author | bpb |
Fri, 05 Jan 2018 12:45:52 -0800 | |
changeset 48435 | 20fe8cd3179d |
parent 47216 | 71c04702a3d5 |
child 58242 | 94bb65cb37d3 |
permissions | -rw-r--r-- |
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/* |
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* Copyright (c) 1996, 2004, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.io; |
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import java.io.ObjectOutput; |
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import java.io.ObjectInput; |
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/** |
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* Only the identity of the class of an Externalizable instance is |
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* written in the serialization stream and it is the responsibility |
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* of the class to save and restore the contents of its instances. |
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* |
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* The writeExternal and readExternal methods of the Externalizable |
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* interface are implemented by a class to give the class complete |
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* control over the format and contents of the stream for an object |
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* and its supertypes. These methods must explicitly |
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* coordinate with the supertype to save its state. These methods supersede |
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* customized implementations of writeObject and readObject methods.<br> |
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* |
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* Object Serialization uses the Serializable and Externalizable |
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* interfaces. Object persistence mechanisms can use them as well. Each |
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* object to be stored is tested for the Externalizable interface. If |
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* the object supports Externalizable, the writeExternal method is called. If the |
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* object does not support Externalizable and does implement |
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* Serializable, the object is saved using |
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* ObjectOutputStream. <br> When an Externalizable object is |
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* reconstructed, an instance is created using the public no-arg |
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* constructor, then the readExternal method called. Serializable |
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* objects are restored by reading them from an ObjectInputStream.<br> |
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* |
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* An Externalizable instance can designate a substitution object via |
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* the writeReplace and readResolve methods documented in the Serializable |
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* interface.<br> |
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* |
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* @author unascribed |
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* @see java.io.ObjectOutputStream |
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* @see java.io.ObjectInputStream |
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* @see java.io.ObjectOutput |
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* @see java.io.ObjectInput |
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* @see java.io.Serializable |
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24865
09b1d992ca72
8044740: Convert all JDK versions used in @since tag to 1.n[.n] in jdk repo
henryjen
parents:
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diff
changeset
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* @since 1.1 |
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*/ |
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public interface Externalizable extends java.io.Serializable { |
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/** |
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* The object implements the writeExternal method to save its contents |
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* by calling the methods of DataOutput for its primitive values or |
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* calling the writeObject method of ObjectOutput for objects, strings, |
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* and arrays. |
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* |
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* @serialData Overriding methods should use this tag to describe |
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* the data layout of this Externalizable object. |
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* List the sequence of element types and, if possible, |
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* relate the element to a public/protected field and/or |
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* method of this Externalizable class. |
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* |
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* @param out the stream to write the object to |
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* @exception IOException Includes any I/O exceptions that may occur |
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*/ |
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void writeExternal(ObjectOutput out) throws IOException; |
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/** |
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* The object implements the readExternal method to restore its |
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* contents by calling the methods of DataInput for primitive |
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* types and readObject for objects, strings and arrays. The |
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* readExternal method must read the values in the same sequence |
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* and with the same types as were written by writeExternal. |
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* |
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* @param in the stream to read data from in order to restore the object |
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* @exception IOException if I/O errors occur |
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* @exception ClassNotFoundException If the class for an object being |
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* restored cannot be found. |
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*/ |
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void readExternal(ObjectInput in) throws IOException, ClassNotFoundException; |
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} |