001/*
002 * Copyright 2015-2022 Transmogrify LLC, 2022-2026 Revetware LLC.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.pyranid;
018
019import org.jspecify.annotations.NonNull;
020
021import javax.annotation.concurrent.ThreadSafe;
022import java.sql.PreparedStatement;
023import java.sql.SQLException;
024
025/**
026 * Enables {@link java.sql.PreparedStatement} parameter binding customization via {@link PreparedStatementBinder}.
027 *
028 * @author <a href="https://www.revetkn.com">Mark Allen</a>
029 * @since 3.0.0
030 */
031public interface CustomParameterBinder {
032        /**
033         * Performs custom binding of a {@link PreparedStatement} value given a {@code value} and its {@code index} when {@link #appliesTo(TargetType)} is {@code true}.
034         * <p>
035         * This function is only invoked when {@code parameter} is non-null.
036         *
037         * @param statementContext  current SQL context
038         * @param preparedStatement the prepared statement to bind to
039         * @param parameterIndex    1-based parameter index at which to perform the binding
040         * @param parameter         the parameter to bind at the specified index
041         * @return {@link BindingResult#handled()} if the custom binding was performed, or {@link BindingResult#fallback()} to fall back to default {@link PreparedStatementBinder} behavior
042         * @throws SQLException if an error occurs during binding
043         */
044        @NonNull
045        BindingResult bind(@NonNull StatementContext<?> statementContext,
046                                                                                 @NonNull PreparedStatement preparedStatement,
047                                                                                 @NonNull Integer parameterIndex,
048                                                                                 @NonNull Object parameter) throws SQLException;
049
050        /**
051         * Performs custom binding of a null value given its {@code index} and {@code targetType}.
052         * <p>
053         * This function is only invoked for {@link TypedParameter} values that are {@code null}.
054         *
055         * @param statementContext  current SQL context
056         * @param preparedStatement the prepared statement to bind to
057         * @param parameterIndex    1-based parameter index at which to perform the binding
058         * @param targetType        explicit target type from {@link TypedParameter}
059         * @param sqlType           JDBC SQL type hint (may be {@link java.sql.Types#NULL})
060         * @return {@link BindingResult#handled()} if the custom binding was performed, or {@link BindingResult#fallback()} to fall back to default behavior
061         * @throws SQLException if an error occurs during binding
062         */
063        @NonNull
064        default BindingResult bindNull(@NonNull StatementContext<?> statementContext,
065                                                                                                                                 @NonNull PreparedStatement preparedStatement,
066                                                                                                                                 @NonNull Integer parameterIndex,
067                                                                                                                                 @NonNull TargetType targetType,
068                                                                                                                                 @NonNull Integer sqlType) throws SQLException {
069                return BindingResult.fallback();
070        }
071
072        /**
073         * Specifies which types this custom binder should handle.
074         * <p>
075         * For example, if this binder should apply when binding {@code MyCustomType}, this method could return {@code targetType.matchesClass(MyCustomType.class)}.
076         * <p>
077         * For parameterized types like {@code List<UUID>}, this method could return {@code targetType.matchesParameterizedType(List.class, UUID.class)}.
078         *
079         * @param targetType the target type to evaluate - should this custom binder handle it or not?
080         * @return {@code true} if this binder should handle the type, {@code false} otherwise.
081         */
082        @NonNull
083        Boolean appliesTo(@NonNull TargetType targetType);
084
085        /**
086         * Result of a custom parameter binding attempt.
087         * <p>
088         * Use {@link #handled()} to indicate a successfully-bound value or {@link #fallback()} to indicate "didn't bind; fall back to the registered {@link PreparedStatementBinder} behavior".</p>
089         */
090        @ThreadSafe
091        sealed abstract class BindingResult permits BindingResult.Handled, BindingResult.Fallback {
092                private BindingResult() {}
093
094                /**
095                 * Indicates that this mapper successfully bound a custom value.
096                 *
097                 * @return a result which indicates that this binder successfully bound a custom value
098                 */
099                @NonNull
100                public static BindingResult handled() {
101                        return Handled.INSTANCE;
102                }
103
104                /**
105                 * Indicates that this mapper did not bind a custom value and prefers to fall back to the behavior of the registered {@link PreparedStatementBinder}.
106                 *
107                 * @return a result which indicates that this binder did not bind a custom value
108                 */
109                @NonNull
110                public static BindingResult fallback() {
111                        return Fallback.INSTANCE;
112                }
113
114                @ThreadSafe
115                static final class Handled extends BindingResult {
116                        static final Handled INSTANCE = new Handled();
117
118                        private Handled() {}
119                }
120
121                @ThreadSafe
122                static final class Fallback extends BindingResult {
123                        static final Fallback INSTANCE = new Fallback();
124
125                        private Fallback() {}
126                }
127        }
128}