Package liquibase.executor.jvm

Class RowMapperResultSetExtractor

  • Direct Known Subclasses:
    RowMapperNotNullConstraintsResultSetExtractor
    public class RowMapperResultSetExtractor
extends Object
    Adapter implementation of the ResultSetExtractor interface that delegates to a RowMapper which is supposed to create an object for each row. Each object is added to the results List of this ResultSetExtractor.

    Useful for the typical case of one object per row in the database table. The number of entries in the results list will match the number of rows.

    Note that a RowMapper object is typically stateless and thus reusable; just the RowMapperResultSetExtractor adapter is stateful.

    A usage example with JdbcTemplate: 

    JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);  // reusable object
 RowMapper rowMapper = new UserRowMapper();  // reusable object
 
    
 List allUsers = (List) jdbcTemplate.query(
 "select * from user",
 new RowMapperResultSetExtractor(rowMapper, 10));
 
    
 User user = (User) jdbcTemplate.queryForObject(
 "select * from user where id=?", new Object[] {id},
 new RowMapperResultSetExtractor(rowMapper, 1));

    See Also:
    RowMapper, Executor

    • Field Detail

      • rowMapper

        protected final RowMapper rowMapper

      • rowsExpected

        protected final int rowsExpected

    • Constructor Detail

      • RowMapperResultSetExtractor

        public RowMapperResultSetExtractor​(RowMapper rowMapper)
        Create a new RowMapperResultSetExtractor.
        Parameters:
        rowMapper - the RowMapper which creates an object for each row

      • RowMapperResultSetExtractor

        public RowMapperResultSetExtractor​(RowMapper rowMapper,
                                   int rowsExpected)
        Create a new RowMapperResultSetExtractor.
        Parameters:
        rowMapper - the RowMapper which creates an object for each row
        rowsExpected - the number of expected rows (just used for optimized collection handling)