|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
public interface Query
handle to a node in the query graph.
A node in the query graph can represent multiple
classes, one class or an attribute of a class.
The graph
is automatically extended with attributes of added constraints
(see constrain()
)
and upon calls to
descend()
that request nodes that do not yet exist.
References to joined nodes in the query graph kann be obtained
by "walking" along the nodes of the graph with the method
descend()
.
execute()
evaluates the entire graph against all persistent objects.
execute()
can be called from any Query
node
of the graph. It will return an ObjectSet
filled with
objects of the class/classes that the node, it was called from,
represents.
Method Summary | |
---|---|
Constraint |
constrain(java.lang.Object constraint)
adds a constraint to this node. |
Constraints |
constraints()
returns a Constraints
object that holds an array of all constraints on this node. |
Query |
descend(java.lang.String fieldName)
returns a reference to a descendant node in the query graph. |
ObjectSet |
execute()
executes the Query . |
Query |
orderAscending()
adds an ascending ordering criteria to this node of the query graph. |
Query |
orderDescending()
adds a descending order criteria to this node of the query graph. |
Method Detail |
---|
Constraint constrain(java.lang.Object constraint)
Class
: confine the result to objects of one
class (if the Class
object represents a class)
or to objects implementing a specific interface
(if the Class
object represents an interface).Evaluation
: run
evaluation callbacks against all candidates.
constraint
- the constraint to be added to this Query.
Constraint
a new Constraint
for this
query node or null
for objects implementing the
Evaluation
interface.Constraints constraints()
Constraints
object that holds an array of all constraints on this node.
Constraints
on this query node.ObjectSet execute() throws java.io.IOException, IllegalClassTypeException
Query
.
ObjectSet
- the result of the Query
.
java.io.IOException
IllegalClassTypeException
Query descend(java.lang.String fieldName)
field
- path to the descendant.
Query
nodeQuery orderAscending()
Query
object to allow the chaining of method calls.Query orderDescending()
Query
object to allow the chaining of method calls.
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |