1 /*

     2  * Copyright 2003-2006 Sun Microsystems, Inc.  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.  Sun designates this

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

     9  * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package javax.sql.rowset.serial;

    27 

    28 import java.sql.*;

    29 import java.io.*;

    30 import java.util.Map;

    31 import java.lang.reflect.*;

    32 import javax.sql.rowset.RowSetWarning;

    33 

    34 /**

    35  * A serializable mapping in the Java programming language of an SQL

    36  * <code>JAVA_OBJECT</code> value. Assuming the Java object

    37  * implements the <code>Serializable</code> interface, this class simply wraps the

    38  * serialization process.

    39  * <P>

    40  * If however, the serialization is not possible because

    41  * the Java object is not immediately serializable, this class will

    42  * attempt to serialize all non-static members to permit the object

    43  * state to be serialized.

    44  * Static or transient fields cannot be serialized; an attempt to serialize

    45  * them will result in a <code>SerialException</code> object being thrown.

    46  *

    47  * @author Jonathan Bruce

    48  */

    49 public class SerialJavaObject implements Serializable, Cloneable {

    50 

    51     /**

    52      * Placeholder for object to be serialized.

    53      */

    54     private Object obj;

    55 

    56 

    57    /**

    58     * Placeholder for all fields in the <code>JavaObject</code> being serialized.

    59     */

    60     private transient Field[] fields;

    61 

    62     /**

    63      * Constructor for <code>SerialJavaObject</code> helper class.

    64      * <p>

    65      *

    66      * @param obj the Java <code>Object</code> to be serialized

    67      * @throws SerialException if the object is found

    68      * to be unserializable

    69      */

    70     public SerialJavaObject(Object obj) throws SerialException {

    71 

    72         // if any static fields are found, an exception

    73         // should be thrown

    74 

    75 

    76         // get Class. Object instance should always be available

    77         Class c = obj.getClass();

    78 

    79         // determine if object implements Serializable i/f

    80         boolean serializableImpl = false;

    81         Class[] theIf = c.getInterfaces();

    82         for (int i = 0; i < theIf.length; i++) {

    83             String ifName = theIf[i].getName();

    84             if (ifName == "java.io.Serializable") {

    85                 serializableImpl = true;

    86             }

    87         }

    88 

    89         // can only determine public fields (obviously). If

    90         // any of these are static, this should invalidate

    91         // the action of attempting to persist these fields

    92         // in a serialized form

    93 

    94         boolean anyStaticFields = false;

    95         fields = c.getFields();

    96         //fields = new Object[field.length];

    97 

    98         for (int i = 0; i < fields.length; i++ ) {

    99             if ( fields[i].getModifiers() == Modifier.STATIC ) {

   100                 anyStaticFields = true;

   101             }

   102             //fields[i] = field[i].get(obj);

   103         }

   104         try {

   105             if (!(serializableImpl)) {

   106                throw new RowSetWarning("Test");

   107             }

   108         } catch (RowSetWarning w) {

   109             setWarning(w);

   110         }

   111 

   112         if (anyStaticFields) {

   113             throw new SerialException("Located static fields in " +

   114                 "object instance. Cannot serialize");

   115         }

   116 

   117         this.obj = obj;

   118     }

   119 

   120     /**

   121      * Returns an <code>Object</code> that is a copy of this <code>SerialJavaObject</code>

   122      * object.

   123      *

   124      * @return a copy of this <code>SerialJavaObject</code> object as an

   125      *         <code>Object</code> in the Java programming language

   126      * @throws SerialException if the instance is corrupt

   127      */

   128     public Object getObject() throws SerialException {

   129         return this.obj;

   130     }

   131 

   132     /**

   133      * Returns an array of <code>Field</code> objects that contains each

   134      * field of the object that this helper class is serializing.

   135      *

   136      * @return an array of <code>Field</code> objects

   137      * @throws SerialException if an error is encountered accessing

   138      * the serialized object

   139      */

   140     public Field[] getFields() throws SerialException {

   141         if (fields != null) {

   142             Class c = this.obj.getClass();

   143             //the following has to be commented before mustang integration

   144             //return c.getFields();

   145             //the following has to be uncommented before mustang integration

   146             return sun.reflect.misc.FieldUtil.getFields(c);

   147         } else {

   148             throw new SerialException("SerialJavaObject does not contain" +

   149                 " a serialized object instance");

   150         }

   151     }

   152 

   153     /**

   154          * The identifier that assists in the serialization of this

   155      * <code>SerialJavaObject</code> object.

   156      */

   157     static final long serialVersionUID = -1465795139032831023L;

   158 

   159     /**

   160      * A container for the warnings issued on this <code>SerialJavaObject</code>

   161      * object. When there are multiple warnings, each warning is chained to the

   162      * previous warning.

   163      */

   164     java.util.Vector chain;

   165 

   166     /**

   167      * Registers the given warning.

   168      */

   169     private void setWarning(RowSetWarning e) {

   170         if (chain == null) {

   171             chain = new java.util.Vector();

   172         }

   173         chain.add(e);

   174     }

   175 }