| package org.apache.xalan.templates; |
| |
| import java.util.Vector; |
| |
| import org.apache.xml.utils.QName; |
| import org.apache.xpath.ExpressionOwner; |
| import org.apache.xpath.XPathVisitor; |
| import org.apache.xpath.operations.Variable; |
| |
| /** |
| * This class visits variable refs in an XPath and collects their QNames. |
| */ |
| public class VarNameCollector extends XPathVisitor |
| { |
| Vector m_refs = new Vector(); |
| |
| /** |
| * Reset the list for a fresh visitation and collection. |
| */ |
| public void reset() |
| { |
| m_refs.clear(); |
| } |
| |
| /** |
| * Get the number of variable references that were collected. |
| * @return the size of the list. |
| */ |
| public int getVarCount() |
| { |
| return m_refs.size(); |
| } |
| |
| /** |
| * Tell if the given qualified name occurs in |
| * the list of qualified names collected. |
| * |
| * @param refName Must be a valid qualified name. |
| * @return true if the list contains the qualified name. |
| */ |
| boolean doesOccur(QName refName) |
| { |
| return m_refs.contains(refName); |
| } |
| |
| /** |
| * Visit a variable reference. |
| * @param owner The owner of the expression, to which the expression can |
| * be reset if rewriting takes place. |
| * @param var The variable reference object. |
| * @return true if the sub expressions should be traversed. |
| */ |
| public boolean visitVariableRef(ExpressionOwner owner, Variable var) |
| { |
| m_refs.addElement(var.getQName()); |
| return true; |
| } |
| |
| } |
| |