teichmann@5863: /* Copyright (C) 2011, 2012, 2013 by Bundesanstalt für Gewässerkunde
teichmann@5863:  * Software engineering by Intevation GmbH
teichmann@5863:  *
teichmann@5994:  * This file is Free Software under the GNU AGPL (>=v3)
teichmann@5863:  * and comes with ABSOLUTELY NO WARRANTY! Check out the
teichmann@5994:  * documentation coming with Dive4Elements River for details.
teichmann@5863:  */
teichmann@5863: 
teichmann@5831: package org.dive4elements.river.utils;
sascha@3013: 
gernotbelger@9415: import java.io.Serializable;
sascha@3013: import java.util.ArrayList;
sascha@3013: import java.util.Collections;
sascha@3026: import java.util.Iterator;
gernotbelger@9415: import java.util.List;
sascha@3013: 
felix@4318: /** km to value, searchable. Tolerance is at 10cm. */
gernotbelger@9415: public class KMIndex<A> implements Serializable, Iterable<KMIndex.Entry<A>> {
sascha@3013: 
gernotbelger@9415:     private static final long serialVersionUID = 1L;
sascha@3013: 
gernotbelger@9415:     private static final double EPSILON = 1e-4;
gernotbelger@9415: 
gernotbelger@9415:     public static class Entry<A> implements Serializable, Comparable<Entry<A>> {
gernotbelger@9415:         private static final long serialVersionUID = 1L;
gernotbelger@9415: 
gernotbelger@9415:         private final double km;
gernotbelger@9415: 
gernotbelger@9415:         private A value;
gernotbelger@9415: 
gernotbelger@9415:         public Entry(final double km) {
sascha@3013:             this.km = km;
sascha@3013:         }
sascha@3013: 
gernotbelger@9415:         public Entry(final double km, final A value) {
gernotbelger@9415:             this.km = km;
sascha@3013:             this.value = value;
sascha@3013:         }
sascha@3013: 
sascha@3013:         public double getKm() {
gernotbelger@9415:             return this.km;
sascha@3013:         }
sascha@3013: 
sascha@3013:         public A getValue() {
gernotbelger@9415:             return this.value;
sascha@3013:         }
sascha@3013: 
sascha@3013:         @Override
gernotbelger@9415:         public int compareTo(final Entry<A> other) {
gernotbelger@9415:             final double diff = this.km - other.km;
gernotbelger@9415:             if (diff < -EPSILON)
gernotbelger@9415:                 return -1;
gernotbelger@9415:             if (diff > +EPSILON)
gernotbelger@9415:                 return +1;
sascha@3013:             return 0;
sascha@3013:         }
sascha@3013: 
gernotbelger@9415:         public boolean epsilonEquals(final double otherKm) {
gernotbelger@9415:             return Math.abs(this.km - otherKm) < EPSILON;
sascha@3013:         }
gernotbelger@9415:     }
sascha@3013: 
gernotbelger@9415:     private List<Entry<A>> entries;
sascha@3013: 
sascha@3013:     public KMIndex() {
sascha@3013:         this(10);
sascha@3013:     }
sascha@3013: 
gernotbelger@9415:     public KMIndex(final int capacity) {
gernotbelger@9415:         this.entries = new ArrayList<>(capacity);
sascha@3013:     }
sascha@3013: 
gernotbelger@9415:     public void add(final double km, final A value) {
gernotbelger@9415:         this.entries.add(new Entry<>(km, value));
sascha@3013:     }
sascha@3013: 
sascha@3013:     public void sort() {
gernotbelger@9415:         Collections.sort(this.entries);
sascha@3013:     }
sascha@3013: 
andre@8613:     public int size() {
gernotbelger@9415:         return this.entries.size();
andre@8613:     }
andre@8613: 
gernotbelger@9415:     public Entry<A> get(final int idx) {
gernotbelger@9415:         return this.entries.get(idx);
andre@8613:     }
andre@8613: 
felix@7215:     /** Return the first entry at km. */
gernotbelger@9415:     public Entry<A> search(final double km) {
gernotbelger@9415:         for (final Entry<A> entry : this.entries) {
sascha@3013:             if (entry.epsilonEquals(km)) {
sascha@3013:                 return entry;
sascha@3013:             }
sascha@3013:         }
sascha@3013:         return null;
sascha@3013:     }
sascha@3013: 
gernotbelger@9415:     public Entry<A> binarySearch(final double km) {
gernotbelger@9415:         final int index = Collections.binarySearch(this.entries, new Entry<A>(km));
gernotbelger@9415:         return index >= 0 ? this.entries.get(index) : null;
sascha@3013:     }
sascha@3026: 
gernotbelger@9415:     @Override
sascha@3026:     public Iterator<Entry<A>> iterator() {
gernotbelger@9415:         return this.entries.iterator();
sascha@3026:     }
gernotbelger@9415: }