| /******************************************************************************* |
| * Copyright (c) 2005, 2009 Andrea Bittau, University College London, 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: |
| * Andrea Bittau - initial API and implementation from the PsychoPath XPath 2.0 |
| *******************************************************************************/ |
| |
| package org.eclipse.wst.xml.xpath2.processor.internal.ast; |
| |
| import java.util.*; |
| |
| /** |
| * A filter expression consists simply of a primary expression followed by zero |
| * or more predicates. The result of the filter expression consists of all the |
| * items returned by the primary expression for which all the predicates are |
| * true. If no predicates are specified, the result is simply the result of the |
| * primary expression. This result may contain nodes, atomic values, or any |
| * combination of these. The ordering of the items returned by a filter |
| * expression is the same as their order in the result of the primary |
| * expression. Context positions are assigned to items based on their ordinal |
| * position in the result sequence. The first context position is 1. |
| */ |
| public class FilterExpr extends StepExpr { |
| private PrimaryExpr _pexpr; |
| private Collection _exprs; |
| |
| /** |
| * Constructor of FilterExpr. |
| * |
| * @param pexpr |
| * is copied to _pexpr. |
| * @param exprs |
| * is copied to _exprs. |
| */ |
| public FilterExpr(PrimaryExpr pexpr, Collection exprs) { |
| _pexpr = pexpr; |
| _exprs = exprs; |
| } |
| |
| /** |
| * Support for Visitor interface. |
| * |
| * @return Result of Visitor operation. |
| */ |
| @Override |
| public Object accept(XPathVisitor v) { |
| return v.visit(this); |
| } |
| |
| /** |
| * Get the primary expression. |
| * |
| * @return The primary expression. |
| */ |
| public PrimaryExpr primary() { |
| return _pexpr; |
| } |
| |
| /** |
| * Get the next predicate. |
| * |
| * @return The next predicate. |
| */ |
| public Iterator iterator() { |
| return _exprs.iterator(); |
| } |
| |
| /** |
| * Set a new primary expression. |
| * |
| * @param e |
| * is set as the new primary expression. |
| */ |
| public void set_primary(PrimaryExpr e) { |
| _pexpr = e; |
| } |
| |
| /** |
| * Count the number of predicates. |
| * |
| * @return The size of the collection of predicates. |
| */ |
| public int predicate_count() { |
| return _exprs.size(); |
| } |
| } |