1 /*
2 * $Source: /usr/cvsroot/melati/poem/src/main/java/org/melati/poem/TailoredResultSetEnumeration.java,v $
3 * $Revision: 1.18 $
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 java.sql.SQLException;
49 import java.sql.ResultSet;
50
51 /**
52 * A {@link ResultSetEnumeration} relying on a {@link TailoredQuery}
53 * for column and access information.
54 */
55 public class TailoredResultSetEnumeration<T> extends ResultSetEnumeration<T> {
56
57 protected TailoredQuery query;
58
59 /**
60 * Constructor.
61 * @param query the TailoredQuery
62 * @param resultSet ResultSet to create Enumeration from
63 */
64 public TailoredResultSetEnumeration(TailoredQuery query,
65 ResultSet resultSet) {
66 super(resultSet);
67 this.query = query;
68 }
69
70 /**
71 * Check whether defaultCanRead debars us from reading.
72 * Explicit canRead columns are checked in column(ResultSet them, int c).
73 */
74 void checkTableAccess() {
75 AccessToken token = PoemThread.accessToken();
76
77 for (int t = 0; t < query.tablesWithoutCanReadColumn.length; ++t) {
78 Capability canRead = query.tablesWithoutCanReadColumn[t].getDefaultCanRead();
79 if (canRead != null && !token.givesCapability(canRead))
80 throw new AccessPoemException(token, canRead);
81 }
82 }
83
84 /**
85 * Returns the raw value of a numbered column in the current row
86 * of a result set.
87 *
88 * @param them the ResultSet
89 * @param c index into ResultSet
90 * @return the raw value
91 */
92 Object column(ResultSet them, int c) {
93 Column<?> column = query.columns[c];
94 Object raw = column.getSQLType().getRaw(them, c + 1);
95
96 if (query.isCanReadColumn[c]) {
97 Capability canRead = (Capability)column.getType().cookedOfRaw(raw);
98 if (canRead == null)
99 canRead = column.getTable().getDefaultCanRead();
100 if (canRead != null) {
101 AccessToken token = PoemThread.accessToken();
102 if (!token.givesCapability(canRead))
103 throw new AccessPoemException(token, canRead);
104 }
105 }
106
107 return raw;
108 }
109
110 /**
111 * Return the current result set row packaged with column names in a
112 * {@link FieldSet}.
113 * {@inheritDoc}
114 * @see org.melati.poem.ResultSetEnumeration#mapped(java.sql.ResultSet)
115 */
116 @SuppressWarnings({ "unchecked", "rawtypes" })
117 protected Object mapped(ResultSet them)
118 throws SQLException, NoSuchRowPoemException {
119 checkTableAccess();
120
121 Field<?>[] fields = new Field[query.columns.length];
122 try {
123 for (int c = 0; c < fields.length; ++c)
124 fields[c] = new Field(column(them, c), query.columns[c]);
125 }
126 catch (AccessPoemException accessProblem) {
127 // Blank out the whole FieldSet. We have to do this because we don't
128 // know how fields have been used in the WHERE clause without
129 // interpreting it. Walls have ears and all that.
130
131 for (int c = 0; c < fields.length; ++c)
132 fields[c] = new Field(accessProblem, query.columns[c]);
133 }
134
135 return new FieldSet(query.table_columnMap, fields);
136 }
137 }