| /******************************************************************************* |
| * Copyright (c) 2009, 2010 Cloudsmith Inc. and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Cloudsmith Inc. - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.equinox.internal.p2.metadata.expression; |
| |
| import java.util.Iterator; |
| import org.eclipse.equinox.p2.metadata.expression.IEvaluationContext; |
| |
| /** |
| * An expression that yields a new collection consisting of all elements of the |
| * <code>collection</code> for which the <code>filter</code> yields <code>true</code>. |
| */ |
| final class Select extends CollectionFilter { |
| Select(Expression collection, LambdaExpression lambda) { |
| super(collection, lambda); |
| } |
| |
| protected Object evaluate(IEvaluationContext context, Iterator<?> itor) { |
| return evaluateAsIterator(context, itor); |
| } |
| |
| protected Iterator<?> evaluateAsIterator(final IEvaluationContext context, Iterator<?> itor) { |
| return new MatchIteratorFilter<Object>(itor) { |
| protected boolean isMatch(Object val) { |
| lambda.getItemVariable().setValue(context, val); |
| return lambda.evaluate(context) == Boolean.TRUE; |
| } |
| }; |
| } |
| |
| public int getExpressionType() { |
| return TYPE_SELECT; |
| } |
| |
| public String getOperator() { |
| return KEYWORD_SELECT; |
| } |
| |
| boolean isCollection() { |
| return true; |
| } |
| } |