org.rhq.enterprise.server.util

Class CriteriaQuery<T,C extends org.rhq.core.domain.criteria.BaseCriteria>

java.lang.Object

org.rhq.enterprise.server.util.CriteriaQuery<T,C>

Type Parameters:

T - The return type included by the PageList.

C - The Criteria subclass used to generate/execute the query.

All Implemented Interfaces:

Iterable<T>

public class CriteriaQuery<T,C extends org.rhq.core.domain.criteria.BaseCriteria>
extends Object
implements Iterable<T>

This class provides a way to make PageList results easily iterable with 'for each','while',etc. loops and importantly automatically handles iteration through all PageControl results. This means that with a CriteriaQuery instance once can do: for (Resource entity : query) { and automatically page through all of the results in PageControl.getPageSize(def. 200) chunks.

Author:

John Sanda, Simeon Pinder

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	CriteriaQuery.QueryResultsIterator

Constructor Summary

Constructors

Constructor and Description
CriteriaQuery(C criteria, CriteriaQueryExecutor<T,C> queryExecutor) It is important that the criteria includes sorting.

Method Summary

Methods

Modifier and Type	Method and Description
Iterator<T>	iterator() Returns iterator for a single page of results as defined by i)the Criteria instance ii)the paging details applied to the Criteria instance

Methods inherited from class java.lang.Object

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

Constructor Detail

CriteriaQuery

public CriteriaQuery(C criteria,
             CriteriaQueryExecutor<T,C> queryExecutor)

It is important that the criteria includes sorting. If not then paging is nonsensical as the DB provides no guarantee of ordering. If no sort is specified, an implicit sort on ID is added.

Parameters:

criteria - The criteria applied to each execution of the fetch. If no sort is specified, an implicit sort on ID is added.

queryExecutor -

Method Detail

iterator

public Iterator<T> iterator()

Returns iterator for a single page of results as defined by i)the Criteria instance ii)the paging details applied to the Criteria instance

Specified by:

iterator in interface Iterable<T>