online.sanen.unabo.template

类 ResultSetExtractor2List<T>

java.lang.Object

online.sanen.unabo.template.ResultSetExtractor2List<T>

所有已实现的接口:

ResultSetExtractor<List<T>>

public class ResultSetExtractor2List<T>
extends Object
implements ResultSetExtractor<List<T>>

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));
 

Alternatively, consider subclassing MappingSqlQuery from the jdbc.object package: Instead of working with separate JdbcTemplate and RowMapper objects, you can have executable query objects (containing row-mapping logic) there.

作者:

LazyToShow
Date: 2018年10月14日
Time: 下午2:33:10

构造器概要

构造器

构造器和说明
ResultSetExtractor2List(RowExtractor<T> rowMapper) Create a new RowMapperResultSetExtractor.
ResultSetExtractor2List(RowExtractor<T> rowMapper, int rowsExpected) Create a new RowMapperResultSetExtractor.

方法概要

限定符和类型	方法和说明
List<T>	extractData(ResultSet rs) Implementations must implement this method to process the entire ResultSet.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

ResultSetExtractor2List

public ResultSetExtractor2List(RowExtractor<T> rowMapper)

Create a new RowMapperResultSetExtractor.

参数:

rowMapper - the RowMapper which creates an object for each row

ResultSetExtractor2List

public ResultSetExtractor2List(RowExtractor<T> rowMapper,
                               int rowsExpected)

Create a new RowMapperResultSetExtractor.

参数:

rowMapper - the RowMapper which creates an object for each row

rowsExpected - the number of expected rows (just used for optimized collection handling)

方法详细资料

extractData

public List<T> extractData(ResultSet rs)
                    throws SQLException

从接口复制的说明: ResultSetExtractor

Implementations must implement this method to process the entire ResultSet.

指定者:

extractData 在接口中 ResultSetExtractor<List<T>>

参数:

rs - ResultSet to extract data from. Implementations should not close this: it will be closed by the calling JdbcTemplate.

返回:

an arbitrary result object, or null if none (the extractor will typically be stateful in the latter case).

抛出:

SQLException - if a SQLException is encountered getting column values or navigating (that is, there's no need to catch SQLException)