AggregationValue.java

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package org.opensolaris.os.dtrace;

/**
 * A value accumulated by an aggregating DTrace action such as {@code
 * count()} or {@code sum()}.  Each {@code AggregationValue} is
 * associated with a {@link Tuple} in an {@link AggregationRecord}.  In
 * other words it is a value in a key-value pair (each pair representing
 * an entry in a DTrace aggregation).
 * <p>
 * This value may be a single number or consist of multiple numbers,
 * such as a value distribution.  In the latter case, it still has a
 * single, composite value useful for display and/or comparison.
 *
 * @see AggregationRecord
 *
 * @author Tom Erickson
 */
public interface AggregationValue {
    /**
     * Gets the numeric value of this instance.
     *
     * @return non-null numeric value
     */
    public Number getValue();
}