1 /*
2 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.xml.internal.rngom.nc;
27
28 import com.sun.xml.internal.rngom.ast.om.ParsedNameClass;
29
30 import javax.xml.namespace.QName;
31 import java.io.Serializable;
32 import java.util.HashSet;
33 import java.util.Set;
34
35 /**
36 * Name class is a set of {@link QName}s.
37 */
38 public abstract class NameClass implements ParsedNameClass, Serializable {
39 static final int SPECIFICITY_NONE = -1;
40 static final int SPECIFICITY_ANY_NAME = 0;
41 static final int SPECIFICITY_NS_NAME = 1;
42 static final int SPECIFICITY_NAME = 2;
43
44 /**
45 * Returns true if the given {@link QName} is a valid name
46 * for this QName.
47 */
48 public abstract boolean contains(QName name);
49
50 public abstract int containsSpecificity(QName name);
51
52 /**
53 * Visitor pattern support.
54 */
55 public abstract <V> V accept(NameClassVisitor<V> visitor);
56
57 /**
58 * Returns true if the name class accepts infinite number of
59 * {@link QName}s.
60 *
61 * <p>
62 * Intuitively, this method returns true if the name class is
63 * some sort of wildcard.
64 */
65 public abstract boolean isOpen();
66
67 /**
68 * If the name class is closed (IOW !{@link #isOpen()}),
69 * return the set of names in this name class. Otherwise the behavior
70 * is undefined.
71 */
72 public Set<QName> listNames() {
73 final Set<QName> names = new HashSet<QName>();
74 accept(new NameClassWalker() {
75 public Void visitName(QName name) {
76 names.add(name);
77 return null;
78 }
79 });
80 return names;
81 }
82
83 /**
84 * Returns true if the intersection between this name class
85 * and the specified name class is non-empty.
86 */
87 public final boolean hasOverlapWith( NameClass nc2 ) {
88 return OverlapDetector.overlap(this,nc2);
89 }
90
91
92 /** Sigleton instance that represents "anyName". */
93 public static final NameClass ANY = new AnyNameClass();
94
95 /**
96 * Sigleton instance that accepts no name.
97 *
98 * <p>
99 * This instance is useful when doing boolean arithmetic over
100 * name classes (such as computing an inverse of a given name class, etc),
101 * even though it can never appear in a RELAX NG surface syntax.
102 *
103 * <p>
104 * Internally, this instance is also used for:
105 * <ol>
106 * <li>Used to recover from errors during parsing.
107 * <li>Mark element patterns with <notAllowed/> content model.
108 * </ol>
109 */
110 public static final NameClass NULL = new NullNameClass();
111 }