001 /*
002 $Id: SpreadMap.java 4098 2006-10-10 16:09:48Z blackdrag $
003
004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005
006 Redistribution and use of this software and associated documentation
007 ("Software"), with or without modification, are permitted provided
008 that the following conditions are met:
009
010 1. Redistributions of source code must retain copyright
011 statements and notices. Redistributions must also contain a
012 copy of this document.
013
014 2. Redistributions in binary form must reproduce the
015 above copyright notice, this list of conditions and the
016 following disclaimer in the documentation and/or other
017 materials provided with the distribution.
018
019 3. The name "groovy" must not be used to endorse or promote
020 products derived from this Software without prior written
021 permission of The Codehaus. For written permission,
022 please contact info@codehaus.org.
023
024 4. Products derived from this Software may not be called "groovy"
025 nor may "groovy" appear in their names without prior written
026 permission of The Codehaus. "groovy" is a registered
027 trademark of The Codehaus.
028
029 5. Due credit should be given to The Codehaus -
030 http://groovy.codehaus.org/
031
032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043 OF THE POSSIBILITY OF SUCH DAMAGE.
044
045 */
046 package groovy.lang;
047
048 import java.util.HashMap;
049 import java.util.Map;
050 import java.util.Iterator;
051
052 import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;
053
054 /**
055 * Represents a spreadable map which extends java.util.HashMap.
056 *
057 * @author Pilho Kim
058 * @version $Revision: 4098 $
059 */
060 public class SpreadMap extends HashMap {
061
062 private Map mapData;
063 private int hashCode;
064
065 public SpreadMap(Object[] values) {
066 mapData = new HashMap(values.length / 2);
067 int i = 0;
068 while (i < values.length) {
069 mapData.put(values[i++], values[i++]);
070 }
071 }
072
073 public SpreadMap(Map map) {
074 this.mapData = map;
075 }
076
077 public Object get(Object obj) {
078 return mapData.get(obj);
079 }
080
081 public Object put(Object key, Object value) {
082 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so ("
083 + key + ": " + value + ") cannot be added.");
084 }
085
086 public Object remove(Object key) {
087 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so the key ("
088 + key + ") cannot be deleteded.");
089 }
090
091 public void putAll(Map t) {
092 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so the map ("
093 + t + ") cannot be put in this spreadMap.");
094 }
095
096 public int size() {
097 return mapData.keySet().size();
098 }
099
100 public boolean equals(Object that) {
101 if (that instanceof SpreadMap) {
102 return equals((SpreadMap) that);
103 }
104 return false;
105 }
106
107 public boolean equals(SpreadMap that) {
108 if (that == null) return false;
109
110 if (size() == that.size()) {
111 SpreadMap other = (SpreadMap) that;
112 Iterator iter = mapData.keySet().iterator();
113 for (; iter.hasNext(); ) {
114 Object key = iter.next();
115 if (! DefaultTypeTransformation.compareEqual(get(key), other.get(key)) ) {
116 return false;
117 }
118 }
119 return true;
120 }
121 return false;
122 }
123
124
125 public int hashCode() {
126 if (hashCode == 0) {
127 Iterator iter = mapData.keySet().iterator();
128 for (; iter.hasNext(); ) {
129 Object key = iter.next();
130 int hash = (key != null) ? key.hashCode() : 0xbabe;
131 hashCode ^= hash;
132 }
133 }
134 return hashCode;
135 }
136
137 /**
138 * Returns the string expression of <code>this</code>.
139 *
140 * @return the string expression of <code>this</code>
141 */
142 public String toString() {
143 if (mapData.isEmpty()) {
144 return "*:[:]";
145 }
146 StringBuffer buff = new StringBuffer("*:[");
147 Iterator iter = mapData.keySet().iterator();
148 for (; iter.hasNext(); ) {
149 Object key = iter.next();
150 buff.append(key + ":" + mapData.get(key));
151 if (iter.hasNext())
152 buff.append(", ");
153 }
154 buff.append("]");
155 return buff.toString();
156 }
157 }