package edu.northwestern.at.utils; /* Please see the license information at the end of this file. */ import java.util.*; /** Two dimensional HashMap. * * <p> * The two dimensional hash map is implemented as a hash map of * hash maps. Each "row" key points to a "column" hash map. * </p> * * <p> * Example of use: * </p> * * <blockquote> * <p> * <code> * Map2D map = new HashMap2D(); * map.put( "a" , "b" , "my value" ); * String s = map.get( "a" , "b" ); * </code> * </p> * </blockquote> * * <p> * Note: HashMap2D does not implement the Map interface. * </p> */ public class HashMap2D<K1 extends Comparable, K2 extends Comparable, V> implements Map2D<K1, K2, V> { /** Local map. */ protected Map<K1 , Map<K2,V>> localMap; /** Initial capacity for child hash maps. */ protected int capacity = 100; /** Create two dimensional hash map. */ public HashMap2D() { localMap = MapFactory.createNewMap( capacity ); } /** Create two dimensional hash map with specified initial row capacity. * * @param initialCapacity */ public HashMap2D( int initialCapacity ) { localMap = MapFactory.createNewMap( initialCapacity ); this.capacity = initialCapacity; } /** Clear all entries from this map and its child maps. */ public void clear() { Iterator<K1> iterator = localMap.keySet().iterator(); while ( iterator.hasNext() ) { Map<K2,V> columnMap = localMap.get( iterator.next() ); if ( columnMap != null ) { columnMap.clear(); } } localMap.clear(); } /** Return number of entries. * * @return Number of entries in map. * * <p> * The number of entries is given by the sum of the number of * entries for each submap. * </p> */ public int size() { int result = 0; Iterator<K1> iterator = localMap.keySet().iterator(); while ( iterator.hasNext() ) { Map<K2,V> columnMap = localMap.get( iterator.next() ); if ( columnMap != null ) { result += columnMap.size(); } } return result; } /** Determine if map contains a key pair. * * @param rowKey Row key. * @param columnKey Column key. * * @return true if entry exists, false otherwise. */ public boolean containsKeys ( Object rowKey , Object columnKey ) { boolean result = false; Map<K2,V> map = localMap.get( rowKey ); if ( map != null ) { result = map.containsKey( columnKey ) ; } return result; } /** Determine if map contains a compound key. * * @param key Compound key. * * @return true if entry exists, false otherwise. */ public boolean containsKey ( CompoundKey key ) { boolean result = false; if ( key != null ) { Comparable[] keyValues = key.getKeyValues(); Map<K2,V> map = localMap.get( keyValues[ 0 ] ); if ( map != null ) { result = map.containsKey( keyValues[ 1 ] ); } } return result; } /** Get value at specified (rowKey, columnKey) position. * * @param rowKey Row key. * @param columnKey Column key. * * @return The value at the specified (rowKey, columnKey) position. */ public V get( Object rowKey , Object columnKey ) { V result = null; Map<K2,V> map = localMap.get( rowKey ); if ( map != null ) { result = map.get( columnKey ); } return result; } /** Get value at specified CompoundKey position. * * @param key Compound key. * * @return The value at the specified compound key position. */ public V get( CompoundKey key ) { V result = null; if ( key != null ) { Comparable[] keyValues = key.getKeyValues(); Map<K2,V> map = localMap.get( keyValues[ 0 ] ); if ( map != null ) { result = map.get( keyValues[ 1 ] ); } } return result; } /** Add value for specified (rowKey, columnKey) . * * @param rowKey Row key. * @param columnKey Column key. * @param value Value to store. * * @return Previous value for (rowKey, columnKey). * May be null. */ public V put ( K1 rowKey , K2 columnKey , V value ) { V previousValue = null; Map<K2,V> map = localMap.get( rowKey ); if ( map != null ) { previousValue = map.get( columnKey ); } else { map = MapFactory.createNewMap(); } map.put( columnKey , value ); // Add or update value in column map // for specified column key. localMap.put( rowKey , map ); // Return previous value. return previousValue; } /** Remove entry at (rowKey, columnKey). * * @param rowKey Row key. * @param columnKey Column key. * * @return Previous value for (rowKey, columnKey). * May be null. */ public V remove( Object rowKey , Object columnKey ) { V result = null; Map<K2,V> map = localMap.get( rowKey ); if ( map != null ) { result = map.get( columnKey ); if ( result != null ) { map.remove( columnKey ); } } return result; } /** Get the compound key set. * * @return The compound key set. */ public Set<CompoundKey> keySet() { Set<CompoundKey> result = SetFactory.createNewSet(); for ( K1 rowKey : localMap.keySet() ) { Map<K2,V> colMap = localMap.get( rowKey ); if ( colMap != null ) { for ( K2 columnKey : colMap.keySet() ) { CompoundKey key = new CompoundKey ( (Comparable)rowKey , (Comparable)columnKey ); result.add( key ); } } } return result; } /** Get row key set. * * @return rows key set. */ public Set<K1> rowKeySet() { return localMap.keySet(); } /** Get column key set. * * @return column key set. */ public Set<K2> columnKeySet() { Set<K2> result = SetFactory.createNewSet(); for ( K1 rowKey : localMap.keySet() ) { Map<K2,V> colMap = localMap.get( rowKey ); if ( colMap != null ) { result.addAll( colMap.keySet() ); } } return result; } public Set<K2> columnKeySet( Object rowKey ) { Set<K2> result = SetFactory.createNewSet(); Map<K2,V> colMap = localMap.get( rowKey ); if ( colMap != null ) { result = colMap.keySet(); } return result; } /** Return formatted string displaying all entries. * * @return Formatted string displaying all entries. */ public String toString() { StringBuffer sb = new StringBuffer(); Iterator<CompoundKey> iterator = keySet().iterator(); while ( iterator.hasNext() ) { CompoundKey key = iterator.next(); if ( sb.length() > 0 ) { sb.append( "; " ); } sb.append( key.toString() ); sb.append( "=" ); sb.append( get( key ) ); } return "[" + sb.toString() + "]"; } } /* Copyright (c) 2008, 2009 by Northwestern University. All rights reserved. Developed by: Academic and Research Technologies Northwestern University http://www.it.northwestern.edu/about/departments/at/ Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal with 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: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimers. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimers in the documentation and/or other materials provided with the distribution. * Neither the names of Academic and Research Technologies, Northwestern University, nor the names of its contributors may be used to endorse or promote products derived from this Software without specific prior written permission. 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 CONTRIBUTORS 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 WITH THE SOFTWARE. */