http://jdbi.org/: jdbi is designed to provide convenient tabular data access in Java(tm). It uses the Java collections framework for query results, provides a convenient means of externalizing sql statements, and provides named parameter support for any database being used. 
/*
 * 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.sql.ResultSet;
import java.sql.SQLException;

import org.jdbi.v3.core.statement.StatementContext;


Maps result set rows to objects.

Type parameters:
  • <T> – the mapped type.
See Also:
/**
 * 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(java.lang.reflect.Type, RowMapper)
 */
@FunctionalInterface
public interface RowMapper<T> {
    
Map the current row of the result set.
This method should not cause the result set to advance; allow Jdbi to do that, please.

Params:
  • rs –  the result set being iterated
  • ctx – the statement context
Throws:
  • SQLException – if anything goes wrong go ahead and let this percolate; Jdbi will handle it
Returns:the value to produce for this row
/**
     * Map the current row of the result set.
     * 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 produce 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.


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.

 Implementing this method is optional; the default implementation returns 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. 
Params:
  • rs –  the result set to specialize over
  • ctx – the statement context to specialize over
Throws:
  • SQLException – if anything goes wrong go ahead and let this percolate; Jdbi will handle it
See Also:
Returns:a row mapper equivalent to this one, possibly specialized.
/**
     * 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;
    }
}