| /******************************************************************************* |
| * Copyright (c) 2009 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.ql; |
| |
| import java.util.Iterator; |
| |
| /** |
| * A collection filter that yields the first element of the <code>collection</code> for which |
| * the <code>filter</code> yields <code>true</code> |
| */ |
| public final class First extends CollectionFilter { |
| public static final String OPERATOR = "first"; //$NON-NLS-1$ |
| |
| public First(Expression collection, LambdaExpression lambda) { |
| super(collection, lambda); |
| } |
| |
| Object evaluate(ExpressionContext context, VariableScope scope, Iterator itor) { |
| while (itor.hasNext()) { |
| Object each = itor.next(); |
| variable.setValue(scope, each); |
| if (lambda.evaluate(context, scope) == Boolean.TRUE) |
| return each; |
| } |
| return null; |
| } |
| |
| String getOperator() { |
| return OPERATOR; |
| } |
| } |