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1   /*
2    * $Source: /usr/cvsroot/melati/poem/src/main/java/org/melati/poem/ValueInfo.java,v $
3    * $Revision: 1.17 $
4    *
5    * Copyright (C) 2000 William Chesters
6    *
7    * Part of Melati (http://melati.org), a framework for the rapid
8    * development of clean, maintainable web applications.
9    *
10   * Melati is free software; Permission is granted to copy, distribute
11   * and/or modify this software under the terms either:
12   *
13   * a) the GNU General Public License as published by the Free Software
14   *    Foundation; either version 2 of the License, or (at your option)
15   *    any later version,
16   *
17   *    or
18   *
19   * b) any version of the Melati Software License, as published
20   *    at http://melati.org
21   *
22   * You should have received a copy of the GNU General Public License and
23   * the Melati Software License along with this program;
24   * if not, write to the Free Software Foundation, Inc.,
25   * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the
26   * GNU General Public License and visit http://melati.org to obtain the
27   * Melati Software License.
28   *
29   * Feel free to contact the Developers of Melati (http://melati.org),
30   * if you would like to work out a different arrangement than the options
31   * outlined here.  It is our intention to allow Melati to be used by as
32   * wide an audience as possible.
33   *
34   * This program is distributed in the hope that it will be useful,
35   * but WITHOUT ANY WARRANTY; without even the implied warranty of
36   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
37   * GNU General Public License for more details.
38   *
39   * Contact details for copyright holder:
40   *
41   *     William Chesters <williamc At paneris.org>
42   *     http://paneris.org/~williamc
43   *     Obrechtstraat 114, 2517VX Den Haag, The Netherlands
44   */
45  
46  package org.melati.poem;
47  
48  import org.melati.poem.generated.ValueInfoBase;
49  
50  /**
51   * Abstract persistent generated from Poem.dsd
52   * and extended to cover {@link Setting} and {@link ColumnInfo}.
53   *
54   * Melati POEM generated, programmer modifiable stub 
55   * for a <code>Persistent</code> <code>ValueInfo</code> object.
56   * 
57   * 
58   * <table> 
59   * <tr><th colspan='3'>
60   * Field summary for SQL table <code>ValueInfo</code>
61   * </th></tr>
62   * <tr><th>Name</th><th>Type</th><th>Description</th></tr>
63   * <tr><td> displayname </td><td> String </td><td> A user-friendly name for 
64   * the field </td></tr> 
65   * <tr><td> description </td><td> String </td><td> A brief description of the 
66   * field's function </td></tr> 
67   * <tr><td> usereditable </td><td> Boolean </td><td> Whether it makes sense 
68   * for the user to update the field's value </td></tr> 
69   * <tr><td> typefactory </td><td> PoemTypeFactory </td><td> The field's 
70   * Melati type </td></tr> 
71   * <tr><td> nullable </td><td> Boolean </td><td> Whether the field can be 
72   * empty </td></tr> 
73   * <tr><td> size </td><td> Integer </td><td> For character fields, the 
74   * maximum number of characters that can be stored, (-1 for unlimited) 
75   * </td></tr> 
76   * <tr><td> width </td><td> Integer </td><td> A sensible width for text boxes 
77   * used for entering the field, where appropriate </td></tr> 
78   * <tr><td> height </td><td> Integer </td><td> A sensible height for text 
79   * boxes used for entering the field, where appropriate </td></tr> 
80   * <tr><td> precision </td><td> Integer </td><td> Precision (total number of 
81   * digits) for fixed-point numbers </td></tr> 
82   * <tr><td> scale </td><td> Integer </td><td> Scale (number of digits after 
83   * the decimal) for fixed-point numbers </td></tr> 
84   * <tr><td> renderinfo </td><td> String </td><td> The name of the Melati 
85   * templet (if not the default) to use for input controls for the field 
86   * </td></tr> 
87   * <tr><td> rangelow_string </td><td> String </td><td> The low end of the 
88   * range of permissible values for the field </td></tr> 
89   * <tr><td> rangelimit_string </td><td> String </td><td> The (exclusive) 
90   * limit of the range of permissible values for the field </td></tr> 
91   * </table> 
92   * 
93   * @generator org.melati.poem.prepro.TableDef#generateMainJava 
94   */
95  public class ValueInfo extends ValueInfoBase {
96  
97   /**
98    * Constructor 
99    * for a <code>Persistent</code> <code>ValueInfo</code> object.
100   * 
101   * @generator org.melati.poem.prepro.TableDef#generateMainJava 
102   */
103   public ValueInfo() { }
104 
105   // programmer's domain-specific code here
106 
107   /**
108    * @return a Type Parameter based upon our size and nullability 
109    */
110   public PoemTypeFactory.Parameter toTypeParameter() {
111     final Boolean nullableL = getNullable_unsafe();
112     final Integer sizeL = getSize_unsafe();
113     return
114         new PoemTypeFactory.Parameter() {
115           public boolean getNullable() {
116             return nullableL == null || nullableL.booleanValue();
117           }
118 
119           public int getSize() {
120             return sizeL == null ? -1 : sizeL.intValue();
121           }
122         };
123   }
124 
125   private SQLPoemType poemType = null;
126 
127   /**
128    * NOTE A type cannot be changed once initialised.
129    * @return our SQLPoemType
130    */
131   public SQLPoemType getType() {
132     if (poemType == null) {
133       PoemTypeFactory f = getTypefactory();
134 
135       if (f == null) {
136         // this can happen before we have been fully initialised
137         // it's convenient to return the "most general" type available ...
138         return StringPoemType.nullableInstance;
139       }
140       poemType = f.typeOf(getDatabase(), toTypeParameter());
141     }
142 
143     return poemType;
144   }
145 
146   /**
147    * @param nullableP whether nullable
148    * @return A type
149    */
150   private SQLPoemType getRangeEndType(boolean nullableP) {
151     // FIXME a little inefficient, but rarely used; also relies on BasePoemType
152     // should have interface for ranged type ...
153 
154     SQLPoemType t = getType();
155 
156     if (t instanceof BasePoemType) {
157       BasePoemType unrangedType = (BasePoemType)((BasePoemType)t).clone();
158       unrangedType.setRawRange(null, null);
159       return (SQLPoemType)unrangedType.withNullable(nullableP);
160     }
161     else
162       return null;
163   }
164 
165   private FieldAttributes fieldAttributesRenamedAs(FieldAttributes c,
166                                                    PoemType type) {
167     return new BaseFieldAttributes(
168         c.getName(), c.getDisplayName(), c.getDescription(), type,
169         width == null ? 12 : width.intValue(),
170         height == null ? 1 : height.intValue(),
171         renderinfo,
172         false, // indexed
173         usereditable == null ? true : usereditable.booleanValue(),
174         true // usercreateable
175     );
176   }
177 
178   /**
179    * @param c a FieldAttributes eg a Field
180    * @return a new FieldAttributes
181    */
182   public FieldAttributes fieldAttributesRenamedAs(FieldAttributes c) {
183     return fieldAttributesRenamedAs(c, getType());
184   }
185 
186   /**
187    * @param c a Column with a Range
188    * @return a Field representing the end of the Range
189    */
190   private Field rangeEndField(Column c) {
191     SQLPoemType unrangedType = getRangeEndType(c.getType().getNullable());
192 
193     if (unrangedType == null)
194       return null;
195     else {
196       Object raw;
197       try {
198         raw = unrangedType.rawOfString((String)c.getRaw_unsafe(this));
199       }
200       catch (Exception e) {
201         c.setRaw_unsafe(this, null);
202         raw = null;
203         throw new AppBugPoemException("Found a bad entry for " + c + " in " +
204                 getTable().getName() + "/" + troid() + ": " +
205                 "solution is to null it out ...", e);
206       }
207 
208       return new Field(
209           raw,
210           fieldAttributesRenamedAs(c, unrangedType));
211     }
212   }
213 
214   /**
215    * {@inheritDoc}
216    * @see org.melati.poem.generated.ValueInfoBase#getRangelow_stringField()
217    */
218   public Field getRangelow_stringField() {
219     Field it = rangeEndField(getValueInfoTable().getRangelow_stringColumn());
220     return it != null ? it : super.getRangelow_stringField();
221   }
222 
223   /**
224    * {@inheritDoc}
225    * @see org.melati.poem.generated.ValueInfoBase#getRangelimit_stringField()
226    */
227   public Field getRangelimit_stringField() {
228     Field it = rangeEndField(getValueInfoTable().getRangelimit_stringColumn());
229     return it != null ? it : super.getRangelimit_stringField();
230   }
231 
232   /**
233    * {@inheritDoc}
234    * @see org.melati.poem.generated.ValueInfoBase#setRangelow_string(java.lang.String)
235    */
236   public void setRangelow_string(String value) {
237     boolean nullableL = getValueInfoTable().getRangelow_stringColumn().
238                         getType().getNullable();
239     PoemType unrangedType = getRangeEndType(nullableL);
240     if (unrangedType != null)
241       value = unrangedType.stringOfRaw(unrangedType.rawOfString(value));
242     super.setRangelow_string(value);
243   }
244 
245   /**
246    * {@inheritDoc}
247    * @see org.melati.poem.generated.ValueInfoBase#setRangelimit_string(java.lang.String)
248    */
249   public void setRangelimit_string(String value) {
250     boolean nullableL = getValueInfoTable().getRangelimit_stringColumn().
251                         getType().getNullable();
252     PoemType unrangedType = getRangeEndType(nullableL);
253     if (unrangedType != null)
254       value = unrangedType.stringOfRaw(unrangedType.rawOfString(value));
255     super.setRangelimit_string(value);
256   }
257 }