1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure;
18
19 import org.apache.pdfbox.cos.COSDictionary;
20 import org.apache.pdfbox.cos.COSName;
21 import org.apache.pdfbox.pdmodel.common.PDDictionaryWrapper;
22
23 /**
24 * An attribute object.
25 *
26 * @author <a href="mailto:Johannes%20Koch%20%3Ckoch@apache.org%3E">Johannes Koch</a>
27 * @version $Revision: $
28 *
29 */
30 public abstract class PDAttributeObject extends PDDictionaryWrapper
31 {
32
33 /**
34 * Creates an attribute object.
35 *
36 * @param dictionary the dictionary
37 * @return the attribute object
38 */
39 public static PDAttributeObject create(COSDictionary dictionary)
40 {
41 String owner = dictionary.getNameAsString(COSName.O);
42 if (PDUserAttributeObject.USER_PROPERTIES.equals(owner))
43 {
44 return new PDUserAttributeObject(dictionary);
45 }
46 return new PDDefaultAttributeObject(dictionary);
47 }
48
49 private PDStructureElement structureElement;
50
51 /**
52 * Gets the structure element.
53 *
54 * @return the structure element
55 */
56 private PDStructureElement getStructureElement()
57 {
58 return this.structureElement;
59 }
60
61 /**
62 * Sets the structure element.
63 *
64 * @param structureElement the structure element
65 */
66 protected void setStructureElement(PDStructureElement structureElement)
67 {
68 this.structureElement = structureElement;
69 }
70
71
72 /**
73 * Default constructor.
74 */
75 public PDAttributeObject()
76 {
77 }
78
79 /**
80 * Creates a new attribute object with a given dictionary.
81 *
82 * @param dictionary the dictionary
83 */
84 public PDAttributeObject(COSDictionary dictionary)
85 {
86 super(dictionary);
87 }
88
89
90 /**
91 * Returns the owner of the attributes.
92 *
93 * @return the owner of the attributes
94 */
95 public String getOwner()
96 {
97 return this.getCOSDictionary().getNameAsString(COSName.O);
98 }
99
100 /**
101 * Sets the owner of the attributes.
102 *
103 * @param owner the owner of the attributes
104 */
105 protected void setOwner(String owner)
106 {
107 this.getCOSDictionary().setName(COSName.O, owner);
108 }
109
110 /**
111 * Detects whether there are no properties in the attribute object.
112 *
113 * @return <code>true</code> if the attribute object is empty,
114 * <code>false</code> otherwise
115 */
116 public boolean isEmpty()
117 {
118 // only entry is the owner?
119 return (this.getCOSDictionary().size() == 1) && (this.getOwner() != null);
120 }
121
122
123 /**
124 * Notifies the attribute object change listeners if the attribute is changed.
125 *
126 * @param oldValue old value
127 * @param newValue new value
128 */
129 protected void potentiallyNotifyChanged(Object oldValue, Object newValue)
130 {
131 if (this.isValueChanged(oldValue, newValue))
132 {
133 this.notifyChanged();
134 }
135 }
136
137 /**
138 * Is the value changed?
139 *
140 * @param oldValue old value
141 * @param newValue new value
142 * @return <code>true</code> if the value is changed, <code>false</code>
143 * otherwise
144 */
145 private boolean isValueChanged(Object oldValue, Object newValue)
146 {
147 if (oldValue == null)
148 {
149 if (newValue == null)
150 {
151 return false;
152 }
153 return true;
154 }
155 return !oldValue.equals(newValue);
156 }
157
158 /**
159 * Notifies the attribute object change listeners about a change in this
160 * attribute object.
161 */
162 protected void notifyChanged()
163 {
164 if (this.getStructureElement() != null)
165 {
166 this.getStructureElement().attributeChanged(this);
167 }
168 }
169
170 @Override
171 public String toString()
172 {
173 return new StringBuilder("O=").append(this.getOwner()).toString();
174 }
175
176 protected static String arrayToString(Object[] array)
177 {
178 StringBuilder sb = new StringBuilder("[");
179 for (int i = 0; i < array.length; i++)
180 {
181 if (i > 0)
182 {
183 sb.append(", ");
184 }
185 sb.append(array[i]);
186 }
187 return sb.append(']').toString();
188 }
189
190 protected static String arrayToString(float[] array)
191 {
192 StringBuilder sb = new StringBuilder("[");
193 for (int i = 0; i < array.length; i++)
194 {
195 if (i > 0)
196 {
197 sb.append(", ");
198 }
199 sb.append(array[i]);
200 }
201 return sb.append(']').toString();
202 }
203
204 }