org.apache.openjpa.jdbc.kernel.exps
Class SelectConstructor

java.lang.Object
  org.apache.openjpa.jdbc.kernel.exps.SelectConstructor

public class SelectConstructor
extends Object

Turns parsed queries into selects.

Author:

Abe White

Constructor Summary

SelectConstructor()

Method Summary

Select	evaluate(ExpContext ctx, Select parent, String alias, QueryExpressions exps, QueryExpressionsState state) Evaluate the expression, returning a new select and filling in any associated expression state.
boolean	isExtent() Return true if we know the select to have on criteria; to be an extent.
void	select(Select sel, ExpContext ctx, ClassMapping mapping, boolean subclasses, QueryExpressions exps, QueryExpressionsState state, int eager) Select the data for this query.

Methods inherited from class java.lang.Object

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

Constructor Detail

SelectConstructor

public SelectConstructor()

Method Detail

isExtent

public boolean isExtent()

Return true if we know the select to have on criteria; to be an extent. Note that even if this method returns false, evaluate(org.apache.openjpa.jdbc.kernel.exps.ExpContext, org.apache.openjpa.jdbc.sql.Select, java.lang.String, org.apache.openjpa.kernel.exps.QueryExpressions, org.apache.openjpa.jdbc.kernel.exps.QueryExpressionsState) may still return null if we haven't cached whether the query is an extent yet.

evaluate

public Select evaluate(ExpContext ctx,
                       Select parent,
                       String alias,
                       QueryExpressions exps,
                       QueryExpressionsState state)

Evaluate the expression, returning a new select and filling in any associated expression state. Use select(org.apache.openjpa.jdbc.sql.Select, org.apache.openjpa.jdbc.kernel.exps.ExpContext, org.apache.openjpa.jdbc.meta.ClassMapping, boolean, org.apache.openjpa.kernel.exps.QueryExpressions, org.apache.openjpa.jdbc.kernel.exps.QueryExpressionsState, int) to then select the data.

Parameters:

ctx - fill with execution context

state - will be filled with expression state

select

public void select(Select sel,
                   ExpContext ctx,
                   ClassMapping mapping,
                   boolean subclasses,
                   QueryExpressions exps,
                   QueryExpressionsState state,
                   int eager)

Select the data for this query.