1 /* 2 * Copyright (c) 1997, 2012, 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 {@code this} 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 }