KezvhLib/src-lib/net/kezvh/collections/MapValuesEquivalence.java

   1 package net.kezvh.collections;
   2
   3 import java.util.Map;
   4 import java.util.Map.Entry;
   5
   6 import net.kezvh.functional.lambda.EquivalenceRelation;
   7
   8 /**
   9  * @author afflux
  10  * @param <K> FIXME comment
  11  * @param <V> FIXME comment
  12  */
  13 public final class MapValuesEquivalence<K, V> implements EquivalenceRelation<Map<K, V>> {
  14         /**
  15          *
  16          */
  17         public static final MapValuesEquivalence<?, ?> VALUES_EQUAL_EQUIVALATOR = new MapValuesEquivalence<Object, Object>();
  18
  19         private final EquivalenceRelation<V> valuesEquivalator;
  20
  21         /**
  22          *
  23          */
  24         @SuppressWarnings("unchecked")
  25         public MapValuesEquivalence() {
  26                 this((EquivalenceRelation<V>) EquivalenceRelation.EQUALS);
  27         }
  28
  29         /**
  30          * @param valuesEquivalator FIXME comment
  31          */
  32         public MapValuesEquivalence(final EquivalenceRelation<V> valuesEquivalator) {
  33                 this.valuesEquivalator = valuesEquivalator;
  34         }
  35
  36         /**
  37          * @param param1 FIXME comment
  38          * @param param2 FIXME comment
  39          * @return x
  40          */
  41         public Boolean op(final Map<K, V> param1, final Map<K, V> param2) {
  42                 if (param1 == null)
  43                         return param2 == null;
  44                 if (param2 == null)
  45                         return false;
  46
  47                 if (!param1.keySet().equals(param2.keySet()))
  48                         return false;
  49
  50                 return this.valuesEqual(param1, param2);
  51         }
  52
  53         private boolean valuesEqual(final Map<K, V> m1, final Map<K, V> m2) {
  54                 for (final Entry<K, V> entry : m1.entrySet()) {
  55                         final K key = entry.getKey();
  56                         final V value1 = entry.getValue();
  57                         final V value2 = m2.get(key);
  58
  59                         if (!this.valuesEquivalator.op(value1, value2))
  60                                 return false;
  61                 }
  62
  63                 return true;
  64         }
  65 }