01: /**
02: * Copyright 2006 Webmedia Group Ltd.
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
10: * Unless required by applicable law or agreed to in writing, software
11: * distributed under the License is distributed on an "AS IS" BASIS,
12: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13: * See the License for the specific language governing permissions and
14: * limitations under the License.
15: **/package org.araneaframework.backend.list.helper.naming;
16:
17: import org.araneaframework.backend.list.helper.ListSqlHelper;
18:
19: /**
20: * Naming conventions between list fields and database columns.
21: * <p>
22: * Method {@link #fieldToColumnName(String)} converts field names into column names.
23: * Method {@link #fieldToColumnAlias(String)} converts field names into column aliases.
24: *
25: * @see ListSqlHelper#getNamingStrategy()
26: * @see StandardNamingStrategy
27: * @see PrefixMapNamingStrategy
28: * @see MappingNamingStrategyAndFields
29: * @see OrNamingStrategy
30: *
31: * @author Rein Raudjärv
32: *
33: * @since 1.1
34: */
35: public interface NamingStrategy {
36:
37: /**
38: * Converts <b>field name</b> into <b>database column name</b>.
39: * <p>
40: * E.g.<br/>
41: * <code>firstName</code> -> <code>FIRST_NAME</code><br/>
42: * <code>group.name</code> -> <code>G.NAME</code><br/>
43: * <code>name</code> -> <code>FIRSTNAME || " " || LASTNAME</code>
44: * <code>total</code> -> <code>sum(POINTS)</code>
45: *
46: * @param fieldName field name of the list.
47: * @return corresponding database column name used in SQL query.
48: */
49: String fieldToColumnName(String fieldName);
50:
51: /**
52: * Converts <b>field name</b> into <b>database column alias</b>.
53: * <p>
54: * When two or more tables are used in <code>SELECT</code> with
55: * the same column name they must be distinguishable. Thus
56: * each column name must be followed by a unique alias which is
57: * referred later in <code>WHERE</code> and <code>ORDER BY</code>
58: * clause and also in the result set.
59: * </p>
60: * <p>
61: * In <code>ORDER BY</code> expressions cannot be used like
62: * <code>COUNT(points)</code> instead these expressions must be
63: * defined together with aliases in the column list right after
64: * <code>SELECT</code>.
65: * </p>
66: * <p>
67: * An alias must not contain dots neither it can be a SQL expression.
68: * </p>
69: * <p>
70: * E.g.<br/>
71: * <code>description</code> -> <code>DESCRIPTION</code><br/>
72: * <code>mother.firstName</code> -> <code>MOTHER_FIRST_NAME</code><br/>
73: * <code>father.firstName</code> -> <code>FATHER_FIRST_NAME</code><br/>
74: * <code>total</code> -> <code>TOTAL</code><br/>
75: *
76: * @param fieldName field name of the list.
77: * @return corresponding database column alias used in SQL query.
78: */
79: String fieldToColumnAlias(String fieldName);
80:
81: }
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