1 /**
2 * Licensed under the Artistic License; you may not use this file
3 * except in compliance with the License.
4 * You may obtain a copy of the License at
5 *
6 * http://displaytag.sourceforge.net/license.html
7 *
8 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
9 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
10 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
11 */
12 package org.displaytag.pagination;
13
14 import java.text.MessageFormat;
15 import java.util.ArrayList;
16 import java.util.Iterator;
17 import java.util.List;
18
19 import org.apache.commons.lang.builder.ToStringBuilder;
20 import org.apache.commons.lang.builder.ToStringStyle;
21 import org.apache.commons.logging.Log;
22 import org.apache.commons.logging.LogFactory;
23 import org.displaytag.util.Href;
24
25
26 /**
27 * Helper class for generation of paging banners.
28 * @author Fabrizio Giustina
29 * @version $Revision: 1081 $ ($Author: fgiust $)
30 */
31 public class Pagination
32 {
33
34 /**
35 * logger.
36 */
37 private static Log log = LogFactory.getLog(Pagination.class);
38
39 /**
40 * Base href for urls.
41 */
42 private Href href;
43
44 /**
45 * page parameter name.
46 */
47 private String pageParam;
48
49 /**
50 * first page.
51 */
52 private Integer firstPage;
53
54 /**
55 * last page.
56 */
57 private Integer lastPage;
58
59 /**
60 * previous page.
61 */
62 private Integer previousPage;
63
64 /**
65 * next page.
66 */
67 private Integer nextPage;
68
69 /**
70 * current page.
71 */
72 private Integer currentPage;
73
74 /**
75 * List containg NumberedPage objects.
76 * @see org.displaytag.pagination.NumberedPage
77 */
78 private List pages = new ArrayList();
79
80 /**
81 * Constructor for Pagination.
82 * @param baseHref Href used for links
83 * @param pageParameter name for the page parameter
84 */
85 public Pagination(Href baseHref, String pageParameter)
86 {
87 this.href = baseHref;
88 this.pageParam = pageParameter;
89 }
90
91 /**
92 * Adds a page.
93 * @param number int page number
94 * @param isSelected is the page selected?
95 */
96 public void addPage(int number, boolean isSelected)
97 {
98 if (log.isDebugEnabled())
99 {
100 log.debug("adding page " + number);
101 }
102 this.pages.add(new NumberedPage(number, isSelected));
103 }
104
105 /**
106 * first page selected?
107 * @return boolean
108 */
109 public boolean isFirst()
110 {
111 return this.firstPage == null;
112 }
113
114 /**
115 * last page selected?
116 * @return boolean
117 */
118 public boolean isLast()
119 {
120 return this.lastPage == null;
121 }
122
123 /**
124 * only one page?
125 * @return boolean
126 */
127 public boolean isOnePage()
128 {
129 return (this.pages == null) || this.pages.size() <= 1;
130 }
131
132 /**
133 * Gets the number of the first page.
134 * @return Integer number of the first page
135 */
136 public Integer getFirst()
137 {
138 return this.firstPage;
139 }
140
141 /**
142 * Sets the number of the first page.
143 * @param first Integer number of the first page
144 */
145 public void setFirst(Integer first)
146 {
147 this.firstPage = first;
148 }
149
150 /**
151 * Gets the number of the last page.
152 * @return Integer number of the last page
153 */
154 public Integer getLast()
155 {
156 return this.lastPage;
157 }
158
159 /**
160 * Sets the number of the last page.
161 * @param last Integer number of the last page
162 */
163 public void setLast(Integer last)
164 {
165 this.lastPage = last;
166 }
167
168 /**
169 * Gets the number of the previous page.
170 * @return Integer number of the previous page
171 */
172 public Integer getPrevious()
173 {
174 return this.previousPage;
175 }
176
177 /**
178 * Sets the number of the previous page.
179 * @param previous Integer number of the previous page
180 */
181 public void setPrevious(Integer previous)
182 {
183 this.previousPage = previous;
184 }
185
186 /**
187 * Gets the number of the next page.
188 * @return Integer number of the next page
189 */
190 public Integer getNext()
191 {
192 return this.nextPage;
193 }
194
195 /**
196 * Sets the number of the next page.
197 * @param next Integer number of the next page
198 */
199 public void setNext(Integer next)
200 {
201 this.nextPage = next;
202 }
203
204 /**
205 * Sets the number of the current page.
206 * @param current number of the current page
207 */
208 public void setCurrent(Integer current)
209 {
210 this.currentPage = current;
211 }
212
213 /**
214 * Returns the appropriate banner for the pagination.
215 * @param numberedPageFormat String to be used for a not selected page
216 * @param numberedPageSelectedFormat String to be used for a selected page
217 * @param numberedPageSeparator separator beetween pages
218 * @param fullBanner String basic banner
219 * @return String formatted banner whith pages
220 */
221 public String getFormattedBanner(String numberedPageFormat, String numberedPageSelectedFormat,
222 String numberedPageSeparator, String fullBanner)
223 {
224 StringBuffer buffer = new StringBuffer(100);
225
226 // numbered page list
227 Iterator pageIterator = this.pages.iterator();
228
229 while (pageIterator.hasNext())
230 {
231
232 // get NumberedPage from iterator
233 NumberedPage page = (NumberedPage) pageIterator.next();
234
235 Integer pageNumber = new Integer(page.getNumber());
236
237 String urlString = ((Href) this.href.clone()).addParameter(this.pageParam, pageNumber).toString();
238
239 // needed for MessageFormat : page number/url
240 Object[] pageObjects = {pageNumber, urlString};
241
242 // selected page need a different formatter
243 if (page.getSelected())
244 {
245 buffer.append(MessageFormat.format(numberedPageSelectedFormat, pageObjects));
246 }
247 else
248 {
249 buffer.append(MessageFormat.format(numberedPageFormat, pageObjects));
250 }
251
252 // next? add page separator
253 if (pageIterator.hasNext())
254 {
255 buffer.append(numberedPageSeparator);
256 }
257 }
258
259 // String for numbered pages
260 String numberedPageString = buffer.toString();
261 // Object array
262 // {0} full String for numbered pages
263 // {1} first page url
264 // {2} previous page url
265 // {3} next page url
266 // {4} last page url
267 // {5} current page
268 // {6} total pages
269 Object[] pageObjects = {
270 numberedPageString,
271 ((Href) this.href.clone()).addParameter(this.pageParam, getFirst()),
272 ((Href) this.href.clone()).addParameter(this.pageParam, getPrevious()),
273 ((Href) this.href.clone()).addParameter(this.pageParam, getNext()),
274 ((Href) this.href.clone()).addParameter(this.pageParam, getLast()),
275 this.currentPage,
276 this.isLast() ? this.currentPage : this.lastPage}; // this.lastPage is null if the last page is displayed
277
278 // return the full banner
279 return MessageFormat.format(fullBanner, pageObjects);
280 }
281
282 /**
283 * @see java.lang.Object#toString()
284 */
285 public String toString()
286 {
287 return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE) //
288 .append("firstPage", this.firstPage) //$NON-NLS-1$
289 .append("lastPage", this.lastPage) //$NON-NLS-1$
290 .append("currentPage", this.currentPage) //$NON-NLS-1$
291 .append("nextPage", this.nextPage) //$NON-NLS-1$
292 .append("previousPage", this.previousPage) //$NON-NLS-1$
293 .append("pages", this.pages) //$NON-NLS-1$
294 .append("href", this.href) //$NON-NLS-1$
295 .append("pageParam", this.pageParam) //$NON-NLS-1$
296 .toString();
297 }
298 }
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