1 /*
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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
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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
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23 
24 /**
25  * @test
26  * @build Fields HiddenClassTest
27  * @run testng/othervm HiddenClassTest
28  * @summary Test java.lang.reflect.AccessibleObject with modules
29  */
30 
31 import java.io.IOException;
32 import java.io.UncheckedIOException;
33 import java.lang.invoke.MethodHandles;
34 import java.lang.reflect.Field;
35 import java.lang.reflect.Modifier;
36 import java.nio.file.Files;
37 import java.nio.file.Path;
38 import java.nio.file.Paths;
39 
40 import org.testng.annotations.Test;
41 import static org.testng.Assert.*;
42 
43 public class HiddenClassTest {
44     static final Class<?> hiddenClass = defineHiddenClass();
defineHiddenClass()45     private static Class<?> defineHiddenClass() {
46         String classes = System.getProperty("test.classes");
47         Path cf = Paths.get(classes, "Fields.class");
48         try {
49             byte[] bytes = Files.readAllBytes(cf);
50             return MethodHandles.lookup().defineHiddenClass(bytes, true).lookupClass();
51         } catch (IOException e) {
52             throw new UncheckedIOException(e);
53         } catch (IllegalAccessException e) {
54             throw new RuntimeException(e);
55         }
56     }
57 
58     /*
59      * Test Field::set that can write the value of a non-static final field
60      * in a normal class
61      */
62     @Test
testFieldsInNormalClass()63     public void testFieldsInNormalClass() throws Throwable {
64         // despite the name "HiddenClass", this class is loaded by the
65         // class loader as non-hidden class
66         Class<?> c = Fields.class;
67         Fields o = new Fields();
68         assertFalse(c.isHidden());
69         readOnlyAccessibleObject(c, "STATIC_FINAL", null, true);
70         readWriteAccessibleObject(c, "STATIC_NON_FINAL", null, false);
71         readWriteAccessibleObject(c, "FINAL", o, true);
72         readWriteAccessibleObject(c, "NON_FINAL", o, false);
73     }
74 
75     /*
76      * Test Field::set that fails to write the value of a non-static final field
77      * in a hidden class
78      */
79     @Test
testFieldsInHiddenClass()80     public void testFieldsInHiddenClass() throws Throwable {
81         assertTrue(hiddenClass.isHidden());
82         Object o = hiddenClass.newInstance();
83         readOnlyAccessibleObject(hiddenClass, "STATIC_FINAL", null, true);
84         readWriteAccessibleObject(hiddenClass, "STATIC_NON_FINAL", null, false);
85         readOnlyAccessibleObject(hiddenClass, "FINAL", o, true);
86         readWriteAccessibleObject(hiddenClass, "NON_FINAL", o, false);
87     }
88 
readOnlyAccessibleObject(Class<?> c, String name, Object o, boolean isFinal)89     private static void readOnlyAccessibleObject(Class<?> c, String name, Object o, boolean isFinal) throws Exception {
90         Field f = c.getDeclaredField(name);
91         int modifier = f.getModifiers();
92         if (isFinal) {
93             assertTrue(Modifier.isFinal(modifier));
94         } else {
95             assertFalse(Modifier.isFinal(modifier));
96         }
97         assertTrue(f.trySetAccessible());
98         assertTrue(f.get(o) != null);
99         try {
100             f.set(o, null);
101             assertTrue(false, "should fail to set " + name);
102         } catch (IllegalAccessException e) {
103         }
104     }
105 
readWriteAccessibleObject(Class<?> c, String name, Object o, boolean isFinal)106     private static void readWriteAccessibleObject(Class<?> c, String name, Object o, boolean isFinal) throws Exception {
107         Field f = c.getDeclaredField(name);
108         int modifier = f.getModifiers();
109         if (isFinal) {
110             assertTrue(Modifier.isFinal(modifier));
111         } else {
112             assertFalse(Modifier.isFinal(modifier));
113         }
114         assertTrue(f.trySetAccessible());
115         assertTrue(f.get(o) != null);
116         try {
117             f.set(o, null);
118         } catch (IllegalAccessException e) {
119             throw e;
120         }
121     }
122 }
123