Java tutorial
/* ================================================================== * RxtxDataCollectorFactory.java - Mar 24, 2012 9:04:39 PM * * Copyright 2007-2012 SolarNetwork.net Dev Team * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA * 02111-1307 USA * ================================================================== */ package net.solarnetwork.node.io.rxtx; import gnu.io.CommPortIdentifier; import gnu.io.NoSuchPortException; import gnu.io.PortInUseException; import gnu.io.SerialPort; import java.util.ArrayList; import java.util.Enumeration; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.concurrent.TimeUnit; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import net.solarnetwork.node.ConversationalDataCollector; import net.solarnetwork.node.DataCollector; import net.solarnetwork.node.DataCollectorFactory; import net.solarnetwork.node.LockTimeoutException; import net.solarnetwork.node.PortLockedConversationalDataCollector; import net.solarnetwork.node.PortLockedDataCollector; import net.solarnetwork.node.settings.SettingSpecifier; import net.solarnetwork.node.settings.SettingSpecifierProvider; import net.solarnetwork.node.settings.support.BasicTextFieldSettingSpecifier; import net.solarnetwork.node.support.DataCollectorSerialPortBeanParameters; import net.solarnetwork.node.support.SerialPortBeanParameters; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.context.MessageSource; import org.springframework.context.support.ResourceBundleMessageSource; /** * Rxtx implementation of {@link DataCollectorFactory}, exposing serial ports * for communication. * * <p> * This factory is designed to be deployed as a Configuration Admin backed * managed service factory, with one instance per serial port (identified by * {@link #getPortIdentifier()}). * </p> * * <p> * The configurable properties of this class are: * </p> * * <dl class="class-properties"> * <dt>portIdentifier</dt> * <dd>The port identifier to use for all serial communication.</dd> * <dt>groupUID</dt> * <dd>The service group to use. Defaults to <em>null</em>.</dd> * </dl> * * @author matt * @version 1.1 */ public class RxtxDataCollectorFactory implements DataCollectorFactory<SerialPortBeanParameters>, SettingSpecifierProvider { /** The default value for the {@code portIdentifier} property. */ public static final String DEFAULT_PORT_IDENTIFIER = "/dev/ttyUSB0"; private static final Map<String, Lock> PORT_LOCKS = new HashMap<String, Lock>(3); private static final Object MONITOR = new Object(); private static MessageSource MESSAGE_SOURCE; private final Logger log = LoggerFactory.getLogger(getClass()); private String portIdentifier = DEFAULT_PORT_IDENTIFIER; private long timeout = 50L; private TimeUnit unit = TimeUnit.SECONDS; private String groupUID = null; @Override public String getUID() { return portIdentifier; } @Override public String getGroupUID() { return groupUID; } private Lock acquireLock() throws LockTimeoutException { log.debug("Acquiring lock on port {}; waiting at most {} {}", new Object[] { portIdentifier, timeout, unit }); synchronized (PORT_LOCKS) { if (!PORT_LOCKS.containsKey(portIdentifier)) { PORT_LOCKS.put(portIdentifier, new ReentrantLock(true)); } Lock lock = PORT_LOCKS.get(portIdentifier); try { if (lock.tryLock(timeout, unit)) { log.debug("Acquired port {} lock", portIdentifier); return lock; } log.debug("Timeout acquiring port {} lock", portIdentifier); } catch (InterruptedException e) { log.debug("Interrupted waiting for port {} lock", portIdentifier); } } throw new LockTimeoutException("Could not acquire port " + portIdentifier + " lock"); } @Override public DataCollector getDataCollectorInstance(SerialPortBeanParameters params) { Lock lock = acquireLock(); try { CommPortIdentifier portId = getCommPortIdentifier(); // establish the serial port connection SerialPort port = (SerialPort) portId.open(params.getCommPortAppName(), 2000); AbstractSerialPortDataCollector obj; if (params instanceof DataCollectorSerialPortBeanParameters) { DataCollectorSerialPortBeanParameters dcParams = (DataCollectorSerialPortBeanParameters) params; if (dcParams.getMagicEOF() != null) { obj = new SerialPortVariableDataCollector(port, dcParams.getBufferSize(), dcParams.getMagic(), dcParams.getMagicEOF(), dcParams.getMaxWait()); } else { obj = new SerialPortDataCollector(port, dcParams.getBufferSize(), dcParams.getMagic(), dcParams.getReadSize(), dcParams.getMaxWait()); } } else { obj = new SerialPortDataCollector(port); } setupSerialPortSupport(obj, params); if (params instanceof DataCollectorSerialPortBeanParameters) { DataCollectorSerialPortBeanParameters dcParams = (DataCollectorSerialPortBeanParameters) params; obj.setToggleDtr(dcParams.isToggleDtr()); obj.setToggleRts(dcParams.isToggleRts()); } return new PortLockedDataCollector(obj, portId.getName(), lock); } catch (PortInUseException e) { lock.unlock(); throw new RuntimeException(e); } catch (RuntimeException e) { lock.unlock(); throw e; } } @Override public ConversationalDataCollector getConversationalDataCollectorInstance(SerialPortBeanParameters params) { Lock lock = acquireLock(); try { CommPortIdentifier portId = getCommPortIdentifier(); // establish the serial port connection SerialPort port = (SerialPort) portId.open(params.getCommPortAppName(), 2000); SerialPortConversationalDataCollector obj = new SerialPortConversationalDataCollector(port, params.getMaxWait()); setupSerialPortSupport(obj, params); return new PortLockedConversationalDataCollector(obj, portId.getName(), lock); } catch (PortInUseException e) { lock.unlock(); throw new RuntimeException(e); } catch (IllegalArgumentException e) { lock.unlock(); throw new RuntimeException(e); } catch (RuntimeException e) { lock.unlock(); throw e; } } @Override public String getSettingUID() { return "net.solarnetwork.node.io.rxtx"; } @Override public String getDisplayName() { return "Serial Port"; } @Override public List<SettingSpecifier> getSettingSpecifiers() { return getDefaultSettingSpecifiers(); } @Override public MessageSource getMessageSource() { synchronized (MONITOR) { if (MESSAGE_SOURCE == null) { ResourceBundleMessageSource source = new ResourceBundleMessageSource(); source.setBundleClassLoader(getClass().getClassLoader()); source.setBasename(getClass().getName()); MESSAGE_SOURCE = source; } } return MESSAGE_SOURCE; } public static List<SettingSpecifier> getDefaultSettingSpecifiers() { List<SettingSpecifier> results = new ArrayList<SettingSpecifier>(2); RxtxDataCollectorFactory defaults = new RxtxDataCollectorFactory(); results.add(new BasicTextFieldSettingSpecifier("portIdentifier", defaults.portIdentifier)); results.add(new BasicTextFieldSettingSpecifier("groupUID", defaults.groupUID)); results.add(new BasicTextFieldSettingSpecifier("timeout", String.valueOf(defaults.timeout))); return results; } /** * Configure base properties on a {@link SerialPortSupport} instance. * * @param obj * the object to configure * @param params * the parameters to copy */ private void setupSerialPortSupport(SerialPortSupport obj, SerialPortBeanParameters params) { obj.setBaud(params.getBaud()); obj.setDataBits(params.getDataBits()); obj.setStopBits(params.getStopBits()); obj.setParity(params.getParity()); obj.setFlowControl(params.getFlowControl()); obj.setReceiveFraming(params.getReceiveFraming()); obj.setReceiveThreshold(params.getReceiveThreshold()); obj.setReceiveTimeout(params.getReceiveTimeout()); obj.setDtrFlag(params.getDtrFlag()); obj.setRtsFlag(params.getRtsFlag()); } /** * Locate the {@link CommPortIdentifier} for the configured * {@link #getSerialPort()} value. * * <p> * This method will throw a RuntimeException if the port is not found. * </p> * * @return the CommPortIdentifier */ @SuppressWarnings("unchecked") private CommPortIdentifier getCommPortIdentifier() { // first try directly CommPortIdentifier commPortId = null; try { commPortId = CommPortIdentifier.getPortIdentifier(this.portIdentifier); if (commPortId != null) { log.debug("Found port identifier: {}", this.portIdentifier); return commPortId; } } catch (NoSuchPortException e) { log.debug("Port {} not found, inspecting available ports...", this.portIdentifier); } Enumeration<CommPortIdentifier> portIdentifiers = CommPortIdentifier.getPortIdentifiers(); List<String> foundNames = new ArrayList<String>(5); while (portIdentifiers.hasMoreElements()) { commPortId = portIdentifiers.nextElement(); log.trace("Inspecting available port identifier: {}", commPortId.getName()); foundNames.add(commPortId.getName()); if (commPortId.getPortType() == CommPortIdentifier.PORT_SERIAL && this.portIdentifier.equals(commPortId.getName())) { log.debug("Found port identifier: {}", this.portIdentifier); break; } } if (commPortId == null) { throw new RuntimeException("Couldn't find port identifier for [" + this.portIdentifier + "]; available ports: " + foundNames); } return commPortId; } public String getPortIdentifier() { return portIdentifier; } public void setPortIdentifier(String portIdentifier) { this.portIdentifier = portIdentifier; } public long getTimeout() { return timeout; } public void setTimeout(long timeout) { this.timeout = timeout; } public TimeUnit getUnit() { return unit; } public void setUnit(TimeUnit unit) { this.unit = unit; } public void setGroupUID(String groupUID) { this.groupUID = groupUID; } }