| /******************************************************************************* |
| * 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 |
| * Mukul Gandhi - bug 274471 - improvements to fn:string function (support for arity 0) |
| * Jesper Steen Moeller - bug 285145 - implement full arity checking |
| * Jesper Steen Moller - bug 281938 - handle context and empty sequences correctly |
| * Mukul Gandhi - bug 280798 - PsychoPath support for JDK 1.4 |
| *******************************************************************************/ |
| |
| package org.eclipse.wst.xml.xpath2.processor.internal.function; |
| |
| import java.util.Collection; |
| |
| import org.eclipse.wst.xml.xpath2.api.EvaluationContext; |
| import org.eclipse.wst.xml.xpath2.api.Item; |
| import org.eclipse.wst.xml.xpath2.api.ResultBuffer; |
| import org.eclipse.wst.xml.xpath2.api.ResultSequence; |
| import org.eclipse.wst.xml.xpath2.processor.DynamicError; |
| import org.eclipse.wst.xml.xpath2.processor.internal.TypeError; |
| import org.eclipse.wst.xml.xpath2.processor.internal.types.QName; |
| import org.eclipse.wst.xml.xpath2.processor.internal.types.XSString; |
| |
| /** |
| * Returns the value of $arg represented as a xs:string. If no argument is |
| * supplied, this function returns the string value of the context item (.). |
| */ |
| public class FnString extends Function { |
| /** |
| * Constructor for FnString. |
| */ |
| public FnString() { |
| super(new QName("string"), 0, 1); |
| } |
| |
| /** |
| * Evaluate arguments. |
| * |
| * @param args |
| * argument expressions. |
| * @throws DynamicError |
| * Dynamic error. |
| * @return Result of evaluation. |
| */ |
| public ResultSequence evaluate(Collection args, EvaluationContext ec) throws DynamicError { |
| return string(args, ec); |
| } |
| |
| /** |
| * String operation. |
| * |
| * @param args |
| * Result from the expressions evaluation. |
| * @throws DynamicError |
| * Dynamic error. |
| * @return Result of fn:string operation. |
| */ |
| public static ResultSequence string(Collection args, EvaluationContext ec) throws DynamicError { |
| |
| assert (args.size() == 0 || args.size() == 1); |
| |
| ResultSequence arg1 = null; |
| |
| if (args.isEmpty()) { |
| // support for arity = 0 |
| return getResultSetForArityZero(ec); |
| } |
| else { |
| arg1 = (ResultSequence) args.iterator().next(); |
| } |
| |
| // sanity check args |
| if (arg1.size() > 1) |
| throw new DynamicError(TypeError.invalid_type(null)); |
| |
| ResultBuffer rs = new ResultBuffer(); |
| if (arg1.empty()) { |
| rs.add(new XSString("")); |
| } else { |
| Item at = arg1.first(); |
| rs.add(new XSString(at.getStringValue())); |
| } |
| |
| return rs.getSequence(); |
| } |
| |
| } |