/*
* Copyright 2010 Duraspace.
*
* 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 org.mulgara.query.filter;
import org.mulgara.query.QueryException;
import org.mulgara.query.filter.value.Bool;
/**
* An inversion of a test.
* This is different to NOT in that it will pass if the test fails with an exception.
*
* @created Jan 8, 2010
* @author Paula Gearon
*/
public class Inverse extends AbstractFilterValue implements Filter {
/** Generated Serialization ID for RMI */
private static final long serialVersionUID = -246496920520897841L;
/** The filter to invert. Local storage of operands[0]. */
Filter operand;
/**
* Create an inversion of a filter
* @param operand The filter to invert
*/
public Inverse(Filter operand) {
super(operand);
this.operand = operand;
}
/**
* @see org.mulgara.query.filter.Filter#test(Context)
*/
public boolean test(Context context) throws QueryException {
setCurrentContext(context);
try {
return !operand.test(context);
} catch (QueryException e) {
return true;
}
}
/** @see org.mulgara.query.filter.AbstractFilterValue#resolve() */
protected RDFTerm resolve() throws QueryException {
try {
return operand.test(getCurrentContext()) ? Bool.FALSE : Bool.TRUE;
} catch (QueryException e) {
return Bool.TRUE;
}
}
}