Package com.ibatis.sqlmap.engine.mapping.result

Interface ResultObjectFactory

public interface ResultObjectFactory

iBATIS uses an implementation of this interface to create result objects after the execution of a statement. To use, specify your implementation class as the type for the "resultObjectFactory" element in the SqlMapConfig. Any implementation of this interface must have a public no argument constructor. Note that iBATIS makes use of this interface through the ResultObjectFactoryUtil class.

Author:

Jeff Butler

Method Summary

Modifier and Type	Method	Description
Object	createInstance(String statementId, Class clazz)	Returns a new instance of the requested class. iBATIS will call this method in these circumstances: When processing a result set - to create new instances of result objects When processing the output parameters of a stored procedure - to create instances of OUTPUT parameters When processing a nested select - to create instances of parameter objects on the nested select When processing result maps with nested result maps. iBATIS will ask the factory to create an instance of the nested object.
void	setProperty(String name, String value)	Called for each property configured in the SqlMapCong file.

Method Details

createInstance

Object createInstance(String statementId,
 Class clazz)
               throws InstantiationException,
IllegalAccessException

Returns a new instance of the requested class. iBATIS will call this method in these circumstances:

• When processing a result set - to create new instances of result objects
• When processing the output parameters of a stored procedure - to create instances of OUTPUT parameters
• When processing a nested select - to create instances of parameter objects on the nested select
• When processing result maps with nested result maps. iBATIS will ask the factory to create an instance of the nested object. If the nested object is some implementation of java.util.Collection then iBATIS will supply default implementations of the common interfaces if the factory chooses not to create the object. If the embedded object is a java.util.List or java.util.Collection the default behavior is to create an java.util.ArrayList. If the embedded object is a java.util.Set the default behavior is to create a java.util.HashSet .

If you return null from this method, iBATIS will attempt to create in instance of the class with it's normal mechanism. This means that you can selectively choose which objects to create with this interface. In the event that you choose not to create an object, iBATIS will translate some common interfaces to their common implementations. If the requested class is List or Collection iBATIS will create an ArrayList. If the requested class is Set then iBATIS will create a HashSet. But these rules only apply if you choose not to create the object. So you can use this factory to supply custom implementations of those interfaces if you so desire.

Parameters:

statementId - the ID of the statement that generated the call to this method

clazz - the type of object to create

Returns:

a new instance of the specified class. The instance must be castable to the specified class. If you return null, iBATIS will attempt to create the instance using it's normal mechanism.

Throws:

InstantiationException - if the instance cannot be created. If you throw this Exception, iBATIS will throw a runtime exception in response and will end.

IllegalAccessException - if the constructor cannot be accessed. If you throw this Exception, iBATIS will throw a runtime exception in response and will end.

setProperty

void setProperty(String name,
 String value)

Called for each property configured in the SqlMapCong file. All the properties will be set before any call is made to createInstance

Parameters:

name - the name

value - the value