CommandProvider.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.plcbus.internal.protocol;

import java.util.HashMap;

import org.openhab.binding.plcbus.internal.protocol.commands.Bright;
import org.openhab.binding.plcbus.internal.protocol.commands.Dim;
import org.openhab.binding.plcbus.internal.protocol.commands.FadeStop;
import org.openhab.binding.plcbus.internal.protocol.commands.StatusOff;
import org.openhab.binding.plcbus.internal.protocol.commands.StatusOn;
import org.openhab.binding.plcbus.internal.protocol.commands.StatusRequest;
import org.openhab.binding.plcbus.internal.protocol.commands.UnitOff;
import org.openhab.binding.plcbus.internal.protocol.commands.UnitOn;

/**
 * Provider for creating PLCBusCommmands by Commandbyte
 *
 * @author Robin Lenz
 * @since 1.0.0
 */
public class CommandProvider {

    private HashMap<Byte, Class<? extends Command>> commands;

    /**
     * Create a new CommandProvider
     */
    public CommandProvider() {
        commands = new HashMap<Byte, Class<? extends Command>>();
        init();
    }

    /**
     * Create the Command for commandByte
     * 
     * @param commandByte
     *            of Command
     * @return created Command
     */
    public Command getCommandBy(byte commandByte) {
        if (!commands.containsKey(commandByte)) {
            return null;
        }

        Class<? extends Command> commandClass = commands.get(commandByte);

        return createCommandFrom(commandClass);
    }

    private void init() {
        add(UnitOn.class);
        add(UnitOff.class);
        add(Bright.class);
        add(Dim.class);
        add(FadeStop.class);
        add(StatusRequest.class);
        add(StatusOn.class);
        add(StatusOff.class);
    }

    private void add(Class<? extends Command> type) {
        Command command = createCommandFrom(type);

        if (command != null) {
            commands.put(command.getId(), type);
        }
    }

    private Command createCommandFrom(Class<? extends Command> type) {
        try {
            return type.getConstructor(null).newInstance(null);
        } catch (Exception e) {
            return null;
        }
    }

}