source: trunk/greenstone3-extensions/gs3build/src/org/greenstone/gsdl3/gs3build/util/HTMLBlock.java@ 12188

Last change on this file since 12188 was 12188, checked in by kjdon, 18 years ago

Initial revision
  • Property svn:keywords set to Author Date Id Revision
File size: 8.5 KB
Line 
1package org.greenstone.gsdl3.gs3build.util;
2
3import java.util.*;
4
5public class HTMLBlock
6{
7 Vector content;
8 int tagpos;
9 int endpos;
10
11 public HTMLBlock(int docpos)
12 {
13 this.content = new Vector(1);
14 this.tagpos = docpos;
15 }
16
17 public HTMLBlock(int docpos, int endpos)
18 {
19 this.content = new Vector(1);
20 this.tagpos = docpos;
21 this.endpos = endpos;
22 }
23
24 public void addTag(HTMLTag tag)
25 {
26 if (tag.endPos() > this.endpos){
27 this.endpos = tag.endPos();
28 }
29 content.addElement(tag);
30 }
31
32 /**
33 * @deprecccate
34 public void addText(String text)
35 { content.addElement(text);
36 }
37 */
38
39 public void addText(HTMLCText text)
40 {
41 if (text.endPos() > this.endpos){
42 this.endpos = text.endPos();
43 }
44 content.addElement(text);
45 }
46
47 /**
48 * @return HTML encoded <code>String</code> of the document
49 */
50 public String contentString()
51 {
52 int member;
53 StringBuffer reply;
54 String type;
55
56 reply = new StringBuffer();
57 for (member = 1; member < content.size() - 1; member ++){
58 /*if (content.elementAt(member) instanceof String){
59 reply.append((String) content.elementAt(member));
60 }
61 else
62 */
63 if (content.elementAt(member) instanceof HTMLCText){
64 reply.append(((HTMLCText) content.elementAt(member)).toString());
65 }
66 }
67 return reply.toString();
68 }
69
70 /**
71 * Returns document position of start of the block
72 */
73 public int startPos()
74 {
75 return this.tagpos;
76 }
77
78 /**
79 * Returns document position of end of the block
80 */
81 public int endPos()
82 {
83 return this.tagpos;
84 }
85
86 /**
87 * @return head (first) tag of the block
88 */
89 public HTMLTag headTag()
90 {
91 return ((HTMLTag) content.elementAt(0));
92 }
93
94 /**
95 * @return name (as a <code>String</code>) of the tag at the head of the block
96 */
97 public String headTagName()
98 {
99 return ((HTMLTag) content.elementAt(0)).tagName();
100 }
101
102 /**
103 * @return name of the tail (last) tag of the block as a <code>String</code>
104 */
105 public String tailTagName()
106 {
107 return (((HTMLTag) content.elementAt(content.size() - 1)).tagName());
108 }
109
110
111 /**
112 * @return: starting element character position of the item-th item
113 */
114 private int elementStartPos(int item)
115 {
116 Object element;
117 int pos = -1;
118
119 element = this.content.elementAt(item);
120 if (element instanceof HTMLTag){
121 pos = ((HTMLTag) element).startPos();
122 }
123 else if (element instanceof HTMLCText){
124 pos = ((HTMLCText) element).startPos();
125 }
126 return pos;
127 }
128
129 /**
130 * @return: ending element character position of the item-th item
131 */
132 private int elementEndPos(int item)
133 {
134 Object element;
135 int pos = -1;
136
137 element = this.content.elementAt(item);
138 if (element instanceof HTMLTag){
139 pos = ((HTMLTag) element).endPos();
140 }
141 else if (element instanceof HTMLCText){
142 pos = ((HTMLCText) element).endPos();
143 }
144 return pos;
145 }
146
147 /**
148 * @return the HTMLBlock of the indicated subitems
149 */
150 public HTMLBlock subBlock(int startitem, int enditem)
151 {
152 int i;
153 Object element;
154 HTMLBlock reply;
155 reply = new HTMLBlock(this.elementStartPos(startitem),
156 this.elementEndPos(enditem-1));
157 // copy all the bits
158 for (i = startitem; i < enditem; i++){
159 element = this.content.elementAt(i);
160 if (element instanceof HTMLTag){
161 reply.addTag((HTMLTag) element);
162 }
163 else if (element instanceof HTMLCText){
164 reply.addText((HTMLCText) element);
165 }
166 /*
167 else if (element instanceof String)
168 { reply.addText((String) element);
169 }
170 */
171 }
172 return reply;
173 }
174
175 /**
176 * Return the position of the given <code>HTMLBlock</code> within this block
177 * @return the tag index of the child block; or < 0 if not a chile
178 */
179 public int find(HTMLBlock subblock)
180 {
181 int start, end, at, attag;
182 HTMLTag tag;
183
184 start = 0;
185 end = this.content.size();
186 while (start != end){
187 /* compare positions */
188 at = (start + end) / 2;
189 attag = at;
190 while (attag < end &&
191 (content.elementAt(attag) instanceof HTMLTag) == false){
192 attag ++;
193 }
194
195 if (attag == end){
196 end = at;
197 continue;
198 }
199 tag = (HTMLTag) content.elementAt(attag);
200 if (tag.startPos() > subblock.startPos()){
201 end = at;
202 }
203 else if (tag.startPos() < subblock.startPos()){
204 start = attag + 1;
205 }
206 else {
207 return attag;
208 }
209 }
210 return -1;
211 }
212
213 /**
214 * @return The raw HTML of the block
215 */
216 public String HTMLString()
217 {
218 int loop;
219 StringBuffer reply;
220
221 reply = new StringBuffer();
222 for (loop = 0; loop < this.content.size(); loop ++){
223 /*
224 if (content.elementAt(loop) instanceof String)
225 { reply.append((String) content.elementAt(loop));
226 }
227 else
228 */
229 if (content.elementAt(loop) instanceof HTMLCText){
230 reply.append(((HTMLCText) content.elementAt(loop)).toString());
231 }
232 else if (content.elementAt(loop) instanceof HTMLTag){
233 reply.append(((HTMLTag) content.elementAt(loop)).toString());
234 }
235 }
236 return reply.toString();
237 }
238
239 /**
240 * @return The text of the block - no HTML tags. If no text is present, any
241 * <code>alt</code> information for <code>img</code> tags will be given
242 * instead
243 */
244 public String toString()
245 {
246 int member;
247 StringBuffer reply;
248 StringBuffer ireply;
249
250 reply = new StringBuffer("");
251 ireply = new StringBuffer("");
252 for (member = 0; member < content.size(); member ++){
253 /*if (content.elementAt(member) instanceof String)
254 { reply.append((String) content.elementAt(member));
255 }
256 */
257 if (content.elementAt(member) instanceof HTMLCText){
258 reply.append(((HTMLCText) content.elementAt(member)).toString());
259 }
260 else if (content.elementAt(member) instanceof HTMLTag){
261 if (((HTMLTag) content.elementAt(member)).tagName().equals("img")){
262 ireply.append(((HTMLTag) content.elementAt(member)).idValue("alt"));
263 }
264 }
265 }
266 reply = HTMLCText.cleanString(reply);
267 ireply = HTMLCText.cleanString(ireply);
268 // reply = reply.trim();
269 if (reply == null || reply.length() == 0){
270 return ireply.toString();
271 }
272 return reply.toString();
273 }
274
275 public HTMLObject elementAt(int at)
276 {
277 return (HTMLObject) this.content.elementAt(at);
278 }
279
280 /**
281 * @return the number of elements in the block
282 */
283 public int size()
284 {
285 return this.content.size();
286 }
287
288 /**
289 * @return an enumeration of all elements in the block
290 */
291 public Enumeration elements()
292 {
293 Enumeration enumer;
294
295 enumer = new HTMLBlockEnumerator(this);
296 return enumer;
297 }
298
299 /**
300 * @return an enumeration of all tags in the block
301 */
302 public Enumeration tagElements()
303 {
304 Enumeration enumer;
305
306 enumer = new HTMLBlockTagEnumerator(this);
307 return enumer;
308 }
309
310 /**
311 * Finalization method
312 */
313 protected void finalize() throws Throwable
314 {
315 this.content = null;
316 super.finalize();
317 }
318}
319
320final class HTMLBlockEnumerator implements Enumeration
321{
322 private HTMLBlock block;
323 int member;
324
325 public HTMLBlockEnumerator(HTMLBlock block)
326 {
327 this.block = block;
328 this.member = 0;
329 }
330
331 public Object nextElement()
332 {
333 Object element;
334
335 element = this.block.content.elementAt(member);
336 member ++;
337 return element;
338 }
339
340 public boolean hasMoreElements()
341 {
342 if (block == null || this.member == this.block.content.size()){
343 return false;
344 }
345 return true;
346 }
347}
348
349final class HTMLBlockTagEnumerator implements Enumeration
350{
351 private HTMLBlock block;
352 int member;
353
354 public HTMLBlockTagEnumerator(HTMLBlock block)
355 {
356 this.block = block;
357 this.member = 0;
358 while ( this.member < this.block.content.size() &&
359 this.block.content.elementAt(this.member) instanceof HTMLTag == false){
360 this.member ++;
361 }
362 }
363
364 public Object nextElement()
365 {
366 Object element;
367
368 element = this.block.content.elementAt(member);
369 do {
370 member ++;
371 } while (this.block.content.elementAt(member) instanceof HTMLTag == false);
372 return element;
373 }
374
375 public boolean hasMoreElements()
376 {
377 if (block == null || this.member == this.block.content.size()){
378 return false;
379 }
380 return true;
381 }
382}
383
Note: See TracBrowser for help on using the repository browser.