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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2016 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.wildfly.security.permission;

import java.security.Permission;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.concurrent.atomic.AtomicReference;

import org.wildfly.security.util.ArrayIterator;

/**
 * A trivially simple permission collection, suitable as a default for most permission types (though probably not as efficient
 * as a specialized type in many cases).
 *
 * @author David M. Lloyd
 */
public final class SimplePermissionCollection extends AbstractPermissionCollection {

    private static final long serialVersionUID = - 9157630531211570679L;

    private final AtomicReference permissionsRef = new AtomicReference<>(PermissionUtil.NO_PERMISSIONS);

    /**
     * Construct a new instance.
     *
     * @param sourcePermission the source permission for this collection (must not be {@code null})
     */
    public SimplePermissionCollection(final AbstractPermission sourcePermission) {
        super(sourcePermission);
    }

    public int size() {
        return permissionsRef.get().length;
    }

    protected void doAdd(final AbstractPermission permission) {
        Permission[] oldVal, readVal, newVal;
        int count;
        final AtomicReference permissionsRef = this.permissionsRef;
        do {
            readVal = permissionsRef.get();
            do {
                count = 0;
                oldVal = readVal;
                for (Permission test : oldVal) {
                    if (test.implies(permission)) {
                        return;
                    }
                    if (! permission.implies(test)) {
                        // prepare to skip any permissions that are obviated by this one
                        count ++;
                    }
                }
                // see if it's still what we expect before we commit to the possibly expensive update...
                readVal = permissionsRef.get();
            } while (readVal != oldVal);
            newVal = new Permission[count + 1];
            int i = 0;
            for (Permission test : oldVal) {
                if (! permission.implies(test)) {
                    newVal[i++] = test;
                }
            }
            newVal[i] = permission;
        } while (! permissionsRef.compareAndSet(oldVal, newVal));
    }

    public boolean implies(final Permission permission) {
        for (Permission test : permissionsRef.get()) {
            if (test.implies(permission)) {
                return true;
            }
        }
        return false;
    }

    public Iterator iterator() {
        return new ArrayIterator(permissionsRef.get());
    }

    public Enumeration elements() {
        return new ArrayIterator(permissionsRef.get());
    }
}