/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package org.apache.axiom.c14n.helpers;
import org.apache.axiom.c14n.omwrapper.interfaces.Attr;
import org.apache.axiom.c14n.utils.Constants;
import java.io.Serializable;
import java.util.Comparator;
/**
* Compares two attributes based on the C14n specification.
* <p/>
* <UL>
* <LI>Namespace nodes have a lesser document order position than attribute
* nodes.
* <LI> An element's namespace nodes are sorted lexicographically by
* local name (the default namespace node, if one exists, has no
* local name and is therefore lexicographically least).
* <LI> An element's attribute nodes are sorted lexicographically with
* namespace URI as the primary key and local name as the secondary
* key (an empty namespace URI is lexicographically least).
* </UL>
*
* @author Christian Geuer-Pollmann <geuerp@apache.org>
*
* modified to work with Axiom wrapper by Saliya Ekanayake (esaliya@gmail.com)
*/
public class AttrCompare implements Comparator, Serializable {
private final static long serialVersionUID = -7113259629930576230L;
private final static int ATTR0_BEFORE_ATTR1 = -1;
private final static int ATTR1_BEFORE_ATTR0 = 1;
private final static String XMLNS = Constants.NamespaceSpecNS;
/**
* Compares two attributes based on the C14n specification.
* <p/>
* <UL>
* <LI>Namespace nodes have a lesser document order position than
* attribute nodes.
* <LI> An element's namespace nodes are sorted lexicographically by
* local name (the default namespace node, if one exists, has no
* local name and is therefore lexicographically least).
* <LI> An element's attribute nodes are sorted lexicographically with
* namespace URI as the primary key and local name as the secondary
* key (an empty namespace URI is lexicographically least).
* </UL>
*
* @param obj0 casted org.apache.axiom.c14n.omwrapper.interfaces.Attr
* @param obj1 casted org.apache.axiom.c14n.omwrapper.interfaces.Attr
* @return returns a negative integer, zero, or a positive integer as
* obj0 is less than, equal to, or greater than obj1
*/
public int compare(Object obj0, Object obj1) {
Attr attr0 = (Attr) obj0;
Attr attr1 = (Attr) obj1;
String namespaceURI0 = attr0.getNamespaceURI();
String namespaceURI1 = attr1.getNamespaceURI();
boolean isNamespaceAttr0 = XMLNS == namespaceURI0;
boolean isNamespaceAttr1 = XMLNS == namespaceURI1;
if (isNamespaceAttr0) {
if (isNamespaceAttr1) {
// both are namespaces
String localname0 = attr0.getLocalName();
String localname1 = attr1.getLocalName();
if (localname0.equals("xmlns")) {
localname0 = "";
}
if (localname1.equals("xmlns")) {
localname1 = "";
}
return localname0.compareTo(localname1);
}
// attr0 is a namespace, attr1 is not
return ATTR0_BEFORE_ATTR1;
}
if (isNamespaceAttr1) {
// attr1 is a namespace, attr0 is not
return ATTR1_BEFORE_ATTR0;
}
// none is a namespace
if (namespaceURI0 == null) {
if (namespaceURI1 == null) {
String name0 = attr0.getName();
String name1 = attr1.getName();
return name0.compareTo(name1);
}
return ATTR0_BEFORE_ATTR1;
}
if (namespaceURI1 == null) {
return ATTR1_BEFORE_ATTR0;
}
int a = namespaceURI0.compareTo(namespaceURI1);
if (a != 0) {
return a;
}
return (attr0.getLocalName()).compareTo(attr1.getLocalName());
}
}