Java tutorial
/* * Copyright 2002-2018 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.jdbc.core.namedparam; import java.util.Arrays; import java.util.Collection; import java.util.HashMap; import java.util.Map; import org.springframework.jdbc.core.SqlParameterValue; import org.springframework.lang.Nullable; /** * Class that provides helper methods for the use of {@link SqlParameterSource}, * in particular with {@link NamedParameterJdbcTemplate}. * * @author Thomas Risberg * @author Juergen Hoeller * @since 2.5 */ public abstract class SqlParameterSourceUtils { /** * Create an array of {@link SqlParameterSource} objects populated with data * from the values passed in (either a {@link Map} or a bean object). * This will define what is included in a batch operation. * @param candidates object array of objects containing the values to be used * @return an array of {@link SqlParameterSource} * @see MapSqlParameterSource * @see BeanPropertySqlParameterSource * @see NamedParameterJdbcTemplate#batchUpdate(String, SqlParameterSource[]) */ @SuppressWarnings("unchecked") public static SqlParameterSource[] createBatch(Object... candidates) { return createBatch(Arrays.asList(candidates)); } /** * Create an array of {@link SqlParameterSource} objects populated with data * from the values passed in (either a {@link Map} or a bean object). * This will define what is included in a batch operation. * @param candidates collection of objects containing the values to be used * @return an array of {@link SqlParameterSource} * @since 5.0.2 * @see MapSqlParameterSource * @see BeanPropertySqlParameterSource * @see NamedParameterJdbcTemplate#batchUpdate(String, SqlParameterSource[]) */ @SuppressWarnings("unchecked") public static SqlParameterSource[] createBatch(Collection<?> candidates) { SqlParameterSource[] batch = new SqlParameterSource[candidates.size()]; int i = 0; for (Object candidate : candidates) { batch[i] = (candidate instanceof Map ? new MapSqlParameterSource((Map<String, ?>) candidate) : new BeanPropertySqlParameterSource(candidate)); i++; } return batch; } /** * Create an array of {@link MapSqlParameterSource} objects populated with data from * the values passed in. This will define what is included in a batch operation. * @param valueMaps array of {@link Map} instances containing the values to be used * @return an array of {@link SqlParameterSource} * @see MapSqlParameterSource * @see NamedParameterJdbcTemplate#batchUpdate(String, Map[]) */ public static SqlParameterSource[] createBatch(Map<String, ?>[] valueMaps) { SqlParameterSource[] batch = new SqlParameterSource[valueMaps.length]; for (int i = 0; i < valueMaps.length; i++) { batch[i] = new MapSqlParameterSource(valueMaps[i]); } return batch; } /** * Create a wrapped value if parameter has type information, plain object if not. * @param source the source of parameter values and type information * @param parameterName the name of the parameter * @return the value object */ @Nullable public static Object getTypedValue(SqlParameterSource source, String parameterName) { int sqlType = source.getSqlType(parameterName); if (sqlType != SqlParameterSource.TYPE_UNKNOWN) { if (source.getTypeName(parameterName) != null) { return new SqlParameterValue(sqlType, source.getTypeName(parameterName), source.getValue(parameterName)); } else { return new SqlParameterValue(sqlType, source.getValue(parameterName)); } } else { return source.getValue(parameterName); } } /** * Create a Map of case insensitive parameter names together with the original name. * @param parameterSource the source of parameter names * @return the Map that can be used for case insensitive matching of parameter names */ public static Map<String, String> extractCaseInsensitiveParameterNames(SqlParameterSource parameterSource) { Map<String, String> caseInsensitiveParameterNames = new HashMap<>(); String[] paramNames = parameterSource.getParameterNames(); if (paramNames != null) { for (String name : paramNames) { caseInsensitiveParameterNames.put(name.toLowerCase(), name); } } return caseInsensitiveParameterNames; } }