RowMapper (Spring Framework 5.2.12.RELEASE API)

类型参数:
T - the result type
所有已知实现类:
BeanPropertyRowMapper, ColumnMapRowMapper, MappingSqlQueryWithParameters.RowMapperImpl, SingleColumnRowMapper, UpdatableSqlQuery.RowMapperImpl
函数接口:
这是一个函数接口, 因此可用作 lambda 表达式或方法引用的赋值目标。
```
@FunctionalInterface
public interface RowMapper<T>
```
An interface used by JdbcTemplate for mapping rows of a ResultSet on a per-row basis. Implementations of this interface perform the actual work of mapping each row to a result object, but don't need to worry about exception handling. SQLExceptions will be caught and handled by the calling JdbcTemplate.
Typically used either for JdbcTemplate's query methods or for out parameters of stored procedures. RowMapper objects are typically stateless and thus reusable; they are an ideal choice for implementing row-mapping logic in a single place.
Alternatively, consider subclassing MappingSqlQuery from the jdbc.object package: Instead of working with separate JdbcTemplate and RowMapper objects, you can build executable query objects (containing row-mapping logic) in that style.
作者:
Thomas Risberg, Juergen Hoeller
另请参阅:
JdbcTemplate, RowCallbackHandler, ResultSetExtractor, MappingSqlQuery

- 方法概要
  所有方法实例方法抽象方法
  修饰符和类型方法说明
  T mapRow(ResultSet rs, int rowNum)
  Implementations must implement this method to map each row of data in the ResultSet.

- 方法详细资料
  - mapRow
```
@Nullable
T mapRow(ResultSet rs,
         int rowNum)
  throws SQLException
```
    Implementations must implement this method to map each row of data in the ResultSet. This method should not call next() on the ResultSet; it is only supposed to map values of the current row.
    参数:
    rs - the ResultSet to map (pre-initialized for the current row)
    rowNum - the number of the current row
    返回:
    the result object for the current row (may be null)
    抛出:
    SQLException - if an SQLException is encountered getting column values (that is, there's no need to catch SQLException)