code: public NamespaceAlias getNamespaceAliasComposed(String uri)
    {
      return (NamespaceAlias) ((null == m_namespaceAliasComposed) 
                      ? null : m_namespaceAliasComposed.get(uri));
    }
docs: Get the "xsl:namespace-alias" property.
  Return the NamespaceAlias for a given namespace uri.
  @see <a href="http://www.w3.org/TR/xslt#literal-result-element">literal-result-element in XSLT Specification</a>
  
  @param uri non-null reference to namespace that is to be aliased.
  
  @return NamespaceAlias that matches uri, or null if no match.