1 /*
2 $Id: SpreadMap.java,v 1.2 2005/07/23 12:09:47 phk Exp $
3
4 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
5
6 Redistribution and use of this software and associated documentation
7 ("Software"), with or without modification, are permitted provided
8 that the following conditions are met:
9
10 1. Redistributions of source code must retain copyright
11 statements and notices. Redistributions must also contain a
12 copy of this document.
13
14 2. Redistributions in binary form must reproduce the
15 above copyright notice, this list of conditions and the
16 following disclaimer in the documentation and/or other
17 materials provided with the distribution.
18
19 3. The name "groovy" must not be used to endorse or promote
20 products derived from this Software without prior written
21 permission of The Codehaus. For written permission,
22 please contact info@codehaus.org.
23
24 4. Products derived from this Software may not be called "groovy"
25 nor may "groovy" appear in their names without prior written
26 permission of The Codehaus. "groovy" is a registered
27 trademark of The Codehaus.
28
29 5. Due credit should be given to The Codehaus -
30 http://groovy.codehaus.org/
31
32 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
33 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
34 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
36 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43 OF THE POSSIBILITY OF SUCH DAMAGE.
44
45 */
46 package groovy.lang;
47
48 import java.util.HashMap;
49 import java.util.Map;
50 import java.util.Iterator;
51
52 import org.codehaus.groovy.runtime.InvokerHelper;
53
54 /***
55 * Represents a spreadable map which extends java.util.HashMap.
56 *
57 * @author Pilho Kim
58 * @version $Revision: 1.2 $
59 */
60 public class SpreadMap extends HashMap {
61
62 private Map mapData;
63 private int hashCode;
64
65 public SpreadMap(Object[] values) {
66 mapData = new HashMap(values.length / 2);
67 int i = 0;
68 while (i < values.length) {
69 mapData.put(values[i++], values[i++]);
70 }
71 }
72
73 public SpreadMap(Map map) {
74 this.mapData = map;
75 }
76
77 public Object get(Object obj) {
78 return mapData.get(obj);
79 }
80
81 public Object put(Object key, Object value) {
82 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so ("
83 + key + ": " + value + ") cannot be added.");
84 }
85
86 public Object remove(Object key) {
87 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so the key ("
88 + key + ") cannot be deleteded.");
89 }
90
91 public void putAll(Map t) {
92 throw new RuntimeException("SpreadMap: " + this + " is an immutable map, and so the map ("
93 + t + ") cannot be put in this spreadMap.");
94 }
95
96 public int size() {
97 return mapData.keySet().size();
98 }
99
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 (this == null && that == null)
109 return true;
110 else if (this != null && that == null)
111 return false;
112 else if (this == null && that != null)
113 return false;
114
115 if (size() == that.size()) {
116 SpreadMap other = (SpreadMap) that;
117 Iterator iter = mapData.keySet().iterator();
118 for (; iter.hasNext(); ) {
119 Object key = iter.next();
120 if (! InvokerHelper.compareEqual(get(key), other.get(key)) ) {
121 return false;
122 }
123 }
124 return true;
125 }
126 return false;
127 }
128
129
130 public int hashCode() {
131 if (hashCode == 0) {
132 Iterator iter = mapData.keySet().iterator();
133 for (; iter.hasNext(); ) {
134 Object key = iter.next();
135 int hash = (key != null) ? key.hashCode() : 0xbabe;
136 hashCode ^= hash;
137 }
138 }
139 return hashCode;
140 }
141
142 /***
143 * Returns the string expression of <code>this</code>.
144 *
145 * @return the string expression of <code>this</code>
146 */
147 public String toString() {
148 if (mapData.isEmpty()) {
149 return "*:[:]";
150 }
151 StringBuffer buff = new StringBuffer("*:[");
152 Iterator iter = mapData.keySet().iterator();
153 for (; iter.hasNext(); ) {
154 Object key = iter.next();
155 buff.append(key + ":" + mapData.get(key));
156 if (iter.hasNext())
157 buff.append(", ");
158 }
159 buff.append("]");
160 return buff.toString();
161 }
162 }