FeatureUtil.java

package com.vividsolutions.jump.feature;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

import com.vividsolutions.jts.geom.Geometry;

public class FeatureUtil {
	
	/**
	 * Creates a new Feature from the given Geometry, with nominal values for
	 * the attributes.
	 * @param g the Geometry to convert
	 * @param schema metadata for the Feature to create
	 * @return a new Feature containing the Geometry and default values for the
	 * attributes
	 */
//	public static Feature toFeature(Geometry g, FeatureSchema schema) {
//	    Feature feature = new BasicFeature(schema);
//	    feature.setGeometry(g);
//	    return feature;
//	}

	public static List toGeometries(Collection features) {
	    ArrayList list = new ArrayList();
	
	    for (Iterator i = features.iterator(); i.hasNext();) {
	        Feature feature = (Feature) i.next();
	        list.add(feature.getGeometry());
	    }
	
	    return list;
	}
	
	public static class IDComparator implements Comparator {
		/**
		 *  Compares two Features for order based on their ID.
		 *
		 *@param  o1  the first <code>Feature</code>
		 *@param  o2  the second <code>Feature</code>
		 *
		 *@return    a negative integer, zero, or a positive integer
		 *        as the first argument is less than, equal to,
		 *        or greater than the second.
		 */
		public int compare(Object o1, Object o2) {
			Feature f1 = (Feature) o1;
			Feature f2 = (Feature) o2;

			if (f1.getID() < f2.getID()) {
				return -1;
			}

			if (f1.getID() > f2.getID()) {
				return 1;
			}

			return 0;
		}
	}	
	
	private static int lastID = 0;
	
	public static int nextID() { return ++lastID; }

    /**
     * Although Feature implements Cloneable, this method is useful
     * when the two Features are implemented with different classes.
     */
    public static void copyAttributes(Feature a, Feature b) {
        for (int i = 0; i < a.getSchema().getAttributeCount(); i++) {
            b.setAttribute(i, a.getAttribute(i));
        }
    }

    public static boolean areAllNonSpatialAttributesNull(Feature feature) {
        for (int i = 0; i < feature.getSchema().getAttributeCount(); i++) {
            if (AttributeType.GEOMETRY == feature.getSchema().getAttributeType(i)) {
                continue;
            }
            if (feature.getAttribute(i) != null) {
                return false;
            }
        }
        return true;
    }	
	
}