package adql.query.constraint;
/*
* This file is part of ADQLLibrary.
*
* ADQLLibrary is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* ADQLLibrary is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with ADQLLibrary. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2012-2015 - UDS/Centre de Données astronomiques de Strasbourg (CDS),
* Astronomisches Rechen Institute (ARI)
*/
import java.util.NoSuchElementException;
import adql.query.ADQLIterator;
import adql.query.ADQLObject;
import adql.query.TextPosition;
/**
* Lets apply the logical operator NOT on any constraint.
*
* @author Grégory Mantelet (CDS;ARI)
* @version 1.4 (06/2015)
*/
public class NotConstraint implements ADQLConstraint {
private ADQLConstraint constraint;
/** Position of this {@link NotConstraint} in the ADQL query string.
* @since 1.4 */
private TextPosition position = null;
/**
* Builds a NotConstraint just with the constraint on which the logical operator NOT must be applied.
*
* @param constraint The constraint on which NOT must be applied.
*
* @throws NullPointerException If the given constraint is <i>null</i>.
*/
public NotConstraint(ADQLConstraint constraint) throws NullPointerException{
if (constraint == null)
throw new NullPointerException("Impossible to apply the logical operator NOT on a NULL constraint !");
this.constraint = constraint;
}
/**
* Gets the constraint on which the NOT operator is applied.
*
* @return An {@link ADQLConstraint}.
*/
public final ADQLConstraint getConstraint(){
return constraint;
}
@Override
public final TextPosition getPosition(){
return position;
}
/**
* Set the position of this {@link NotConstraint} in the given ADQL query string.
*
* @param position New position of this {@link NotConstraint}.
* @since 1.4
*/
public final void setPosition(final TextPosition position){
this.position = position;
}
@Override
public ADQLObject getCopy() throws Exception{
return new NotConstraint((ADQLConstraint)constraint.getCopy());
}
@Override
public String getName(){
return "NOT " + constraint.getName();
}
@Override
public ADQLIterator adqlIterator(){
return new ADQLIterator(){
private boolean constraintGot = (constraint == null);
@Override
public ADQLObject next(){
if (constraintGot)
throw new NoSuchElementException();
constraintGot = true;
return constraint;
}
@Override
public boolean hasNext(){
return !constraintGot;
}
@Override
public void replace(ADQLObject replacer) throws UnsupportedOperationException, IllegalStateException{
if (!constraintGot)
throw new IllegalStateException("replace(ADQLObject) impossible: next() has not yet been called !");
if (replacer == null)
remove();
else if (replacer instanceof ADQLConstraint){
constraint = (ADQLConstraint)replacer;
position = null;
}else
throw new UnsupportedOperationException("Impossible to replace an ADQLConstraint by a " + replacer.getClass().getName() + " !");
}
@Override
public void remove(){
if (!constraintGot)
throw new IllegalStateException("remove() impossible: next() has not yet been called !");
else
throw new UnsupportedOperationException("Impossible to remove the constraint of a NOT predicated !");
}
};
}
@Override
public String toADQL(){
return "NOT " + constraint.toADQL();
}
}