aoqi@0: /*
aoqi@0:  * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package com.sun.xml.internal.dtdparser;
aoqi@0: 
aoqi@0: 
aoqi@0: /**
aoqi@0:  * This class contains static methods used to determine whether identifiers
aoqi@0:  * may appear in certain roles in XML documents.  Such methods are used
aoqi@0:  * both to parse and to create such documents.
aoqi@0:  *
aoqi@0:  * @author David Brownell
aoqi@0:  * @version 1.1, 00/08/05
aoqi@0:  */
aoqi@0: public class XmlNames {
aoqi@0:     private XmlNames() {
aoqi@0:     }
aoqi@0: 
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns true if the value is a legal XML name.
aoqi@0:      *
aoqi@0:      * @param value the string being tested
aoqi@0:      */
aoqi@0:     public static boolean isName(String value) {
aoqi@0:         if (value == null)
aoqi@0:             return false;
aoqi@0: 
aoqi@0:         char c = value.charAt(0);
aoqi@0:         if (!XmlChars.isLetter(c) && c != '_' && c != ':')
aoqi@0:             return false;
aoqi@0:         for (int i = 1; i < value.length(); i++)
aoqi@0:             if (!XmlChars.isNameChar(value.charAt(i)))
aoqi@0:                 return false;
aoqi@0:         return true;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns true if the value is a legal "unqualified" XML name, as
aoqi@0:      * defined in the XML Namespaces proposed recommendation.
aoqi@0:      * These are normal XML names, except that they may not contain
aoqi@0:      * a "colon" character.
aoqi@0:      *
aoqi@0:      * @param value the string being tested
aoqi@0:      */
aoqi@0:     public static boolean isUnqualifiedName(String value) {
aoqi@0:         if (value == null || value.length() == 0)
aoqi@0:             return false;
aoqi@0: 
aoqi@0:         char c = value.charAt(0);
aoqi@0:         if (!XmlChars.isLetter(c) && c != '_')
aoqi@0:             return false;
aoqi@0:         for (int i = 1; i < value.length(); i++)
aoqi@0:             if (!XmlChars.isNCNameChar(value.charAt(i)))
aoqi@0:                 return false;
aoqi@0:         return true;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns true if the value is a legal "qualified" XML name, as defined
aoqi@0:      * in the XML Namespaces proposed recommendation.  Qualified names are
aoqi@0:      * composed of an optional prefix (an unqualified name), followed by a
aoqi@0:      * colon, and a required "local part" (an unqualified name).  Prefixes are
aoqi@0:      * declared, and correspond to particular URIs which scope the "local
aoqi@0:      * part" of the name.  (This method cannot check whether the prefix of a
aoqi@0:      * name has been declared.)
aoqi@0:      *
aoqi@0:      * @param value the string being tested
aoqi@0:      */
aoqi@0:     public static boolean isQualifiedName(String value) {
aoqi@0:         if (value == null)
aoqi@0:             return false;
aoqi@0: 
aoqi@0:         // [6] QName ::= (Prefix ':')? LocalPart
aoqi@0:         // [7] Prefix ::= NCName
aoqi@0:         // [8] LocalPart ::= NCName
aoqi@0: 
aoqi@0:         int first = value.indexOf(':');
aoqi@0: 
aoqi@0:         // no Prefix, only check LocalPart
aoqi@0:         if (first <= 0)
aoqi@0:             return isUnqualifiedName(value);
aoqi@0: 
aoqi@0:         // Prefix exists, check everything
aoqi@0: 
aoqi@0:         int last = value.lastIndexOf(':');
aoqi@0:         if (last != first)
aoqi@0:             return false;
aoqi@0: 
aoqi@0:         return isUnqualifiedName(value.substring(0, first))
aoqi@0:                 && isUnqualifiedName(value.substring(first + 1));
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * This method returns true if the identifier is a "name token"
aoqi@0:      * as defined in the XML specification.  Like names, these
aoqi@0:      * may only contain "name characters"; however, they do not need
aoqi@0:      * to have letters as their initial characters.  Attribute values
aoqi@0:      * defined to be of type NMTOKEN(S) must satisfy this predicate.
aoqi@0:      *
aoqi@0:      * @param token the string being tested
aoqi@0:      */
aoqi@0:     public static boolean isNmtoken(String token) {
aoqi@0:         int length = token.length();
aoqi@0: 
aoqi@0:         for (int i = 0; i < length; i++)
aoqi@0:             if (!XmlChars.isNameChar(token.charAt(i)))
aoqi@0:                 return false;
aoqi@0:         return true;
aoqi@0:     }
aoqi@0: 
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * This method returns true if the identifier is a "name token" as
aoqi@0:      * defined by the XML Namespaces proposed recommendation.
aoqi@0:      * These are like XML "name tokens" but they may not contain the
aoqi@0:      * "colon" character.
aoqi@0:      *
aoqi@0:      * @param token the string being tested
aoqi@0:      * @see #isNmtoken
aoqi@0:      */
aoqi@0:     public static boolean isNCNmtoken(String token) {
aoqi@0:         return isNmtoken(token) && token.indexOf(':') < 0;
aoqi@0:     }
aoqi@0: }