SappBindingConfigUtils.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.sapp.internal.configs;

/**
 * This is a helper class for generic binding helper methods
 *
 * @author Paolo Denti
 * @since 1.8.0
 *
 */
public class SappBindingConfigUtils {

    public static final String WORD_MASK_U = "*";
    public static final String WORD_MASK_S = "+";
    public static final String LOW_MASK_U = "L";
    public static final String LOW_MASK_S = "L+";
    public static final String HIGH_MASK_U = "H";
    public static final String HIGH_MASK_S = "H+";

    /**
     * mask the value against the subAddress
     * 
     * @param subAddress
     *            subAddress (*, H, L, bit)
     * @param value
     *            value to be masked against the subAddress
     */
    public static int maskWithSubAddress(String subAddress, int value) {

        if (subAddress.equals(WORD_MASK_U) || subAddress.equals(WORD_MASK_S)) {
            return value & 0xFFFF;
        } else if (subAddress.equals(LOW_MASK_U) || subAddress.equals(LOW_MASK_S)) {
            return (value & 0x00FF);
        } else if (subAddress.equals(HIGH_MASK_U) || subAddress.equals(HIGH_MASK_S)) {
            return ((value >> 8) & 0x00FF);
        } else {
            int shift = Integer.parseInt(subAddress);
            return ((0x0001 << (shift - 1) & value) >> (shift - 1));
        }
    }

    /**
     * mask the value against the subAddress and overwrite the previous value with the masked value
     * 
     * @param subAddress
     *            subAddress (*, H, L, bit)
     * @param newValue
     *            value to be masked against the subAddress
     * @param previousValue
     *            previous word value to be masked against the new masked value
     */
    public static int maskWithSubAddressAndSet(String subAddress, int newValue, int previousValue) {

        if (subAddress.equals(WORD_MASK_U) || subAddress.equals(WORD_MASK_S)) {
            return newValue & 0xFFFF;
        } else if (subAddress.equals(LOW_MASK_U) || subAddress.equals(LOW_MASK_S)) {
            return (newValue & 0x00FF) | (previousValue & 0xFF00);
        } else if (subAddress.equals(HIGH_MASK_U) || subAddress.equals(HIGH_MASK_S)) {
            return ((newValue << 8) & 0xFF00) | (previousValue & 0x00FF);
        } else {
            int shift = Integer.parseInt(subAddress);
            if ((newValue & 0x0001) != 0) {
                return previousValue | (1 << (shift - 1));
            } else {
                return previousValue & ~(1 << (shift - 1));
            }
        }
    }
}