org.apache.jackrabbit.spi.commons.query.jsr283.qom
Interface QueryObjectModel

All Superinterfaces:

javax.jcr.query.Query

All Known Implementing Classes:

QueryObjectModelImpl

public interface QueryObjectModel
extends javax.jcr.query.Query

A query in the JCR query object model.

The JCR query object model describes the queries that can be evaluated by a JCR repository independent of any particular query language, such as SQL.

A query consists of:

• a source. When the query is evaluated, the source evaluates its selectors and the joins between them to produce a (possibly empty) set of node-tuples. This is a set of 1-tuples if the query has one selector (and therefore no joins), a set of 2-tuples if the query has two selectors (and therefore one join), a set of 3-tuples if the query has three selectors (two joins), and so forth.
• an optional constraint. When the query is evaluated, the constraint filters the set of node-tuples.
• a list of zero or more orderings. The orderings specify the order in which the node-tuples appear in the query results. The relative order of two node-tuples is determined by evaluating the specified orderings, in list order, until encountering an ordering for which one node-tuple precedes the other. If no orderings are specified, or if for none of the specified orderings does one node-tuple precede the other, then the relative order of the node-tuples is implementation determined (and may be arbitrary).
• a list of zero or more columns to include in the tabular view of the query results. If no columns are specified, the columns available in the tabular view are implementation determined, but minimally include, for each selector, a column for each single-valued non-residual property of the selector's node type.

The query object model representation of a query is created by factory methods in the QueryObjectModelFactory.

Since:

JCR 2.0

Field Summary

Fields inherited from interface javax.jcr.query.Query

SQL, XPATH

Method Summary

Column[]	getColumns() Gets the columns for this query.
Constraint	getConstraint() Gets the constraint for this query.
Ordering[]	getOrderings() Gets the orderings for this query.
Source	getSource() Gets the node-tuple source for this query.

Methods inherited from interface javax.jcr.query.Query

execute, getLanguage, getStatement, getStoredQueryPath, storeAsNode

Method Detail

getSource

Source getSource()

Gets the node-tuple source for this query.

Returns:

the node-tuple source; non-null

getConstraint

Constraint getConstraint()

Gets the constraint for this query.

Returns:

the constraint, or null if none

getOrderings

Ordering[] getOrderings()

Gets the orderings for this query.

Returns:

an array of zero or more orderings; non-null

getColumns

Column[] getColumns()

Gets the columns for this query.

Returns:

an array of zero or more columns; non-null