test/hotspot/jtreg/runtime/sealedClasses/GetPermittedSubclassesTest.java

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/*
 * @test
 * @bug 8225056
 * @compile GetPermittedSubclasses.jcod
 * @compile noSubclass/BaseC.java noSubclass/BaseI.java noSubclass/Impl1.java
 * @compile noSubclass/Impl2.java
 * @run main GetPermittedSubclassesTest
 */

import java.util.ArrayList;

// Test Class GetPermittedSubtpes() and Class.isSealed() APIs.
public class GetPermittedSubclassesTest {

    sealed class Sealed1 permits Sub1 {}

    final class Sub1 extends Sealed1 implements SealedI1 {}

    sealed interface SealedI1 permits NotSealed, Sub1, Extender {}

    non-sealed interface Extender extends SealedI1 { }

    final class FinalC implements Extender {}

    final class NotSealed implements SealedI1 {}

    final class Final4 {}

    public static void testSealedInfo(Class<?> c, String[] expected, boolean isSealed) {
        var permitted = c.getPermittedSubclasses();

        if (isSealed) {
            if (permitted.length != expected.length) {
                throw new RuntimeException(
                    "Unexpected number of permitted subclasses for: " + c.toString() +
                    "(" + java.util.Arrays.asList(permitted));
            }

            if (!c.isSealed()) {
                throw new RuntimeException("Expected sealed class: " + c.toString());
            }

            // Create ArrayList of permitted subclasses class names.
            ArrayList<String> permittedNames = new ArrayList<String>();
            for (int i = 0; i < permitted.length; i++) {
                permittedNames.add(permitted[i].getName());
            }

            if (permittedNames.size() != expected.length) {
                throw new RuntimeException(
                    "Unexpected number of permitted names for: " + c.toString());
            }

            // Check that expected class names are in the permitted subclasses list.
            for (int i = 0; i < expected.length; i++) {
                if (!permittedNames.contains(expected[i])) {
                    throw new RuntimeException(
                         "Expected class not found in permitted subclases list, super class: " +
                         c.getName() + ", expected class: " + expected[i]);
                }
            }
        } else {
            // Must not be sealed.
            if (c.isSealed() || permitted != null) {
                throw new RuntimeException("Unexpected sealed class: " + c.toString());
            }
        }
    }

    public static void testBadSealedClass(String className,
                                          Class<?> expectedException,
                                          String expectedCFEMessage) throws Throwable {
        try {
            Class.forName(className);
            throw new RuntimeException("Expected ClassFormatError exception not thrown for " + className);
        } catch (ClassFormatError cfe) {
            if (ClassFormatError.class != expectedException) {
                throw new RuntimeException(
                    "Class " + className + " got unexpected exception: " + cfe.getMessage());
            }
            if (!cfe.getMessage().contains(expectedCFEMessage)) {
                throw new RuntimeException(
                    "Class " + className + " got unexpected ClassFormatError exception: " + cfe.getMessage());
            }
        } catch (IncompatibleClassChangeError icce) {
            if (IncompatibleClassChangeError.class != expectedException) {
                throw new RuntimeException(
                    "Class " + className + " got unexpected exception: " + icce.getMessage());
            }
            if (!icce.getMessage().contains(expectedCFEMessage)) {
                throw new RuntimeException(
                    "Class " + className + " got unexpected IncompatibleClassChangeError exception: " + icce.getMessage());
            }
        }
    }

    public static void main(String... args) throws Throwable {
        testSealedInfo(SealedI1.class, new String[] {"GetPermittedSubclassesTest$NotSealed",
                                                     "GetPermittedSubclassesTest$Sub1",
                                                     "GetPermittedSubclassesTest$Extender"},
                                                     true);

        testSealedInfo(Sealed1.class, new String[] {"GetPermittedSubclassesTest$Sub1"}, true);
        testSealedInfo(Final4.class, null, false);
        testSealedInfo(NotSealed.class, null, false);

        // Test class with PermittedSubclasses attribute but old class file version.
        testSealedInfo(OldClassFile.class, null, false);

        // Test class with an empty PermittedSubclasses attribute.
        testSealedInfo(NoSubclasses.class, new String[]{}, true);

        // Test that a class with an empty PermittedSubclasses attribute cannot be subclass-ed.
        testBadSealedClass("SubClass", IncompatibleClassChangeError.class,
                           "SubClass cannot inherit from sealed class NoSubclasses");

        // Test returning only names of existing classes.
        testSealedInfo(NoLoadSubclasses.class, new String[]{"ExistingClassFile" }, true);

        // Test that loading a class with a corrupted PermittedSubclasses attribute
        // causes a ClassFormatError.
        testBadSealedClass("BadPermittedAttr", ClassFormatError.class,
                           "Permitted subclass class_info_index 15 has bad constant type");

        // Test that loading a sealed final class with a PermittedSubclasses
        // attribute causes a ClassFormatError.
        testBadSealedClass("SealedButFinal", ClassFormatError.class,
                           "PermittedSubclasses attribute in final class");

        // Test that loading a sealed class with an ill-formed class name in its
        // PermittedSubclasses attribute causes a ClassFormatError.
        testBadSealedClass("BadPermittedSubclassEntry", ClassFormatError.class,
                           "Illegal class name \"iDont;;Exist\" in class file");

        // Test that loading a sealed class with an empty class name in its PermittedSubclasses
        // attribute causes a ClassFormatError.
        testBadSealedClass("EmptyPermittedSubclassEntry", ClassFormatError.class,
                           "Illegal class name \"\" in class file");

        //test type enumerated in the PermittedSubclasses attribute,
        //which are not direct subtypes of the current class are not returned:
        testSealedInfo(noSubclass.BaseC.class, new String[] {"noSubclass.ImplCIntermediate"}, true);
        testSealedInfo(noSubclass.BaseI.class, new String[] {"noSubclass.ImplIIntermediateI", "noSubclass.ImplIIntermediateC"}, true);
    }
}