/*
* 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
*
* http://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.jdbi.v3.core.mapper;
import java.lang.reflect.Type;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.jdbi.v3.core.statement.StatementContext;
/**
* Maps result set rows to objects.
*
* @param <T> the mapped type.
* @see RowMappers
* @see RowMapperFactory
* @see org.jdbi.v3.core.result.ResultBearing#map(RowMapper)
* @see org.jdbi.v3.core.config.Configurable#registerRowMapper(RowMapper)
* @see org.jdbi.v3.core.config.Configurable#registerRowMapper(Type, RowMapper)
*/
@FunctionalInterface
public interface RowMapper<T> {
/**
* Map the row the result set is at when passed in. This method should not cause the result
* set to advance; allow Jdbi to do that, please.
*
* @param rs the result set being iterated
* @param ctx the statement context
* @return the value to return for this row
* @throws SQLException if anything goes wrong go ahead and let this percolate; Jdbi will handle it
*/
T map(ResultSet rs, StatementContext ctx) throws SQLException;
/**
* Returns a specialized row mapper, optimized for the given result set.
* <p>
* Before mapping the result set from a SQL statement; Jdbi will first call this method to obtain a specialized
* instance. The returned mapper will then be used to map the result set rows, and discarded.
* <p>
* Implementing this method is optional; the default implementation returns {@code this}. Implementors might choose
* to override this method to improve performance, e.g. by matching up column names to properties once for the
* entire result set, rather than repeating the process for every row.
*
* @param rs the result set to specialize over
* @param ctx the statement context to specialize over
* @return a row mapper equivalent to this one, possibly specialized.
* @throws SQLException if anything goes wrong go ahead and let this percolate; Jdbi will handle it
* @see org.jdbi.v3.core.mapper.reflect.BeanMapper for an example of specialization.
*/
default RowMapper<T> specialize(ResultSet rs, StatementContext ctx) throws SQLException {
return this;
}
}