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1
64
65 package com.jcorporate.expresso.services.html;
66
67 import org.apache.log4j.Logger;
68
69 import java.io.OutputStream  ;
70 import java.io.PrintWriter ;
71 import java.util.Hashtable ;
72 import java.util.Vector ;
73
74
75
81 public abstract class HtmlElement {
82 protected Vector contents = new Vector (5);
83 private String thisClass = (this.getClass().getName() + ".");
84 private HtmlElement myParent = null;
85 private String myObjName = "No Name";
86 private boolean hasBeenDisplayed = false;
87 protected String cSSClass = "jc-default";
88 protected String cSSID = null;
89 protected Hashtable attributes = null;
90 private static Logger log = Logger.getLogger(HtmlElement.class);
91 private static char[] padding = new char[256];
92
93 {
95 for (int i = 0; i < padding.length; i++) {
96 padding[i] = '\t';
97 }
98 }
99
100
105 public HtmlElement()
106 throws HtmlException {
107 super();
108 }
109
110
117 public HtmlElement(HtmlElement newElement)
118 throws HtmlException {
119 super();
120 add(newElement);
121 }
122
123
130 public HtmlElement(String elementName)
131 throws HtmlException {
132 super();
133
134 if (elementName != null) {
135 setName(elementName);
136 } else {
137 setName("null");
138 }
139 }
140
141
147 public synchronized void add(HtmlElement newElement)
148 throws HtmlException {
149 String myName = (thisClass + "add(HtmlElement)");
150
151 if (newElement == null) {
152 throw new HtmlException(myName + ":Cannot add null element to '" +
153 getName() + "'");
154 }
155
156 newElement.setParent(this);
157 contents.addElement(newElement);
158 }
159
160
161
167 protected void display(OutputStream out)
168 throws HtmlException {
169 display(new PrintWriter (out), 0);
170 }
171
172
173
181 protected abstract void display(PrintWriter out, int depth)
182 throws HtmlException;
183
184
185
190 protected void finalize()
191 throws HtmlException {
192 String myName = (thisClass + "finalize()");
193
194 if (!hasBeenDisplayed) {
195 throw new HtmlException(myName + ":WARNING: Object '" + getName() +
196 "' was never displayed!");
197 }
198 }
199
200
201
208 public Object getAttribute(String attribName)
209 throws HtmlException {
210 if (attributes == null) {
211 return null;
212 }
213
214 return attributes.get(attribName);
215 }
216
217
218
223 public int getContentCount() {
224 return contents.size();
225 }
226
227
230 public String getCSSClass() {
231 return cSSClass;
232 }
233
234
241 public String getName()
242 throws HtmlException {
243 String myName = (thisClass + "getName()");
244
245 if (myObjName == null) {
246 myObjName = ("Null Name");
247 }
248 if (myParent == this) {
249 throw new HtmlException(myName + ":Object " + myObjName +
250 " cannot have itself as a parent");
251 }
252
253 return ("<strong>" + myObjName + "</strong>");
254 }
255
256
257
264 protected void padWithTabs(PrintWriter out, int count) {
265 if (count > padding.length) {
266 log.warn("Encountered > " + padding.length +
267 " nesting. Source format will no longer be padded");
268 out.print(new String (padding, 0, count));
269 }
270 }
271
272
279 public synchronized void setAttribute(String attribName,
280 Object attribValue)
281 throws HtmlException {
282 if (attributes == null) {
283 attributes = new Hashtable ();
284 }
285
286 attributes.put(attribName, attribValue);
287 }
288
289
290
293 public void setCSSClass(String className) {
294 cSSClass = className;
295 }
296
297
300 public void setCSSID(String id) {
301 cSSID = id;
302 }
303
304
309 protected void setDisplayed()
310 throws HtmlException {
311 String myName = (thisClass + "setDisplayed()");
312
313 if (hasBeenDisplayed) {
314 throw new HtmlException(myName + ":Element " + getName() +
315 " has already been displayed - cannot display twice");
316 }
317 }
318
319
320
326 public void setName(String newName)
327 throws HtmlException {
328 String myName = (thisClass + "setName(String)");
329
330 if (newName == null) {
331 throw new HtmlException(myName + ":Cannot set name to null");
332 }
333
334 myObjName = newName;
335 }
336
337
338
345 protected void setParent(HtmlElement newParent)
346 throws HtmlException {
347 String myName = (thisClass + "setParent(HtmlElement)");
348
349 if (newParent == null) {
350 throw new HtmlException(myName + ":Can't set parent of " +
351 getName() + " to a null element");
352 }
353 if (myParent != null) {
354 if (newParent == myParent) {
355 throw new HtmlException(myName + ":This element, " +
356 getName() +
357 ", has already been added to the element you are " +
358 "adding it to: " +
359 newParent.getName() +
360 " - cannot add again");
361 } else {
362 throw new HtmlException(myName + ":This element, '" +
363 getName() +
364 "', has already been added to another element:" +
365 myParent.getName() +
366 " - cannot add it to another elements");
367 }
368 }
369
370
371 myParent = newParent;
372 }
373
374 }
375 |
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