1 package edu.berkeley.sbp.util;
4 import java.lang.reflect.*;
5 import java.lang.ref.*;
6 import edu.berkeley.sbp.util.*;
7 import edu.berkeley.sbp.*;
9 /** implementation of <tt>Topology</tt> for any class via equals()/hashCode() */
10 public class DiscreteTopology<V> implements Topology<V> {
12 HashSet<V> hs = new HashSet<V>();
14 public DiscreteTopology() { }
15 public DiscreteTopology(V v) { hs.add(v); }
16 DiscreteTopology(HashSet<V> hs) { this.hs.addAll(hs); }
18 public Topology<V> fresh() { return new DiscreteTopology<V>(); }
19 public Topology<V> dup() { return new DiscreteTopology<V>(this.hs); }
21 public HashSet<V> hs() {
22 HashSet<V> ret = new HashSet<V>();
27 public void add(Topology<V> t) { hs.addAll(((DiscreteTopology<V>)t).hs); }
28 public void remove(Topology<V> t) { hs.removeAll(((DiscreteTopology<V>)t).hs); }
29 public void add(V v) { hs.add(v); }
30 public void remove(V v) { hs.remove(v); }
31 public boolean contains(V v) { return hs.contains(v); }
33 public Topology<V> complement() { /*return dup(hs.complement());*/ throw new Error(); }
34 public Topology<V> intersect(Topology<V> t) { return new DiscreteTopology(hs().retainAll(((DiscreteTopology<V>)t).hs)); }
35 public Topology<V> minus(Topology<V> t) { return new DiscreteTopology(hs().removeAll(((DiscreteTopology<V>)t).hs)); }
36 public Topology<V> union(Topology<V> t) { return new DiscreteTopology(hs().addAll(((DiscreteTopology<V>)t).hs)); }
37 public boolean disjoint(Topology<V> t) { return ((DiscreteTopology)intersect(t)).size()==0; }
38 public boolean containsAll(Topology<V> t) { return hs.containsAll(((DiscreteTopology<V>)t).hs); }
40 public int hashCode() { return hs.hashCode(); }
41 public boolean equals(Object o) { return o!=null && o instanceof DiscreteTopology && ((DiscreteTopology<V>)o).hs.equals(hs); }
42 public int size() { return hs.size(); }