public interface DCollection
extends java.util.Collection
Collection
interface are supported by an ODMG implementation of DCollection
;
the exception UnsupportedOperationException
is not thrown when a
call is made to any of the Collection
methods.
DCollection
contains methods used to perform queries on the collection.
The OQL query predicate is given as a string with the syntax of the
where
clause of OQL. The predefined OQL variable this
is used inside the predicate to denote the current element of the collection.
Modifier and Type | Method and Description |
---|---|
boolean |
existsElement(java.lang.String predicate)
Determines whether there is an element of the collection that evaluates to true
for the predicate.
|
DCollection |
query(java.lang.String predicate)
Evaluate the boolean query predicate for each element of the collection and
return a new collection that contains each element that evaluated to true.
|
java.util.Iterator |
select(java.lang.String predicate)
Access all of the elements of the collection that evaluate to true for the
provided query predicate.
|
java.lang.Object |
selectElement(java.lang.String predicate)
Selects the single element of the collection for which the provided OQL query
predicate is true.
|
java.lang.Object selectElement(java.lang.String predicate) throws QueryInvalidException
predicate
- An OQL boolean query predicate.QueryInvalidException
- The query predicate is invalid.java.util.Iterator select(java.lang.String predicate) throws QueryInvalidException
predicate
- An OQL boolean query predicate.QueryInvalidException
- The query predicate is invalid.DCollection query(java.lang.String predicate) throws QueryInvalidException
predicate
- An OQL boolean query predicate.QueryInvalidException
- The query predicate is invalid.boolean existsElement(java.lang.String predicate) throws QueryInvalidException
predicate
- An OQL boolean query predicate.QueryInvalidException
- The query predicate is invalid.(C) 2002 - 2005 Apache Software Foundation
All rights reserved. Published under the Apache License 2.0.
http://db.apache.org/ojb
Version: 1.0.4, 2005-12-30