1 /*
  2  * Copyright (c) 2022, 2025, 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.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  */
 23 
 24 /*
 25  * @test id=Basic
 26  * @bug 8266670 8281463 8293626 8297271
 27  * @summary Basic tests of AccessFlag
 28  * @modules java.base/jdk.internal.misc
 29  * @run junit BasicAccessFlagTest
 30  */
 31 
 32 /*
 33  * @test id=BasicPreview
 34  * @bug 8266670 8281463 8293626 8297271
 35  * @summary Basic tests of AccessFlag
 36  * @modules java.base/jdk.internal.misc
 37  * @enablePreview
 38  * @run junit BasicAccessFlagTest
 39  */
 40 
 41 import java.lang.classfile.ClassFile;
 42 import java.lang.reflect.AccessFlag;
 43 import java.lang.reflect.ClassFileFormatVersion;
 44 import java.lang.reflect.Field;
 45 import java.lang.reflect.Modifier;
 46 import java.util.EnumSet;
 47 import java.util.Map;
 48 import java.util.LinkedHashMap;
 49 import java.util.HashSet;
 50 import java.util.Set;
 51 
 52 import jdk.internal.misc.PreviewFeatures;
 53 
 54 
 55 import org.junit.Test;
 56 import org.junit.jupiter.api.Assertions;
 57 
 58 import static org.junit.jupiter.api.Assertions.*;
 59 
 60 public class BasicAccessFlagTest {
 61 
 62     /*
 63      * Verify sourceModifier() == true access flags have a
 64      * corresponding constant in java.lang.reflect.Modifier.
 65      */
 66     @Test
 67     public void testSourceModifiers() throws Exception {
 68         Class<?> modifierClass = Modifier.class;
 69 
 70         for(AccessFlag accessFlag : AccessFlag.values()) {
 71             if (accessFlag.sourceModifier()) {
 72                 // Check for consistency
 73                 Field f = modifierClass.getField(accessFlag.name());
 74                 assertEquals(f.getInt(null), accessFlag.mask(), accessFlag + " mask");
 75             }
 76         }
 77     }
 78 
 79     // The mask values of the enum constants must be non-decreasing;
 80     // in other words stay the same (for colliding mask values) or go
 81     // up.
 82     @Test
 83     public void testMaskOrdering() {
 84         AccessFlag[] values = AccessFlag.values();
 85         for (int i = 1; i < values.length; i++) {
 86             AccessFlag left  = values[i-1];
 87             AccessFlag right = values[i];
 88             assertTrue(left.mask() <= right.mask(), () -> left
 89                     + "has a greater mask than "
 90                     + right);
 91         }
 92     }
 93 
 94     // Test that if access flags have a matching mask, their locations
 95     // are disjoint.
 96     @Test
 97     public void testDisjoint() {
 98         // First build the mask -> access flags map...
 99         Map<Integer, Set<AccessFlag>> maskToFlags = new LinkedHashMap<>();
100 
101         for (var accessFlag : AccessFlag.values()) {
102             Integer mask = accessFlag.mask();
103             Set<AccessFlag> flags = maskToFlags.get(mask);
104 
105             if (flags == null) {
106                 flags = new HashSet<>();
107                 flags.add(accessFlag);
108                 maskToFlags.put(mask, flags);
109             } else {
110                 flags.add(accessFlag);
111             }
112         }
113 
114         // ...then test for disjointness
115         for (var entry : maskToFlags.entrySet()) {
116             var value = entry.getValue();
117             if (value.size() == 0) {
118                 throw new AssertionError("Bad flag set " + entry);
119             } else if (value.size() == 1) {
120                 // Need at least two flags to be non-disjointness to
121                 // be possible
122                 continue;
123             }
124 
125             Set<AccessFlag.Location> locations = new HashSet<>();
126             for (var accessFlag : value) {
127                 if (accessFlag.equals(AccessFlag.SUPER))
128                     continue;       // SUPER is defined to overlap with IDENTITY
129                 for (var location : accessFlag.locations()) {
130                     boolean added = locations.add(location);
131                     if (!added) {
132                         reportError(location, accessFlag,
133                                     entry.getKey(), value);
134                     }
135                 }
136             }
137         }
138     }
139 
140     private static void reportError(AccessFlag.Location location,
141                                     AccessFlag accessFlag,
142                                     Integer mask, Set<AccessFlag> value) {
143         System.err.println("Location " + location +
144                            " from " + accessFlag +
145                            " already present for 0x" +
146                            Integer.toHexString(mask) + ": " + value);
147         throw new RuntimeException();
148     }
149 
150     // For each access flag, make sure it is recognized on every kind
151     // of location it can apply to
152     @Test
153     public void testMaskToAccessFlagsPositive() {
154         for (var accessFlag : AccessFlag.values()) {
155             Set<AccessFlag> expectedSet = EnumSet.of(accessFlag);
156             for (var location : accessFlag.locations()) {
157                 Set<AccessFlag> computedSet =
158                     AccessFlag.maskToAccessFlags(accessFlag.mask(), location);
159                 if (!computedSet.containsAll(expectedSet)) {
160                     System.out.println("expected: " + expectedSet);
161                     System.out.println("computed: " + computedSet);
162                     throw new RuntimeException("Bad set computation on " +
163                                                accessFlag + ", " + location);
164                 }
165             }
166             for (var cffv : ClassFileFormatVersion.values()) {
167                 for (var location : accessFlag.locations(cffv)) {
168                     Set<AccessFlag> computedSet =
169                             AccessFlag.maskToAccessFlags(accessFlag.mask(), location, cffv);
170                     if (!expectedSet.equals(computedSet)) {
171                         throw new RuntimeException("Bad set computation on " +
172                                 accessFlag + ", " + location);
173                     }
174                 }
175             }
176         }
177         assertEquals(Set.of(AccessFlag.STRICT), AccessFlag.maskToAccessFlags(Modifier.STRICT, AccessFlag.Location.METHOD, ClassFileFormatVersion.RELEASE_8));
178     }
179 
180     @Test
181     public void testMaskToAccessFlagsNegative() {
182         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(Modifier.STRICT, AccessFlag.Location.METHOD));
183         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(Modifier.STRICT, AccessFlag.Location.METHOD, ClassFileFormatVersion.RELEASE_17));
184         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(Modifier.STRICT, AccessFlag.Location.METHOD, ClassFileFormatVersion.RELEASE_1));
185         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(Modifier.PRIVATE, AccessFlag.Location.CLASS));
186         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_MODULE, AccessFlag.Location.CLASS, ClassFileFormatVersion.RELEASE_8));
187         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_ANNOTATION, AccessFlag.Location.CLASS, ClassFileFormatVersion.RELEASE_4));
188         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_ENUM, AccessFlag.Location.FIELD, ClassFileFormatVersion.RELEASE_4));
189         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_SYNTHETIC, AccessFlag.Location.INNER_CLASS, ClassFileFormatVersion.RELEASE_4));
190         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_PUBLIC, AccessFlag.Location.INNER_CLASS, ClassFileFormatVersion.RELEASE_0));
191         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_MANDATED, AccessFlag.Location.METHOD_PARAMETER, ClassFileFormatVersion.RELEASE_7));
192         assertThrows(IllegalArgumentException.class, () -> AccessFlag.maskToAccessFlags(ClassFile.ACC_MANDATED, AccessFlag.Location.MODULE, ClassFileFormatVersion.RELEASE_7));
193     }
194 
195     @Test
196     public void testLocationsNullHandling() {
197         for (var flag : AccessFlag.values()) {
198             assertThrows(NullPointerException.class, () -> flag.locations(null));
199         }
200 
201         for (var location : AccessFlag.Location.values()) {
202             assertThrows(NullPointerException.class, () -> location.flags(null));
203         }
204 
205         for (var location : AccessFlag.Location.values()) {
206             try {
207                 location.flags(null);
208                 throw new RuntimeException("Did not get NPE on " + location + ".flags(null)");
209             } catch (NullPointerException npe ) {
210                 ; // Expected
211             }
212             try {
213                 location.flagsMask(null);
214                 throw new RuntimeException("Did not get NPE on " + location + ".flagsMask(null)");
215             } catch (NullPointerException npe ) {
216                 ; // Expected
217             }
218         }
219     }
220 }