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/*
* The JTS Topology Suite is a collection of Java classes that
* implement the fundamental operations required to validate a given
* geo-spatial data set to a known topological specification.
*
* Copyright (C) 2001 Vivid Solutions
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* For more information, contact:
*
* Vivid Solutions
* Suite #1A
* 2328 Government Street
* Victoria BC V8T 5G5
* Canada
*
* (250)385-6040
* www.vividsolutions.com
*/
package com.vividsolutions.jts.index.strtree;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
/**
* One-dimensional version of an STR-packed R-tree. SIR stands for
* "Sort-Interval-Recursive". STR-packed R-trees are described in:
* P. Rigaux, Michel Scholl and Agnes Voisard. Spatial Databases With
* Application To GIS. Morgan Kaufmann, San Francisco, 2002.
*
* This class is thread-safe. Building the tree is synchronized,
* and querying is stateless.
*
* @see STRtree
*
* @version 1.7
*/
public class SIRtree extends AbstractSTRtree {
private Comparator comparator = new Comparator() {
public int compare(Object o1, Object o2) {
return compareDoubles(
((Interval)((Boundable)o1).getBounds()).getCentre(),
((Interval)((Boundable)o2).getBounds()).getCentre());
}
};
private IntersectsOp intersectsOp = new IntersectsOp() {
public boolean intersects(Object aBounds, Object bBounds) {
return ((Interval)aBounds).intersects((Interval)bBounds);
}
};
/**
* Constructs an SIRtree with the default node capacity.
*/
public SIRtree() { this(10); }
/**
* Constructs an SIRtree with the given maximum number of child nodes that
* a node may have
*/
public SIRtree(int nodeCapacity) {
super(nodeCapacity);
}
protected AbstractNode createNode(int level) {
return new AbstractNode(level) {
protected Object computeBounds() {
Interval bounds = null;
for (Iterator i = getChildBoundables().iterator(); i.hasNext(); ) {
Boundable childBoundable = (Boundable) i.next();
if (bounds == null) {
bounds = new Interval((Interval)childBoundable.getBounds());
}
else {
bounds.expandToInclude((Interval)childBoundable.getBounds());
}
}
return bounds;
}
};
}
/**
* Inserts an item having the given bounds into the tree.
*/
public void insert(double x1, double x2, Object item) {
super.insert(new Interval(Math.min(x1, x2), Math.max(x1, x2)), item);
}
/**
* Returns items whose bounds intersect the given value.
*/
public List query(double x) {
return query(x, x);
}
/**
* Returns items whose bounds intersect the given bounds.
* @param x1 possibly equal to x2
*/
public List query(double x1, double x2) {
return super.query(new Interval(Math.min(x1, x2), Math.max(x1, x2)));
}
protected IntersectsOp getIntersectsOp() {
return intersectsOp;
}
protected Comparator getComparator() {
return comparator;
}
}