1 /*
2  * Copyright (C) 2007 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package org.apache.harmony.xml.dom;
18 
19 import org.w3c.dom.DOMException;
20 import org.w3c.dom.DOMImplementation;
21 import org.w3c.dom.Document;
22 import org.w3c.dom.DocumentType;
23 
24 /**
25  * Provides a straightforward implementation of the corresponding W3C DOM
26  * interface. The class is used internally only, thus only notable members that
27  * are not in the original interface are documented (the W3C docs are quite
28  * extensive). Hope that's ok.
29  * <p>
30  * Some of the fields may have package visibility, so other classes belonging to
31  * the DOM implementation can easily access them while maintaining the DOM tree
32  * structure.
33  */
34 public final class DOMImplementationImpl implements DOMImplementation {
35 
36     // Singleton instance.
37     private static DOMImplementationImpl instance;
38 
DOMImplementationImpl()39     DOMImplementationImpl() {
40     }
41 
createDocument(String namespaceURI, String qualifiedName, DocumentType doctype)42     public Document createDocument(String namespaceURI, String qualifiedName,
43             DocumentType doctype) throws DOMException {
44         return new DocumentImpl(this, namespaceURI, qualifiedName, doctype, null);
45     }
46 
createDocumentType(String qualifiedName, String publicId, String systemId)47     public DocumentType createDocumentType(String qualifiedName,
48             String publicId, String systemId) throws DOMException {
49         return new DocumentTypeImpl(null, qualifiedName, publicId, systemId);
50     }
51 
hasFeature(String feature, String version)52     public boolean hasFeature(String feature, String version) {
53         boolean anyVersion = version == null || version.length() == 0;
54         if (feature.startsWith("+")) {
55             feature = feature.substring(1);
56         }
57 
58         // TODO: fully implement these APIs:
59         // "LS" (org.w3c.dom.ls) versions "3.0"
60         // "ElementTraversal" (org.w3c.dom.traversal) versions "1.0"
61 
62         if (feature.equalsIgnoreCase("Core")) {
63             return anyVersion || version.equals("1.0") || version.equals("2.0") || version.equals("3.0");
64         } else if (feature.equalsIgnoreCase("XML")) {
65             return anyVersion || version.equals("1.0") || version.equals("2.0") || version.equals("3.0");
66         } else if (feature.equalsIgnoreCase("XMLVersion")) {
67             return anyVersion || version.equals("1.0") || version.equals("1.1");
68         } else {
69             return false;
70         }
71     }
72 
73     /**
74      * Requests the singleton instance of the class. Creates it first, if
75      * necessary.
76      *
77      * @return The singleton Android DOMImplementationImpl instance.
78      */
getInstance()79     public static DOMImplementationImpl getInstance() {
80         if (instance == null) {
81             instance = new DOMImplementationImpl();
82         }
83 
84         return instance;
85     }
86 
getFeature(String feature, String version)87     public Object getFeature(String feature, String version) {
88         return hasFeature(feature, version) ? this : null;
89     }
90 }
91