Java example source code file (AnnotationsInheritanceOrderRedefinitionTest.java)

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Java - Java tags/keywords

ann1, ann2, ann3, annotation, class, inherited, object, reflection, runtimeexception, string, stringbuilder, stringjoiner, util

The AnnotationsInheritanceOrderRedefinitionTest.java Java example source code

/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 8011940
 * @summary Test inheritance, order and class redefinition behaviour of RUNTIME
 *          class annotations
 * @author plevart
 */

import sun.reflect.annotation.AnnotationParser;

import java.lang.annotation.Annotation;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.StringJoiner;

public class AnnotationsInheritanceOrderRedefinitionTest {

    @Retention(RetentionPolicy.RUNTIME)
    @Inherited
    @interface Ann1 {
        String value();
    }

    @Retention(RetentionPolicy.RUNTIME)
    @Inherited
    @interface Ann2 {
        String value();
    }

    @Retention(RetentionPolicy.RUNTIME)
    @Inherited
    @interface Ann3 {
        String value();
    }

    @Ann1("A")
    @Ann2("A")
    static class A {}

    @Ann3("B")
    static class B extends A {}

    @Ann1("C")
    @Ann3("C")
    static class C extends B {}

    public static void main(String[] args) {

        StringBuilder msgs = new StringBuilder();
        boolean ok = true;

        ok &= annotationsEqual(msgs, A.class, true,
            ann(Ann1.class, "A"), ann(Ann2.class, "A"));
        ok &= annotationsEqual(msgs, A.class, false,
            ann(Ann1.class, "A"), ann(Ann2.class, "A"));
        ok &= annotationsEqual(msgs, B.class, true,
            ann(Ann3.class, "B"));
        ok &= annotationsEqual(msgs, B.class, false,
            ann(Ann1.class, "A"), ann(Ann2.class, "A"), ann(Ann3.class, "B"));
        ok &= annotationsEqual(msgs, C.class, true,
            ann(Ann1.class, "C"), ann(Ann3.class, "C"));
        ok &= annotationsEqual(msgs, C.class, false,
            ann(Ann1.class, "C"), ann(Ann2.class, "A"), ann(Ann3.class, "C"));

        Annotation[] declaredAnnotatiosA = A.class.getDeclaredAnnotations();
        Annotation[] annotationsA = A.class.getAnnotations();
        Annotation[] declaredAnnotatiosB = B.class.getDeclaredAnnotations();
        Annotation[] annotationsB = B.class.getAnnotations();
        Annotation[] declaredAnnotatiosC = C.class.getDeclaredAnnotations();
        Annotation[] annotationsC = C.class.getAnnotations();

        incrementClassRedefinedCount(A.class);
        incrementClassRedefinedCount(B.class);
        incrementClassRedefinedCount(C.class);

        ok &= annotationsEqualButNotSame(msgs, A.class, true, declaredAnnotatiosA);
        ok &= annotationsEqualButNotSame(msgs, A.class, false, annotationsA);
        ok &= annotationsEqualButNotSame(msgs, B.class, true, declaredAnnotatiosB);
        ok &= annotationsEqualButNotSame(msgs, B.class, false, annotationsB);
        ok &= annotationsEqualButNotSame(msgs, C.class, true, declaredAnnotatiosC);
        ok &= annotationsEqualButNotSame(msgs, C.class, false, annotationsC);

        if (!ok) {
            throw new RuntimeException("test failure\n" + msgs);
        }
    }

    // utility methods

    private static boolean annotationsEqualButNotSame(StringBuilder msgs,
            Class<?> declaringClass, boolean declaredOnly, Annotation[] oldAnns) {
        if (!annotationsEqual(msgs, declaringClass, declaredOnly, oldAnns)) {
            return false;
        }
        Annotation[] anns = declaredOnly
                            ? declaringClass.getDeclaredAnnotations()
                            : declaringClass.getAnnotations();
        List<Annotation> sameAnns = new ArrayList<>();
        for (int i = 0; i < anns.length; i++) {
            if (anns[i] == oldAnns[i]) {
                sameAnns.add(anns[i]);
            }
        }
        if (!sameAnns.isEmpty()) {
            msgs.append(declaredOnly ? "declared " : "").append("annotations for ")
                .append(declaringClass.getSimpleName())
                .append(" not re-parsed after class redefinition: ")
                .append(toSimpleString(sameAnns)).append("\n");
            return false;
        } else {
            return true;
        }
    }

    private static boolean annotationsEqual(StringBuilder msgs,
            Class<?> declaringClass, boolean declaredOnly, Annotation... expectedAnns) {
        Annotation[] anns = declaredOnly
                            ? declaringClass.getDeclaredAnnotations()
                            : declaringClass.getAnnotations();
        if (!Arrays.equals(anns, expectedAnns)) {
            msgs.append(declaredOnly ? "declared " : "").append("annotations for ")
                .append(declaringClass.getSimpleName()).append(" are: ")
                .append(toSimpleString(anns)).append(", expected: ")
                .append(toSimpleString(expectedAnns)).append("\n");
            return false;
        } else {
            return true;
        }
    }

    private static Annotation ann(Class<? extends Annotation> annotationType,
                                  Object value) {
        return AnnotationParser.annotationForMap(annotationType,
            Collections.singletonMap("value", value));
    }

    private static String toSimpleString(List<Annotation> anns) {
        return toSimpleString(anns.toArray(new Annotation[anns.size()]));
    }

    private static String toSimpleString(Annotation[] anns) {
        StringJoiner joiner = new StringJoiner(", ");
        for (Annotation ann : anns) {
            joiner.add(toSimpleString(ann));
        }
        return joiner.toString();
    }

    private static String toSimpleString(Annotation ann) {
        Class<? extends Annotation> annotationType = ann.annotationType();
        Object value;
        try {
            value = annotationType.getDeclaredMethod("value").invoke(ann);
        } catch (IllegalAccessException | InvocationTargetException
            | NoSuchMethodException e) {
            throw new RuntimeException(e);
        }
        return "@" + annotationType.getSimpleName() + "(" + value + ")";
    }

    private static final Field classRedefinedCountField;

    static {
        try {
            classRedefinedCountField = Class.class.getDeclaredField("classRedefinedCount");
            classRedefinedCountField.setAccessible(true);
        } catch (NoSuchFieldException e) {
            throw new Error(e);
        }
    }

    private static void incrementClassRedefinedCount(Class<?> clazz) {
        try {
            classRedefinedCountField.set(clazz,
                ((Integer) classRedefinedCountField.get(clazz)) + 1);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}