package org.dcache.services.info.base;


/**
 * Extends the abstract StateValue to allow the storage of 64-bit signed numbers
 * within dCache state.
 *
 * @author Paul Millar <paul.millar@desy.de>
 */
public class IntegerStateValue extends StateValue
{
    private final long _storage;

    /**
     * Create a mortal Integer StateValue.
     * @param value the Integer to store.
     * @param duration the duration, in seconds, this should be maintained within
     * dCache state.
     */
    public IntegerStateValue(long value, long duration)
    {
        super(duration);
        _storage = value;
    }

    /**
     * Create an Ephemeral Integer StateValue.
     * @param value the Integer to store.
     */
    public IntegerStateValue(long value)
    {
        this(value, false);
    }


    /**
     * Create a Integer StateValue that is either immortal or ephemeral.
     * @param value the numerical value to store
     * @param isImmortal whether this metric is immortal. If false, then an ephemeral value is
     * created, equivalent to IntegerStateValue(value).
     */
    public IntegerStateValue(long value, boolean isImmortal)
    {
        super(isImmortal);
        _storage = value;
    }

    /**
     * Return a string representation.
     */
    @Override
    public String toString()
    {
        return Long.toString(_storage);
    }

    @Override
    public String getTypeName()
    {
        return "integer";
    }

    public long getValue()
    {
        return _storage;
    }

    /**
     *  Leaf-node specific support for the Visitor pattern.  See StateValue for inherited
     *  actual implementation and StateVisitor interface for more details.
     */
    @Override
    public void acceptVisitor(StatePath path, StateVisitor visitor)
    {
        visitor.visitInteger(path, this);
    }

    /**
     *  Override the default hashCode() method, to honour the hashCode() / equals() contract.
     */
    @Override
    public int hashCode()
    {
        return (int)_storage;
    }


    /**
     *  Override the default equals() method.
     */
    @Override
    public boolean equals(Object other)
    {
        if (!(other instanceof IntegerStateValue)) {
            return false;
        }

        IntegerStateValue otherValue = (IntegerStateValue) other;

        return _storage == otherValue._storage;
    }
}