1 /*

     2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

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

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

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package com.sun.xml.internal.bind;

    27 

    28 import javax.xml.bind.Marshaller;

    29 

    30 /**

    31  * Optional interface that can be implemented by JAXB-bound objects

    32  * to handle cycles in the object graph.

    33  *

    34  * <p>

    35  * As discussed in <a href="https://jaxb.dev.java.net/guide/Mapping_cyclic_references_to_XML.html">

    36  * the users' guide</a>, normally a cycle in the object graph causes the marshaller to report an error,

    37  * and when an error is found, the JAXB RI recovers by cutting the cycle arbitrarily.

    38  * This is not always a desired behavior.

    39  *

    40  * <p>

    41  * Implementing this interface allows user application to change this behavior.

    42  * Also see <a href="http://forums.java.net/jive/thread.jspa?threadID=13670">this related discussion</a>.

    43  *

    44  * @since JAXB 2.1 EA2

    45  * @author Kohsuke Kawaguchi

    46  */

    47 public interface CycleRecoverable {

    48     /**

    49      * Called when a cycle is detected by the JAXB RI marshaller

    50      * to nominate a new object to be marshalled instead.

    51      *

    52      * @param context

    53      *      This object is provided by the JAXB RI to inform

    54      *      the object about the marshalling process that's going on.

    55      *

    56      *

    57      * @return

    58      *      the object to be marshalled instead of <tt>this</tt> object.

    59      *      Or return null to indicate that the JAXB RI should behave

    60      *      just like when your object does not implement {@link CycleRecoverable}

    61      *      (IOW, cut the cycle arbitrarily and try to go on.)

    62      */

    63     Object onCycleDetected(Context context);

    64 

    65     /**

    66      * This interface is implemented by the JAXB RI to provide

    67      * information about the on-going marshalling process.

    68      *

    69      * <p>

    70      * We may add more methods in the future, so please do not

    71      * implement this interface in your application.

    72      */

    73     public interface Context {

    74         /**

    75          * Returns the marshaller object that's doing the marshalling.

    76          *

    77          * @return

    78          *      always non-null.

    79          */

    80         Marshaller getMarshaller();

    81     }

    82 }