Java example source code file (ParameterAnnotations.java)

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Java - Java tags/keywords

annotation, assertionerror, class, method, mypolicy, named, object, parameterannotations, permission, reflection, security, securitymanager, some, string, target, throwable

The ParameterAnnotations.java Java example source code

/*
 * Copyright (c) 2008, 2010, 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 6761678
 * @summary Check properties of Annotations returned from
 * getParameterAnnotations, including freedom from security
 * exceptions.
 * @run main/othervm ParameterAnnotations
 * @author Martin Buchholz
 */

import java.lang.annotation.Annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Method;
import java.security.Permission;
import java.security.Policy;
import java.security.ProtectionDomain;

@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.FIELD, ElementType.PARAMETER })
@interface Named {
  String value();
}

public class ParameterAnnotations {

    // A security policy that differs from the default only in that it
    // allows a security manager to be uninstalled.
    static class MyPolicy extends Policy {
        final Policy defaultPolicy;
        MyPolicy(Policy defaultPolicy) {
            this.defaultPolicy = defaultPolicy;
        }
        public boolean implies(ProtectionDomain pd, Permission p) {
            return p.getName().equals("setSecurityManager") ||
                defaultPolicy.implies(pd, p);
        }
    }

    public void nop(@Named("foo") Object foo,
                    @Named("bar") Object bar) {
    }

    void test(String[] args) throws Throwable {
        // Test without a security manager
        test1();

        // Test with a security manager
        Policy defaultPolicy = Policy.getPolicy();
        Policy.setPolicy(new MyPolicy(defaultPolicy));
        System.setSecurityManager(new SecurityManager());
        try {
            test1();
        } finally {
            System.setSecurityManager(null);
            Policy.setPolicy(defaultPolicy);
        }
    }

    void test1() throws Throwable {
        for (Method m : thisClass.getMethods()) {
            if (m.getName().equals("nop")) {
                Annotation[][] ann = m.getParameterAnnotations();
                equal(ann.length, 2);
                Annotation foo = ann[0][0];
                Annotation bar = ann[1][0];
                equal(foo.toString(), "@Named(value=foo)");
                equal(bar.toString(), "@Named(value=bar)");
                check(foo.equals(foo));
                check(! foo.equals(bar));
            }
        }
    }

    //--------------------- Infrastructure ---------------------------
    volatile int passed = 0, failed = 0;
    void pass() {passed++;}
    void fail() {failed++; Thread.dumpStack();}
    void fail(String msg) {System.err.println(msg); fail();}
    void unexpected(Throwable t) {failed++; t.printStackTrace();}
    void check(boolean cond) {if (cond) pass(); else fail();}
    void equal(Object x, Object y) {
        if (x == null ? y == null : x.equals(y)) pass();
        else fail(x + " not equal to " + y);}
    static Class<?> thisClass = new Object(){}.getClass().getEnclosingClass();
    public static void main(String[] args) throws Throwable {
        try {thisClass.getMethod("instanceMain",String[].class)
                .invoke(thisClass.newInstance(), (Object) args);}
        catch (Throwable e) {throw e.getCause();}}
    public void instanceMain(String[] args) throws Throwable {
        try {test(args);} catch (Throwable t) {unexpected(t);}
        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
        if (failed > 0) throw new AssertionError("Some tests failed");}
}