Package org.springframework.jdbc.support

Class GeneratedKeyHolder

java.lang.Object

org.springframework.jdbc.support.GeneratedKeyHolder

All Implemented Interfaces:

KeyHolder

public class GeneratedKeyHolder
extends Object
implements KeyHolder

The standard implementation of the KeyHolder interface, to be used for holding auto-generated keys (as potentially returned by JDBC insert statements).

Create an instance of this class for each insert operation, and pass it to the corresponding JdbcTemplate or SqlUpdate methods.

Since:

1.1

Author:

Thomas Risberg, Juergen Hoeller, Slawomir Dymitrow

Constructor Summary

Constructors

Constructor	Description
GeneratedKeyHolder()	Create a new GeneratedKeyHolder with a default list.
GeneratedKeyHolder(List<Map<String,Object>> keyList)	Create a new GeneratedKeyHolder with a given list.

Method Summary

Modifier and Type	Method	Description
@Nullable Number	getKey()	Retrieve the first item from the first map, assuming that there is just one item and just one map, and that the item is a number.
<T> @Nullable T	getKeyAs(Class<T> keyType)	Retrieve the first item from the first map, assuming that there is just one item and just one map, and that the item is an instance of specified type.
List<Map<String,Object>>	getKeyList()	Return a reference to the List that contains the keys.
@Nullable Map<String,Object>	getKeys()	Retrieve the first map of keys.

Methods inherited from class java.lang.Object

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

Constructor Details

GeneratedKeyHolder

public GeneratedKeyHolder()

Create a new GeneratedKeyHolder with a default list.

GeneratedKeyHolder

public GeneratedKeyHolder(List<Map<String,Object>> keyList)

Create a new GeneratedKeyHolder with a given list.

Parameters:

keyList - a list to hold maps of keys

Method Details

getKey

public @Nullable Number getKey()
                        throws InvalidDataAccessApiUsageException,
DataRetrievalFailureException

Description copied from interface: KeyHolder

Retrieve the first item from the first map, assuming that there is just one item and just one map, and that the item is a number. This is the typical case: a single, numeric generated key.

Keys are held in a List of Maps, where each item in the list represents the keys for each row. If there are multiple columns, then the Map will have multiple entries as well. If this method encounters multiple entries in either the map or the list meaning that multiple keys were returned, then an InvalidDataAccessApiUsageException is thrown.

Specified by:

getKey in interface KeyHolder

Returns:

the generated key as a number

Throws:

InvalidDataAccessApiUsageException - if multiple keys are encountered

DataRetrievalFailureException

See Also:

• KeyHolder.getKeyAs(Class)

getKeyAs

public <T> @Nullable T getKeyAs(Class<T> keyType)
                         throws InvalidDataAccessApiUsageException,
DataRetrievalFailureException

Description copied from interface: KeyHolder

Retrieve the first item from the first map, assuming that there is just one item and just one map, and that the item is an instance of specified type. This is a common case: a single generated key of the specified type.

Keys are held in a List of Maps, where each item in the list represents the keys for each row. If there are multiple columns, then the Map will have multiple entries as well. If this method encounters multiple entries in either the map or the list meaning that multiple keys were returned, then an InvalidDataAccessApiUsageException is thrown.

Specified by:

getKeyAs in interface KeyHolder

Parameters:

keyType - the type of the auto-generated key

Returns:

the generated key as an instance of specified type

Throws:

InvalidDataAccessApiUsageException - if multiple keys are encountered

DataRetrievalFailureException

See Also:

• KeyHolder.getKey()

getKeys

public @Nullable Map<String,Object> getKeys()
                                     throws InvalidDataAccessApiUsageException

Description copied from interface: KeyHolder

Retrieve the first map of keys.

If there are multiple entries in the list (meaning that multiple rows had keys returned), then an InvalidDataAccessApiUsageException is thrown.

Specified by:

getKeys in interface KeyHolder

Returns:

the Map of generated keys for a single row

Throws:

InvalidDataAccessApiUsageException - if keys for multiple rows are encountered

getKeyList

public List<Map<String,Object>> getKeyList()

Description copied from interface: KeyHolder

Return a reference to the List that contains the keys.

Can be used for extracting keys for multiple rows (an unusual case), and also for adding new maps of keys.

Specified by:

getKeyList in interface KeyHolder

Returns:

the List for the generated keys, with each entry representing an individual row through a Map of column names and key values