AbstractNumberTypeConverter.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.homematic.internal.converter.state;

import java.math.BigDecimal;

import org.openhab.binding.homematic.internal.model.HmValueItem;
import org.openhab.core.library.types.DecimalType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Baseclass for all number converters with common methods.
 *
 * @author Gerhard Riegler
 * @since 1.5.0
 */
public abstract class AbstractNumberTypeConverter<T extends DecimalType> extends AbstractTypeConverter<T> {
    private static final Logger logger = LoggerFactory.getLogger(AbstractNumberTypeConverter.class);

    /**
     * Subclasses must implement this method to create a number type from the value.
     */
    protected abstract T createType(BigDecimal value);

    /**
     * {@inheritDoc}
     */
    @Override
    protected Boolean toBoolean(T type, HmValueItem hmValueItem) {
        return new Boolean(toNumber(type, hmValueItem).doubleValue() == hmValueItem.getMaxValue().doubleValue());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected Number toNumber(T type, HmValueItem hmValueItem) {
        if (hmValueItem.isIntegerValue()) {
            return type.intValue();
        }
        return round(type.doubleValue()).doubleValue();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected String toString(T type, HmValueItem hmValueItem) {
        return toNumber(type, hmValueItem).toString();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected T fromBoolean(HmValueItem hmValueItem) {
        if (Boolean.TRUE.equals(hmValueItem.getValue())) {
            return createType(round(hmValueItem.getMaxValue().doubleValue()));
        }
        return createType(round(hmValueItem.getMinValue().doubleValue()));
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected T fromNumber(HmValueItem hmValueItem) {
        Double number = ((Number) hmValueItem.getValue()).doubleValue();
        if (hmValueItem.isIntegerValue()) {
            return createType(new BigDecimal(number.intValue()));
        }
        return createType(round(number));
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected T fromString(HmValueItem hmValueItem) {
        return createTypeFromString(hmValueItem.getValue().toString());
    }

    private T createTypeFromString(String value) {
        try {
            return createType(new BigDecimal(value));
        } catch (NumberFormatException ex) {
            logger.warn("Can't convert string value '{}' to a number, returning 0", value);
            return createType(new BigDecimal(0));
        }
    }

}