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.interactive.pagenavigation;
18
19 import org.apache.pdfbox.cos.COSArray;
20 import org.apache.pdfbox.cos.COSBase;
21 import org.apache.pdfbox.cos.COSDictionary;
22 import org.apache.pdfbox.cos.COSName;
23
24 import org.apache.pdfbox.pdmodel.PDPage;
25 import org.apache.pdfbox.pdmodel.common.COSObjectable;
26 import org.apache.pdfbox.pdmodel.common.PDRectangle;
27
28 /**
29 * This a single bead in a thread in a PDF document.
30 *
31 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
32 * @version $Revision: 1.4 $
33 */
34 public class PDThreadBead implements COSObjectable
35 {
36
37
38 private COSDictionary bead;
39
40 /**
41 * Constructor that is used for a preexisting dictionary.
42 *
43 * @param b The underlying dictionary.
44 */
45 public PDThreadBead( COSDictionary b )
46 {
47 bead = b;
48 }
49
50 /**
51 * Default constructor.
52 *
53 */
54 public PDThreadBead()
55 {
56 bead = new COSDictionary();
57 bead.setName( "Type", "Bead" );
58 setNextBead( this );
59 setPreviousBead( this );
60 }
61
62 /**
63 * This will get the underlying dictionary that this object wraps.
64 *
65 * @return The underlying info dictionary.
66 */
67 public COSDictionary getDictionary()
68 {
69 return bead;
70 }
71
72 /**
73 * Convert this standard java object to a COS object.
74 *
75 * @return The cos object that matches this Java object.
76 */
77 public COSBase getCOSObject()
78 {
79 return bead;
80 }
81
82 /**
83 * This will get the thread that this bead is part of. This is only required
84 * for the first bead in a thread, so other beads 'may' return null.
85 *
86 * @return The thread that this bead is part of.
87 */
88 public PDThread getThread()
89 {
90 PDThread retval = null;
91 COSDictionary dic = (COSDictionary)bead.getDictionaryObject( "T" );
92 if( dic != null )
93 {
94 retval = new PDThread( dic );
95 }
96 return retval;
97 }
98
99 /**
100 * Set the thread that this bead is part of. This is only required for the
101 * first bead in a thread. Note: This property is set for you by the PDThread.setFirstBead() method.
102 *
103 * @param thread The thread that this bead is part of.
104 */
105 public void setThread( PDThread thread )
106 {
107 bead.setItem( "T", thread );
108 }
109
110 /**
111 * This will get the next bead. If this bead is the last bead in the list then this
112 * will return the first bead.
113 *
114 * @return The next bead in the list or the first bead if this is the last bead.
115 */
116 public PDThreadBead getNextBead()
117 {
118 return new PDThreadBead( (COSDictionary) bead.getDictionaryObject( "N" ) );
119 }
120
121 /**
122 * Set the next bead in the thread.
123 *
124 * @param next The next bead.
125 */
126 protected void setNextBead( PDThreadBead next )
127 {
128 bead.setItem( "N", next );
129 }
130
131 /**
132 * This will get the previous bead. If this bead is the first bead in the list then this
133 * will return the last bead.
134 *
135 * @return The previous bead in the list or the last bead if this is the first bead.
136 */
137 public PDThreadBead getPreviousBead()
138 {
139 return new PDThreadBead( (COSDictionary) bead.getDictionaryObject( "V" ) );
140 }
141
142 /**
143 * Set the previous bead in the thread.
144 *
145 * @param previous The previous bead.
146 */
147 protected void setPreviousBead( PDThreadBead previous )
148 {
149 bead.setItem( "V", previous );
150 }
151
152 /**
153 * Append a bead after this bead. This will correctly set the next/previous beads in the
154 * linked list.
155 *
156 * @param append The bead to insert.
157 */
158 public void appendBead( PDThreadBead append )
159 {
160 PDThreadBead nextBead = getNextBead();
161 nextBead.setPreviousBead( append );
162 append.setNextBead( nextBead );
163 setNextBead( append );
164 append.setPreviousBead( this );
165 }
166
167 /**
168 * Get the page that this bead is part of.
169 *
170 * @return The page that this bead is part of.
171 */
172 public PDPage getPage()
173 {
174 PDPage page = null;
175 COSDictionary dic = (COSDictionary)bead.getDictionaryObject( "P" );
176 if( dic != null )
177 {
178 page = new PDPage( dic );
179 }
180 return page;
181 }
182
183 /**
184 * Set the page that this bead is part of. This is a required property and must be
185 * set when creating a new bead. The PDPage object also has a list of beads in the natural
186 * reading order. It is recommended that you add this object to that list as well.
187 *
188 * @param page The page that this bead is on.
189 */
190 public void setPage( PDPage page )
191 {
192 bead.setItem( "P", page );
193 }
194
195 /**
196 * The rectangle on the page that this bead is part of.
197 *
198 * @return The part of the page that this bead covers.
199 */
200 public PDRectangle getRectangle()
201 {
202 PDRectangle rect = null;
203 COSArray array = (COSArray)bead.getDictionaryObject( COSName.R );
204 if( array != null )
205 {
206 rect = new PDRectangle( array );
207 }
208 return rect;
209 }
210
211 /**
212 * Set the rectangle on the page that this bead covers.
213 *
214 * @param rect The portion of the page that this bead covers.
215 */
216 public void setRectangle( PDRectangle rect )
217 {
218 bead.setItem( COSName.R, rect );
219 }
220 }