1 /*
2 * Copyright (c) 2017, 2026, 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 /*
26 * @test
27 * @summary test core reflection on value classes
28 * @enablePreview
29 * @run junit/othervm Reflection
30 */
31
32 import java.lang.reflect.Array;
33 import java.lang.reflect.Constructor;
34 import java.lang.reflect.Field;
35 import java.lang.reflect.InvocationTargetException;
36 import java.lang.reflect.Method;
37 import java.util.Arrays;
38 import java.util.stream.Stream;
39
40 import jdk.internal.value.ValueClass;
41 import jdk.internal.vm.annotation.LooselyConsistentValue;
42 import jdk.internal.vm.annotation.NullRestricted;
43 import org.junit.jupiter.api.Test;
44 import org.junit.jupiter.params.ParameterizedTest;
45 import org.junit.jupiter.params.provider.Arguments;
46 import org.junit.jupiter.params.provider.MethodSource;
47 import static org.junit.jupiter.api.Assertions.*;
48
49 public class Reflection {
50 @LooselyConsistentValue
51 static value class V {
52 int x;
53 V(int x) {
54 this.x = x;
55 }
56 }
57
58 @LooselyConsistentValue
59 static value class Value {
60 @NullRestricted
61 V v1;
62 V v2;
63 Value(V v1, V v2) {
64 this.v1 = v1;
65 this.v2 = v2;
66 }
67
68 static Value newValue(V v1, V v2) {
69 return new Value(v1, v2);
70 }
71 }
72
73 @Test
74 void testNewInstance() throws Exception {
75 V v = new V(10);
76 Constructor<Value> ctor = Value.class.getDeclaredConstructor(V.class, V.class);
77 Value o = ctor.newInstance(v, v);
78 assertEquals(o.getClass(), Value.class);
79 }
80
81 @Test
82 void testAccess() throws Exception {
83 Field field = Value.class.getDeclaredField("v1");
84 V v = new V(10);
85 Value o = new Value(v, null);
86 assertEquals(v, field.get(o));
87
88 // accessible but no write access
89 assertTrue(field.trySetAccessible());
90 assertTrue(field.isAccessible());
91 assertThrows(IllegalAccessException.class, () -> field.set(o, v));
92 }
93
94 @Test
95 void testNullRestricted() throws Exception {
96 Method m = Value.class.getDeclaredMethod("newValue", V.class, V.class);
97 Throwable t = assertThrows(InvocationTargetException.class, () -> m.invoke(null, new Object[] {null, null}));
98 assertEquals(NullPointerException.class, t.getCause().getClass());
99 }
100
101 static Stream<Arguments> arrays() {
102 V v1 = new V(10);
103 V v2 = new V(20);
104 Value value = new Value(v1, v2);
105
106 V[] varray = (V[]) Array.newInstance(V.class, 2);
107 V[] varrayNR = (V[]) ValueClass.newNullRestrictedAtomicArray(V.class, 3, new V(0));
108 Value[] valuearray = (Value[]) Array.newInstance(Value.class, 2);
109 Value[] valuearrayNR = (Value[]) ValueClass.newNullRestrictedNonAtomicArray(Value.class, 3, new Value(new V(0), new V(0)));
110
111 return Stream.of(
112 Arguments.of(V[].class, varray, false, v1),
113 Arguments.of(V[].class, varrayNR, true, v2),
114 Arguments.of(Value[].class, valuearray, false, value),
115 Arguments.of(Value[].class, valuearrayNR, true, value)
116
117 );
118 }
119
120 /**
121 * Setting the elements of an array.
122 * NPE will be thrown if null is set on an element in a null-restricted value class array
123 */
124 @ParameterizedTest
125 @MethodSource("arrays")
126 public void testArrays(Class<?> arrayClass, Object[] array, boolean nullRestricted, Object element) {
127 Class<?> componentType = arrayClass.getComponentType();
128 assertTrue(arrayClass.isArray());
129 // TODO: check Array.getComponentType(array) instead
130 assertTrue(array.getClass() == arrayClass || nullRestricted);
131 assertTrue(array.getClass().getComponentType() == componentType || nullRestricted);
132
133 for (int i = 0; i < array.length; i++) {
134 Object o = Array.get(array, i);
135 if (nullRestricted) {
136 assertTrue(o != null);
137 } else {
138 assertTrue(o == null);
139 }
140 }
141
142 // set elements
143 for (int i = 0; i < array.length; i++) {
144 Array.set(array, i, element);
145 assertTrue(Array.get(array, i) == element);
146 }
147
148 Arrays.setAll(array, i -> array[i]);
149
150 // test nullable
151 for (int i = 0; i < array.length; i++) {
152 if (nullRestricted) {
153 final int index = i;
154 assertThrows(NullPointerException.class, () -> Array.set(array, index, null));
155 } else {
156 Array.set(array, i, null);
157 }
158 }
159 }
160
161 @Test
162 @SuppressWarnings("removal")
163 public void testArraysWrongType() {
164 Integer[] array = {1, 2, 3};
165 assertThrows(IllegalArgumentException.class, () -> Array.set(array, 2, new Byte((byte) 5)));
166 }
167 }