类
@Override
public NodeMain[] startNodes(UsbDevice baseUsbDevice, UsbManager usbManager) throws Exception {
    if(baseUsbDevice == null) {
        throw new Exception("null USB device provided");
    }
    log.info("Starting base node");

    // Wrap the UsbDevice in the HoHo Driver
    UsbSerialDriver driver = serialDriverForDevice(baseUsbDevice, usbManager);
    UsbDeviceConnection connection = serialConnectionForDevice(usbManager, driver);

    if (connection == null) {
        throw new Exception("No USB connection available to initialize device");
    }

    UsbSerialPort port = serialPortForDevice(driver);

    // Choose the appropriate BaseDevice implementation for the particular
    // robot base, using the corresponding subclass
    BaseDevice baseDevice = getBaseDevice(port, connection);

    // Create the ROS nodes
    log.info("Create base controller node");
    mBaseControllerNode = new BaseControllerNode(baseDevice, "/cmd_vel");
    NodeConfiguration baseControllerNodeConf = NodeConfiguration.newPublic(mRosHostname);
    baseControllerNodeConf.setNodeName(GraphName.of("base_controller"));
    baseControllerNodeConf.setMasterUri(mRosMasterUri);
    mNodeMainExecutor.execute(mBaseControllerNode, baseControllerNodeConf);

    mBatteryPublisherNode = new RobotBatteryPublisherNode(baseDevice);
    NodeConfiguration batteryPublisherConf = NodeConfiguration.newPublic(mRosHostname);
    batteryPublisherConf.setNodeName(mBaseControllerNode.getDefaultNodeName());
    batteryPublisherConf.setMasterUri(mRosMasterUri);
    mNodeMainExecutor.execute(mBatteryPublisherNode, batteryPublisherConf);

    return new NodeMain[]{mBaseControllerNode, mBaseOdomPublisher};
}
 

import org.ros.node.NodeMain; //导入依赖的package包/类
@Override
protected void init(NodeMainExecutor nodeMainExecutor) {
    NodeMain node = new SimplePublisherNode();

    NodeConfiguration nodeConfiguration = NodeConfiguration.newPublic(InetAddressFactory.newNonLoopback().getHostAddress());
    nodeConfiguration.setMasterUri(getMasterUri());

    nodeMainExecutor.execute(node, nodeConfiguration);
}
 

import org.ros.node.NodeMain; //导入依赖的package包/类
@Override
public void execute(NodeMain nodeMain, NodeConfiguration nodeConfiguration,
                    Collection<NodeListener> nodeListeneners) {
  nodeMainExecutor.execute(nodeMain, nodeConfiguration, nodeListeneners);
}
 

import org.ros.node.NodeMain; //导入依赖的package包/类
@Override
public void shutdownNodeMain(NodeMain nodeMain) {
  nodeMainExecutor.shutdownNodeMain(nodeMain);
}
 

import org.ros.node.NodeMain; //导入依赖的package包/类
public abstract NodeMain[] startNodes(UsbDevice device, UsbManager usbManager) throws Exception;