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.parameters.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     */
022    @SuppressWarnings("serial")
023    public final class CollectionConstraint extends CollectionComponentParameter implements Constraint {
024    
025            protected final Constraint constraint;
026    
027        public CollectionConstraint(final Constraint constraint) {
028            this(constraint, false);
029        }
030    
031        public CollectionConstraint(final Constraint constraint, final boolean emptyCollection) {
032            super(Object.class, emptyCollection);
033            this.constraint = constraint;
034        }
035    
036        @Override
037            public boolean evaluate(final ComponentAdapter adapter) {
038            return constraint.evaluate(adapter);
039        }
040    
041        @Override
042            public void accept(final PicoVisitor visitor) {
043            super.accept(visitor);
044            constraint.accept(visitor);
045        }
046    }