org.apache.openjpa.jdbc.kernel.exps.Exp Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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package org.apache.openjpa.jdbc.kernel.exps;
import java.util.Map;
import org.apache.openjpa.jdbc.sql.SQLBuffer;
import org.apache.openjpa.jdbc.sql.Select;
import org.apache.openjpa.kernel.exps.Expression;
/**
* An Expression represents a query ready for execution. Generally, it is
* a set of conditions that must be met for the query to be true.
*
* @author Abe White
*/
interface Exp
extends Expression {
/**
* Initialize the expression. This method should recursively
* initialize any sub-expressions or values.
*
* @param contains map of relation paths to the number of times
* the paths appear in a contains() expression;
* used to ensure paths used for contains() within
* the same AND expression used different aliases
*/
ExpState initialize(Select sel, ExpContext ctx, Map contains);
/**
* Append the SQL for this expression to the given buffer. The SQL
* should optionally include any joins this expression needs.
*/
void appendTo(Select sel, ExpContext ctx, ExpState state,
SQLBuffer buf);
/**
* Select just the columns for this expression.
*/
void selectColumns(Select sel, ExpContext ctx, ExpState state,
boolean pks);
}