1 /*
2 * Copyright 2009-2024 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
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 */
16 package org.apache.ibatis.annotations;
17
18 import java.lang.annotation.Documented;
19 import java.lang.annotation.ElementType;
20 import java.lang.annotation.Repeatable;
21 import java.lang.annotation.Retention;
22 import java.lang.annotation.RetentionPolicy;
23 import java.lang.annotation.Target;
24
25 /**
26 * The annotation that specify a method that provide an SQL for retrieving record(s).
27 * <p>
28 * <b>How to use:</b>
29 *
30 * <pre>{@code
31 * public interface UserMapper {
32 *
33 * @SelectProvider(type = SqlProvider.class, method = "selectById")
34 * User selectById(int id);
35 *
36 * public static class SqlProvider {
37 * public static String selectById() {
38 * return "SELECT id, name FROM users WHERE id = #{id}";
39 * }
40 * }
41 *
42 * }
43 * }</pre>
44 *
45 * @author Clinton Begin
46 */
47 @Documented
48 @Retention(RetentionPolicy.RUNTIME)
49 @Target(ElementType.METHOD)
50 @Repeatable(SelectProvider.List.class)
51 public @interface SelectProvider {
52
53 /**
54 * Specify a type that implements an SQL provider method.
55 *
56 * @return a type that implements an SQL provider method
57 *
58 * @since 3.5.2
59 *
60 * @see #type()
61 */
62 Class<?> value() default void.class;
63
64 /**
65 * Specify a type that implements an SQL provider method.
66 * <p>
67 * This attribute is alias of {@link #value()}.
68 *
69 * @return a type that implements an SQL provider method
70 *
71 * @see #value()
72 */
73 Class<?> type() default void.class;
74
75 /**
76 * Specify a method for providing an SQL.
77 * <p>
78 * Since 3.5.1, this attribute can omit.
79 * <p>
80 * If this attribute omit, the MyBatis will call a method that decide by following rules.
81 * <ul>
82 * <li>If class that specified the {@link #type()} attribute implements the
83 * {@link org.apache.ibatis.builder.annotation.ProviderMethodResolver}, the MyBatis use a method that returned by it.
84 * </li>
85 * <li>If cannot resolve a method by {@link org.apache.ibatis.builder.annotation.ProviderMethodResolver} (= not
86 * implement it or it was returned <code>null</code>), the MyBatis will search and use a fallback method that named
87 * <code>provideSql</code> from specified type.</li>
88 * </ul>
89 *
90 * @return a method name of method for providing an SQL
91 */
92 String method() default "";
93
94 /**
95 * @return A database id that correspond this provider
96 *
97 * @since 3.5.5
98 */
99 String databaseId() default "";
100
101 /**
102 * Returns whether this select affects DB data.<br>
103 * e.g. RETURNING of PostgreSQL or OUTPUT of MS SQL Server.
104 *
105 * @return {@code true} if this select affects DB data; {@code false} if otherwise
106 *
107 * @since 3.5.12
108 */
109 boolean affectData() default false;
110
111 /**
112 * The container annotation for {@link SelectProvider}.
113 *
114 * @author Kazuki Shimizu
115 *
116 * @since 3.5.5
117 */
118 @Documented
119 @Retention(RetentionPolicy.RUNTIME)
120 @Target(ElementType.METHOD)
121 @interface List {
122 SelectProvider[] value();
123 }
124
125 }