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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @summary Test that isValue and modifiers return correct results for value classes & arrays
 * @library /test/lib
 * @enablePreview false
 * @modules java.base/jdk.internal.misc
 *          java.base/jdk.internal.value
 * @run junit/othervm IdentityReflectionTest
 * @run junit/othervm --enable-preview IdentityReflectionTest
 */

import org.junit.jupiter.api.Test;

import java.lang.classfile.ClassFile;
import java.lang.reflect.AccessFlag;
import java.lang.reflect.Modifier;
import java.util.Set;

import jdk.internal.misc.PreviewFeatures;

import static jdk.test.lib.Asserts.*;

public class IdentityReflectionTest {

    static final boolean PREVIEW = PreviewFeatures.isEnabled();

    static final Class<?>[] valueClasses = {
        Number.class,
        Record.class,

        Byte.class,
        Short.class,
        Integer.class,
        Long.class,
        Float.class,
        Double.class,
        Boolean.class,
        Character.class,

        java.util.Optional.class,
        java.util.OptionalDouble.class,
        java.util.OptionalInt.class,
        java.util.OptionalLong.class,

        java.time.Duration.class,
        java.time.Instant.class,
        java.time.LocalDate.class,
        java.time.LocalDateTime.class,
        java.time.LocalTime.class,
        java.time.MonthDay.class,
        java.time.OffsetDateTime.class,
        java.time.OffsetTime.class,
        java.time.Period.class,
        java.time.Year.class,
        java.time.YearMonth.class,
        java.time.ZonedDateTime.class,

        java.time.chrono.HijrahDate.class,
        java.time.chrono.JapaneseDate.class,
        java.time.chrono.MinguoDate.class,
        java.time.chrono.ThaiBuddhistDate.class,
    };

    static final Class<?>[] identityClasses = {
        Object.class,
        String.class,
        Thread.class,
        java.math.BigInteger.class,
        java.math.BigDecimal.class,
        Integer[].class,
        Thread[].class,
    };

    @Test
    void testIsValue() {
        checkIsValue(int.class, false);
        checkIsValue(Runnable.class, false);
        for (Class<?> c : valueClasses) {
            checkIsValue(c, PREVIEW);
        }
        for (Class<?> c : identityClasses) {
            checkIsValue(c, false);
        }
    }

    @SuppressWarnings("preview")
    void checkIsValue(Class<?> c, boolean expected) {
        assertEquals(expected, c.isValue(),
                      c + " " + (expected ? "is" : "is not") + " a value class");
    }

    @Test
    void testModifiers() {
        checkIdentityModifier(int.class, false);
        checkIdentityModifier(Runnable.class, false);
        for (Class<?> c : valueClasses) {
            checkIdentityModifier(c, false);
        }
        for (Class<?> c : identityClasses) {
            checkIdentityModifier(c, PREVIEW);
        }
    }

    @SuppressWarnings("preview")
    void checkIdentityModifier(Class<?> c, boolean expected) {
        int mod = c.getModifiers();
        assertEquals(expected, (mod & ClassFile.ACC_IDENTITY) != 0,
            "Modifier of " + c + " (" + Integer.toHexString(mod) + ") " +
            (expected ? "should" : "should not") + " have ACC_IDENTITY set");
    }

    @Test
    void testAccessFlags() {
        checkIdentityAccessFlag(int.class, false);
        checkIdentityAccessFlag(Runnable.class, false);
        for (Class<?> c : valueClasses) {
            checkIdentityAccessFlag(c, false);
        }
        for (Class<?> c : identityClasses) {
            checkIdentityAccessFlag(c, PREVIEW);
        }
    }

    @SuppressWarnings("preview")
    void checkIdentityAccessFlag(Class<?> c, boolean expected) {
        Set<AccessFlag> acc = c.accessFlags();
        assertEquals(expected, acc.contains(AccessFlag.IDENTITY),
            "Access flags of " + c + " (" + acc + ") " +
            (expected ? "should" : "should not") + " contain IDENTITY");
    }
}