CountAggregate.java

/*******************************************************************************
 * Copyright (c) 2006 IBM Corporation.
 * 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
 *
 * Contributors:
 *     IBM Corporation - Jeff Briggs, Henry Hughes, Ryan Morse
 *******************************************************************************/

package org.eclipse.linuxtools.systemtap.graphing.core.aggregates;

public class CountAggregate implements IDataAggregate {

    /**
     * Ensure column isn't empty, then get the count of the column's values.
     *
     * @param column The column to count.
     *
     * @return Count of that column's values.
     */
    @Override
    public Number aggregate(Number[] column) {
        if(column == null || column.length == 0) {
            return null;
        }

        int num = 0;

        for(int i=0; i<column.length; i++) {
            num++;
        }

        return Integer.valueOf(num);
    }

    @Override
    public String getID() {
        return ID;
    }

    public static final String ID = "org.eclipse.linuxtools.systemtap.graphing.core.aggregates.CountAggregate"; //$NON-NLS-1$
}