| /******************************************************************************* |
| * Copyright (c) 2005, 2010 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 |
| * Jesper Steen Moeller - bug 285145 - implement full arity checking |
| * Mukul Gandhi - bug 280798 - PsychoPath support for JDK 1.4 |
| *******************************************************************************/ |
| |
| package org.eclipse.wst.xml.xpath2.processor.internal.function; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| |
| import org.eclipse.wst.xml.xpath2.processor.DynamicError; |
| import org.eclipse.wst.xml.xpath2.processor.ResultSequence; |
| import org.eclipse.wst.xml.xpath2.processor.internal.SeqType; |
| import org.eclipse.wst.xml.xpath2.processor.internal.types.NodeType; |
| import org.eclipse.wst.xml.xpath2.processor.internal.types.QName; |
| |
| /** |
| * Returns an xs:boolean indicating whether the argument node is "nilled". If |
| * the argument is not an element node, returns the empty sequence. |
| */ |
| public class FnNilled extends Function { |
| private static Collection _expected_args = null; |
| |
| /** |
| * Constructor for FnNilled. |
| */ |
| public FnNilled() { |
| super(new QName("nilled"), 0, 1); |
| } |
| |
| /** |
| * Evaluate arguments. |
| * |
| * @param args |
| * argument expressions. |
| * @throws DynamicError |
| * Dynamic error. |
| * @return Result of evaluation. |
| */ |
| public ResultSequence evaluate(Collection args) throws DynamicError { |
| return nilled(args); |
| } |
| |
| /** |
| * Nilled operation. |
| * |
| * @param args |
| * Result from the expressions evaluation. |
| * @throws DynamicError |
| * Dynamic error. |
| * @return Result of fn:nilled operation. |
| */ |
| public static ResultSequence nilled(Collection args) throws DynamicError { |
| |
| Collection cargs = Function.convert_arguments(args, expected_args()); |
| |
| |
| ResultSequence arg1 = (ResultSequence) cargs.iterator().next(); |
| if (arg1.empty()) { |
| return arg1; |
| } |
| NodeType nt = (NodeType) arg1.first(); |
| |
| return nt.nilled(); |
| } |
| |
| /** |
| * Obtain a list of expected arguments. |
| * |
| * @return Result of operation. |
| */ |
| public synchronized static Collection expected_args() { |
| if (_expected_args == null) { |
| _expected_args = new ArrayList(); |
| _expected_args.add(new SeqType(SeqType.OCC_QMARK)); |
| } |
| |
| return _expected_args; |
| } |
| } |