- /*
- * Copyright 1999-2004 The Apache Software Foundation.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- /*
- * $Id: FunctionDef1Arg.java,v 1.12 2004/02/17 04:34:00 minchau Exp $
- */
- package com.sun.org.apache.xpath.internal.functions;
-
- import com.sun.org.apache.xalan.internal.res.XSLMessages;
- import com.sun.org.apache.xml.internal.dtm.DTM;
- import com.sun.org.apache.xml.internal.utils.XMLString;
- import com.sun.org.apache.xpath.internal.XPathContext;
- import com.sun.org.apache.xpath.internal.objects.XString;
- import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
-
- /**
- * Base class for functions that accept one argument that can be defaulted if
- * not specified.
- * @xsl.usage advanced
- */
- public class FunctionDef1Arg extends FunctionOneArg
- {
-
- /**
- * Execute the first argument expression that is expected to return a
- * nodeset. If the argument is null, then return the current context node.
- *
- * @param xctxt Runtime XPath context.
- *
- * @return The first node of the executed nodeset, or the current context
- * node if the first argument is null.
- *
- * @throws javax.xml.transform.TransformerException if an error occurs while
- * executing the argument expression.
- */
- protected int getArg0AsNode(XPathContext xctxt)
- throws javax.xml.transform.TransformerException
- {
-
- return (null == m_arg0)
- ? xctxt.getCurrentNode() : m_arg0.asNode(xctxt);
- }
-
- /**
- * Tell if the expression is a nodeset expression.
- * @return true if the expression can be represented as a nodeset.
- */
- public boolean Arg0IsNodesetExpr()
- {
- return (null == m_arg0) ? true : m_arg0.isNodesetExpr();
- }
-
- /**
- * Execute the first argument expression that is expected to return a
- * string. If the argument is null, then get the string value from the
- * current context node.
- *
- * @param xctxt Runtime XPath context.
- *
- * @return The string value of the first argument, or the string value of the
- * current context node if the first argument is null.
- *
- * @throws javax.xml.transform.TransformerException if an error occurs while
- * executing the argument expression.
- */
- protected XMLString getArg0AsString(XPathContext xctxt)
- throws javax.xml.transform.TransformerException
- {
- if(null == m_arg0)
- {
- int currentNode = xctxt.getCurrentNode();
- if(DTM.NULL == currentNode)
- return XString.EMPTYSTRING;
- else
- {
- DTM dtm = xctxt.getDTM(currentNode);
- return dtm.getStringValue(currentNode);
- }
-
- }
- else
- return m_arg0.execute(xctxt).xstr();
- }
-
- /**
- * Execute the first argument expression that is expected to return a
- * number. If the argument is null, then get the number value from the
- * current context node.
- *
- * @param xctxt Runtime XPath context.
- *
- * @return The number value of the first argument, or the number value of the
- * current context node if the first argument is null.
- *
- * @throws javax.xml.transform.TransformerException if an error occurs while
- * executing the argument expression.
- */
- protected double getArg0AsNumber(XPathContext xctxt)
- throws javax.xml.transform.TransformerException
- {
-
- if(null == m_arg0)
- {
- int currentNode = xctxt.getCurrentNode();
- if(DTM.NULL == currentNode)
- return 0;
- else
- {
- DTM dtm = xctxt.getDTM(currentNode);
- XMLString str = dtm.getStringValue(currentNode);
- return str.toDouble();
- }
-
- }
- else
- return m_arg0.execute(xctxt).num();
- }
-
- /**
- * Check that the number of arguments passed to this function is correct.
- *
- * @param argNum The number of arguments that is being passed to the function.
- *
- * @throws WrongNumberArgsException if the number of arguments is not 0 or 1.
- */
- public void checkNumberArgs(int argNum) throws WrongNumberArgsException
- {
- if (argNum > 1)
- reportWrongNumberArgs();
- }
-
- /**
- * Constructs and throws a WrongNumberArgException with the appropriate
- * message for this function object.
- *
- * @throws WrongNumberArgsException
- */
- protected void reportWrongNumberArgs() throws WrongNumberArgsException {
- throw new WrongNumberArgsException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_ZERO_OR_ONE, null)); //"0 or 1");
- }
-
- /**
- * Tell if this expression or it's subexpressions can traverse outside
- * the current subtree.
- *
- * @return true if traversal outside the context node's subtree can occur.
- */
- public boolean canTraverseOutsideSubtree()
- {
- return (null == m_arg0) ? false : super.canTraverseOutsideSubtree();
- }
- }