/*

 * Copyright (c) 1997, 2002, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

package sun.awt.image;

import java.awt.image.ImageConsumer;

class ImageConsumerQueue {

    ImageConsumerQueue next;

    ImageConsumer consumer;

    boolean interested;

    Object securityContext;

    boolean secure;

    static ImageConsumerQueue removeConsumer(ImageConsumerQueue cqbase,

                                             ImageConsumer ic,

                                             boolean stillinterested)

    {

        ImageConsumerQueue cqprev = null;

        for (ImageConsumerQueue cq = cqbase; cq != null; cq = cq.next) {

            if (cq.consumer == ic) {

                if (cqprev == null) {

                    cqbase = cq.next;

                } else {

                    cqprev.next = cq.next;

                }

                cq.interested = stillinterested;

                break;

            }

            cqprev = cq;

        }

        return cqbase;

    }

    static boolean isConsumer(ImageConsumerQueue cqbase, ImageConsumer ic) {

        for (ImageConsumerQueue cq = cqbase; cq != null; cq = cq.next) {

            if (cq.consumer == ic) {

                return true;

            }

        }

        return false;

    }

    ImageConsumerQueue(InputStreamImageSource src, ImageConsumer ic) {

        consumer = ic;

        interested = true;

        // ImageReps do their own security at access time.

        if (ic instanceof ImageRepresentation) {

            ImageRepresentation ir = (ImageRepresentation) ic;

            if (ir.image.source != src) {

                throw new SecurityException("ImageRep added to wrong image source");

            }

            secure = true;

        } else {

            SecurityManager security = System.getSecurityManager();

            if (security != null) {

                securityContext = security.getSecurityContext();

            } else {

                securityContext = null;

            }

        }

    }

    public String toString() {

        return ("[" + consumer +

                ", " + (interested ? "" : "not ") + "interested" +

                (securityContext != null ? ", " + securityContext : "") +

                "]");

    }

}