1 /*
2 * Copyright (c) 1997, 2003, 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 sun.tools.util;
27
28 import sun.tools.java.*;
29
30
31 /**
32 * A class whose instances are filters over Modifier bits.
33 * Filtering is done by returning boolean values.
34 * Classes, methods and fields can be filtered, or filtering
35 * can be done directly on modifier bits.
36 *
37 * WARNING: The contents of this source file are not part of any
38 * supported API. Code that depends on them does so at its own risk:
39 * they are subject to change or removal without notice.
40 *
41 * @see java.lang.reflect.Modifier
42 * @author Robert Field
43 */
44
45 public
46 class ModifierFilter extends java.lang.reflect.Modifier {
47
48 /**
49 * Package private access.
50 * A "pseudo-" modifier bit that can be used in the
51 * constructors of this class to specify package private
52 * access. This is needed since there is no Modifier.PACKAGE.
53 */
54 public static final long PACKAGE = 0x8000000000000000L;
55
56 /**
57 * All access modifiers.
58 * A short-hand set of modifier bits that can be used in the
59 * constructors of this class to specify all access modifiers,
60 * Same as PRIVATE | PROTECTED | PUBLIC | PACKAGE.
61 */
62 public static final long ALL_ACCESS =
63 PRIVATE | PROTECTED | PUBLIC | PACKAGE;
64
65 private long oneOf;
66 private long must;
67 private long cannot;
68
69 private static final int ACCESS_BITS = PRIVATE | PROTECTED | PUBLIC;
70
71 /**
72 * Constructor - Specify a filter.
73 *
74 * @param oneOf If zero, everything passes the filter.
75 * If non-zero, at least one of the specified
76 * bits must be on in the modifier bits to
77 * pass the filter.
78 */
79 public
80 ModifierFilter(long oneOf) {
81 this(oneOf, 0, 0);
82 }
83
84 /**
85 * Constructor - Specify a filter.
86 * For example, the filter below will only pass synchronized
87 * methods that are private or package private access and are
88 * not native or static.
89 * <pre>
90 * ModifierFilter( Modifier.PRIVATE | ModifierFilter.PACKAGE,
91 * Modifier.SYNCHRONIZED,
92 * Modifier.NATIVE | Modifier.STATIC)
93 * </pre><p>
94 * Each of the three arguments must either be
95 * zero or the or'ed combination of the bits specified in the
96 * class Modifier or this class. During filtering, these values
97 * are compared against the modifier bits as follows:
98 *
99 * @param oneOf If zero, ignore this argument.
100 * If non-zero, at least one of the bits must be on.
101 * @param must All bits specified must be on.
102 * @param cannot None of the bits specified can be on.
103 */
104 public
105 ModifierFilter(long oneOf, long must, long cannot) {
106 this.oneOf = oneOf;
107 this.must = must;
108 this.cannot = cannot;
109 }
110
111 /**
112 * Filter on modifier bits.
113 *
114 * @param modifierBits Bits as specified in the Modifier class
115 *
116 * @return Whether the modifierBits pass this filter.
117 */
118 public boolean checkModifier(int modifierBits) {
119 // Add in the "pseudo-" modifier bit PACKAGE, if needed
120 long fmod = ((modifierBits & ACCESS_BITS) == 0) ?
121 modifierBits | PACKAGE :
122 modifierBits;
123 return ((oneOf == 0) || ((oneOf & fmod) != 0)) &&
124 ((must & fmod) == must) &&
125 ((cannot & fmod) == 0);
126 }
127
128 /**
129 * Filter a MemberDefinition.
130 *
131 * @param field A MemberDefinition
132 *
133 * @return Whether the modifier of the field
134 * passes this filter.
135 *
136 * @see sun.tools.MemberDefinition
137 */
138 public boolean checkMember(MemberDefinition field) {
139 return checkModifier(field.getModifiers());
140 }
141
142 /**
143 * Filter a ClassDefinition.
144 *
145 * @param cdef A ClassDefinition
146 *
147 * @return Whether the modifier of the class
148 * passes this filter.
149 *
150 * @see sun.tools.ClassDefinition
151 */
152 public boolean checkClass(ClassDefinition cdef) {
153 return checkModifier(cdef.getModifiers());
154 }
155
156 } // end ModifierFilter