Dual Key Hash Map : Hash Code « Development Class « Java






Dual Key Hash Map

      
/*
 * @(#)DualKeyHashMap.java  1.0 May 5, 2008
 *
 *  The MIT License
 *
 *  Copyright (c) 2008 Malachi de AElfweald <malachid@gmail.com>
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a copy
 *  of this software and associated documentation files (the "Software"), to deal
 *  in the Software without restriction, including without limitation the rights
 *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *  copies of the Software, and to permit persons to whom the Software is
 *  furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be included in
 *  all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 *  THE SOFTWARE.
 */
//package org.eoti.util;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class DualKeyHashMap<XKEY, YKEY, VALUE> extends
    HashMap<DualKeyMap.DualKey<XKEY, YKEY>, VALUE> implements
    DualKeyMap<XKEY, YKEY, VALUE> {
  static class SimpleDualKey<XKEY, YKEY> implements DualKey<XKEY, YKEY> {
    protected XKEY xKey;
    protected YKEY yKey;

    public SimpleDualKey(XKEY xKey, YKEY yKey) {
      this.xKey = xKey;
      this.yKey = yKey;
    }

    public XKEY getXKey() {
      return xKey;
    }

    public YKEY getYKey() {
      return yKey;
    }

    public int hashCode() {
      return toString().hashCode();
    }

    public boolean equals(Object obj) {
      return hashCode() == obj.hashCode();
    }

    public String toString() {
      return String.format("[%s [xkey=%s][ykey=%s]", this.getClass()
          .getName(), xKey.toString(), yKey.toString());
    }
  }

  public DualKeyHashMap(int initialCapacity, float loadFactor) {
    super(initialCapacity, loadFactor);
  }

  public DualKeyHashMap(int initialCapacity) {
    super(initialCapacity);
  }

  public DualKeyHashMap() {
    super();
  }

  public DualKeyHashMap(Map<? extends DualKey<XKEY, YKEY>, ? extends VALUE> m) {
    super(m);
  }

  public boolean containsXKey(XKEY xKey) {
    for (DualKey<XKEY, YKEY> key : keySet()) {
      if (key.getXKey().equals(xKey))
        return true;
    }
    return false;
  }

  public boolean containsYKey(YKEY yKey) {
    for (DualKey<XKEY, YKEY> key : keySet()) {
      if (key.getYKey().equals(yKey))
        return true;
    }
    return false;
  }

  public VALUE get(XKEY xKey, YKEY yKey) {
    return super.get(new SimpleDualKey<XKEY, YKEY>(xKey, yKey));
  }

  public Set<XKEY> getXKeySet() {
    HashSet<XKEY> xKeys = new HashSet<XKEY>();
    for (DualKey<XKEY, YKEY> key : keySet())
      xKeys.add(key.getXKey());

    return xKeys;
  }

  public Set<YKEY> getYKeySet() {
    HashSet<YKEY> yKeys = new HashSet<YKEY>();
    for (DualKey<XKEY, YKEY> key : keySet())
      yKeys.add(key.getYKey());

    return yKeys;
  }

  public VALUE put(XKEY xKey, YKEY yKey, VALUE value) {
    return put(new SimpleDualKey<XKEY, YKEY>(xKey, yKey), value);
  }

  public void putAll(DualKeyMap<XKEY, YKEY, VALUE> map) {
    super.putAll(map);
  }

  public VALUE remove(XKEY xKey, YKEY yKey) {
    return remove(new SimpleDualKey<XKEY, YKEY>(xKey, yKey));
  }

}

interface DualKeyMap<XKEY, YKEY, VALUE> extends
    Map<DualKeyMap.DualKey<XKEY, YKEY>, VALUE> {
  static interface DualKey<XKEY, YKEY> {
    public XKEY getXKey();

    public YKEY getYKey();

    public int hashCode();

    public boolean equals(Object obj);
  }

  // static interface Entry<XKEY,YKEY,VALUE> extends Map.Entry<Key<XKEY,YKEY>,
  // VALUE>
  // public void clear();
  public boolean containsXKey(XKEY xKey);

  public boolean containsYKey(YKEY yKey);

  // public Set<Entry<XKEY,YKEY,VALUE>> entrySet();
  // public boolean equals(Object obj);
  public VALUE get(XKEY xKey, YKEY yKey);

  // public int hashCode();
  // public boolean isEmpty();
  public Set<XKEY> getXKeySet();

  public Set<YKEY> getYKeySet();

  public VALUE put(XKEY xKey, YKEY yKey, VALUE value);

  public void putAll(DualKeyMap<XKEY, YKEY, VALUE> map);

  public VALUE remove(XKEY xKey, YKEY yKey);
  // public int size();
  // public Collection<VALUE> values();
}

   
    
    
    
    
    
  








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