/*
* #!
* Ontopia Engine
* #-
* Copyright (C) 2001 - 2013 The Ontopia Project
* #-
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* !#
*/
package net.ontopia.persistence.query.sql;
/**
* INTERNAL: SQL condition: exists. Evaluates to true if the left
* value contains the right value.<p>
*
* An EXISTS condition tests for existence of rows in a subquery.<p>
*/
public class SQLExists implements SQLExpressionIF {
protected SQLExpressionIF expression;
public SQLExists(SQLExpressionIF expression) {
if (expression == null)
throw new NullPointerException("Expression must not be null.");
this.expression = expression;
}
public int getType() {
return EXISTS;
}
public SQLExpressionIF getExpression() {
return expression;
}
public void setExpression(SQLExpressionIF expression) {
this.expression = expression;
}
public String toString() {
return "exists (" + getExpression() + ")";
}
}