public interface IPrimaryKeyConverter
This interface is used by the For component
. When
a primary key converter is available, it is used during the render, and as part of the rewind
phase that processes the form submission.
During rendering, getPrimaryKey(Object)
is invoked for each value. This method is
invoked just before the For's body is rendered. The resulting primary key is written into the
client as a hidden form field.
Likewise, during rewind, getValue(Object)
is invoked for each key, to get back the same
(or equivalent) object. Again, the method is invoked just before the For's body is rendered.
The DefaultPrimaryKeyConverter
uses this relationship between a
For component and its primary key converter to track what the current value being rendered or
rewound is.
Modifier and Type | Method and Description |
---|---|
java.lang.Object |
getPrimaryKey(java.lang.Object value)
Returns the primary key of the given value
|
java.lang.Object |
getValue(java.lang.Object primaryKey)
Returns the value corresponding the given primary key
|
java.lang.Object getPrimaryKey(java.lang.Object value)
objValue
- the value for which a primary key needs to be extractedjava.lang.Object getValue(java.lang.Object primaryKey)
objPrimaryKey
- the primary key for which a value needs to be generated