001    /*****************************************************************************
002     * Copyright (C) PicoContainer Organization. All rights reserved.            *
003     * ------------------------------------------------------------------------- *
004     * The software in this package is published under the terms of the BSD      *
005     * style license a copy of which has been included with this distribution in *
006     * the LICENSE.txt file.                                                     *
007     *****************************************************************************/
008    
009    package org.picocontainer.gems.constraints;
010    
011    import org.picocontainer.ComponentAdapter;
012    import org.picocontainer.PicoVisitor;
013    import org.picocontainer.defaults.CollectionComponentParameter;
014    
015    /**
016     * Constraint that collects/aggregates dependencies to as many components
017     * that satisfy the given constraint.
018     *
019     * @author Nick Sieger
020     * @author Jörg Schaible
021     * @version 1.1
022     */
023    public class CollectionConstraint extends CollectionComponentParameter implements Constraint {
024        protected Constraint constraint;
025    
026        public CollectionConstraint(Constraint constraint) {
027            this(constraint, false);
028        }
029    
030        public CollectionConstraint(Constraint constraint, boolean emptyCollection) {
031            super(Object.class, emptyCollection);
032            this.constraint = constraint;
033        }
034    
035        public boolean evaluate(ComponentAdapter adapter) {
036            return constraint.evaluate(adapter);
037        }
038    
039        public void accept(PicoVisitor visitor) {
040            super.accept(visitor);
041            constraint.accept(visitor);
042        }
043    }