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	/*
	* Copyright (c) 2003, 2020, 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 javax.sql.rowset.serial;

	import java.sql.*;
	import java.io.*;
	import java.util.Map;
	import java.net.URL;
	import java.util.Arrays;


	/**
	* A serialized version of an <code>Array</code>
	* object, which is the mapping in the Java programming language of an SQL
	* <code>ARRAY</code> value.
	* <P>
	* The <code>SerialArray</code> class provides a constructor for creating
	* a <code>SerialArray</code> instance from an <code>Array</code> object,
	* methods for getting the base type and the SQL name for the base type, and
	* methods for copying all or part of a <code>SerialArray</code> object.
	* <P>
	*
	* Note: In order for this class to function correctly, a connection to the
	* data source
	* must be available in order for the SQL <code>Array</code> object to be
	* materialized (have all of its elements brought to the client server)
	* if necessary. At this time, logical pointers to the data in the data source,
	* such as locators, are not currently supported.
	*
	* <h2> Thread safety </h2>
	*
	* A SerialArray is not safe for use by multiple concurrent threads. If a
	* SerialArray is to be used by more than one thread then access to the
	* SerialArray should be controlled by appropriate synchronization.
	*
	* @since 1.5
	*/
	public class SerialArray implements Array, Serializable, Cloneable {

	/**
	* A serialized array in which each element is an <code>Object</code>
	* in the Java programming language that represents an element
	* in the SQL <code>ARRAY</code> value.
	* @serial
	*/
	@SuppressWarnings("serial") // Not statically typed as Serializable
	private Object[] elements;

	/**
	* The SQL type of the elements in this <code>SerialArray</code> object. The
	* type is expressed as one of the constants from the class
	* <code>java.sql.Types</code>.
	* @serial
	*/
	private int baseType;

	/**
	* The type name used by the DBMS for the elements in the SQL <code>ARRAY</code>
	* value that this <code>SerialArray</code> object represents.
	* @serial
	*/
	private String baseTypeName;

	/**
	* The number of elements in this <code>SerialArray</code> object, which
	* is also the number of elements in the SQL <code>ARRAY</code> value
	* that this <code>SerialArray</code> object represents.
	* @serial
	*/
	private int len;

	/**
	* Constructs a new <code>SerialArray</code> object from the given
	* <code>Array</code> object, using the given type map for the custom
	* mapping of each element when the elements are SQL UDTs.
	* <P>
	* This method does custom mapping if the array elements are a UDT
	* and the given type map has an entry for that UDT.
	* Custom mapping is recursive,
	* meaning that if, for instance, an element of an SQL structured type
	* is an SQL structured type that itself has an element that is an SQL
	* structured type, each structured type that has a custom mapping will be
	* mapped according to the given type map.
	* <P>
	* The new <code>SerialArray</code>
	* object contains the same elements as the <code>Array</code> object
	* from which it is built, except when the base type is the SQL type
	* <code>STRUCT</code>, <code>ARRAY</code>, <code>BLOB</code>,
	* <code>CLOB</code>, <code>DATALINK</code> or <code>JAVA_OBJECT</code>.
	* In this case, each element in the new
	* <code>SerialArray</code> object is the appropriate serialized form,
	* that is, a <code>SerialStruct</code>, <code>SerialArray</code>,
	* <code>SerialBlob</code>, <code>SerialClob</code>,
	* <code>SerialDatalink</code>, or <code>SerialJavaObject</code> object.
	* <P>
	* Note: (1) The <code>Array</code> object from which a <code>SerialArray</code>
	* object is created must have materialized the SQL <code>ARRAY</code> value's
	* data on the client before it is passed to the constructor. Otherwise,
	* the new <code>SerialArray</code> object will contain no data.
	* <p>
	* Note: (2) If the <code>Array</code> contains <code>java.sql.Types.JAVA_OBJECT</code>
	* types, the <code>SerialJavaObject</code> constructor is called where checks
	* are made to ensure this object is serializable.
	* <p>
	* Note: (3) The <code>Array</code> object supplied to this constructor cannot
	* return <code>null</code> for any <code>Array.getArray()</code> methods.
	* <code>SerialArray</code> cannot serialize null array values.
	*
	*
	* @param array the <code>Array</code> object to be serialized
	* @param map a <code>java.util.Map</code> object in which
	* each entry consists of 1) a <code>String</code> object
	* giving the fully qualified name of a UDT (an SQL structured type or
	* distinct type) and 2) the
	* <code>Class</code> object for the <code>SQLData</code> implementation
	* that defines how the UDT is to be mapped. The <i>map</i>
	* parameter does not have any effect for <code>Blob</code>,
	* <code>Clob</code>, <code>DATALINK</code>, or
	* <code>JAVA_OBJECT</code> types.
	* @throws SerialException if an error occurs serializing the
	* <code>Array</code> object
	* @throws SQLException if a database access error occurs or if the
	* <i>array</i> or the <i>map</i> values are <code>null</code>
	*/
	public SerialArray(Array array, Map<String,Class<?>> map)
	throws SerialException, SQLException
	{

	if ((array == null) \|\| (map == null)) {
	throw new SQLException("Cannot instantiate a SerialArray " +
	"object with null parameters");
	}

	if ((elements = (Object[])array.getArray()) == null) {
	throw new SQLException("Invalid Array object. Calls to Array.getArray() " +
	"return null value which cannot be serialized");
	}

	elements = (Object[])array.getArray(map);
	baseType = array.getBaseType();
	baseTypeName = array.getBaseTypeName();
	len = elements.length;

	switch (baseType) {
	case java.sql.Types.STRUCT:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialStruct((Struct)elements[i], map);
	}
	break;

	case java.sql.Types.ARRAY:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialArray((Array)elements[i], map);
	}
	break;

	case java.sql.Types.BLOB:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialBlob((Blob)elements[i]);
	}
	break;

	case java.sql.Types.CLOB:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialClob((Clob)elements[i]);
	}
	break;

	case java.sql.Types.DATALINK:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialDatalink((URL)elements[i]);
	}
	break;

	case java.sql.Types.JAVA_OBJECT:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialJavaObject(elements[i]);
	}
	}
	}

	/**
	* This method frees the {@code SerialArray} object and releases the
	* resources that it holds. The object is invalid once the {@code free}
	* method is called. <p> If {@code free} is called multiple times, the
	* subsequent calls to {@code free} are treated as a no-op. </P>
	*
	* @throws SQLException if an error occurs releasing the SerialArray's resources
	* @since 1.6
	*/
	public void free() throws SQLException {
	if (elements != null) {
	elements = null;
	baseTypeName= null;
	}
	}

	/**
	* Constructs a new <code>SerialArray</code> object from the given
	* <code>Array</code> object.
	* <P>
	* This constructor does not do custom mapping. If the base type of the array
	* is an SQL structured type and custom mapping is desired, the constructor
	* <code>SerialArray(Array array, Map map)</code> should be used.
	* <P>
	* The new <code>SerialArray</code>
	* object contains the same elements as the <code>Array</code> object
	* from which it is built, except when the base type is the SQL type
	* <code>BLOB</code>,
	* <code>CLOB</code>, <code>DATALINK</code> or <code>JAVA_OBJECT</code>.
	* In this case, each element in the new
	* <code>SerialArray</code> object is the appropriate serialized form,
	* that is, a <code>SerialBlob</code>, <code>SerialClob</code>,
	* <code>SerialDatalink</code>, or <code>SerialJavaObject</code> object.
	* <P>
	* Note: (1) The <code>Array</code> object from which a <code>SerialArray</code>
	* object is created must have materialized the SQL <code>ARRAY</code> value's
	* data on the client before it is passed to the constructor. Otherwise,
	* the new <code>SerialArray</code> object will contain no data.
	* <p>
	* Note: (2) The <code>Array</code> object supplied to this constructor cannot
	* return <code>null</code> for any <code>Array.getArray()</code> methods.
	* <code>SerialArray</code> cannot serialize <code>null</code> array values.
	*
	* @param array the <code>Array</code> object to be serialized
	* @throws SerialException if an error occurs serializing the
	* <code>Array</code> object
	* @throws SQLException if a database access error occurs or the
	* <i>array</i> parameter is <code>null</code>.
	*/
	public SerialArray(Array array) throws SerialException, SQLException {
	if (array == null) {
	throw new SQLException("Cannot instantiate a SerialArray " +
	"object with a null Array object");
	}

	if ((elements = (Object[])array.getArray()) == null) {
	throw new SQLException("Invalid Array object. Calls to Array.getArray() " +
	"return null value which cannot be serialized");
	}

	//elements = (Object[])array.getArray();
	baseType = array.getBaseType();
	baseTypeName = array.getBaseTypeName();
	len = elements.length;

	switch (baseType) {

	case java.sql.Types.BLOB:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialBlob((Blob)elements[i]);
	}
	break;

	case java.sql.Types.CLOB:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialClob((Clob)elements[i]);
	}
	break;

	case java.sql.Types.DATALINK:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialDatalink((URL)elements[i]);
	}
	break;

	case java.sql.Types.JAVA_OBJECT:
	for (int i = 0; i < len; i++) {
	elements[i] = new SerialJavaObject(elements[i]);
	}
	break;

	}


	}

	/**
	* Returns a new array that is a copy of this <code>SerialArray</code>
	* object.
	*
	* @return a copy of this <code>SerialArray</code> object as an
	* <code>Object</code> in the Java programming language
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public Object getArray() throws SerialException {
	isValid();
	Object dst = new Object[len];
	System.arraycopy((Object)elements, 0, dst, 0, len);
	return dst;
	}

	/**
	* Returns a new array that is a copy of this <code>SerialArray</code>
	* object, using the given type map for the custom
	* mapping of each element when the elements are SQL UDTs.
	* <P>
	* This method does custom mapping if the array elements are a UDT
	* and the given type map has an entry for that UDT.
	* Custom mapping is recursive,
	* meaning that if, for instance, an element of an SQL structured type
	* is an SQL structured type that itself has an element that is an SQL
	* structured type, each structured type that has a custom mapping will be
	* mapped according to the given type map.
	*
	* @param map a <code>java.util.Map</code> object in which
	* each entry consists of 1) a <code>String</code> object
	* giving the fully qualified name of a UDT and 2) the
	* <code>Class</code> object for the <code>SQLData</code> implementation
	* that defines how the UDT is to be mapped
	* @return a copy of this <code>SerialArray</code> object as an
	* <code>Object</code> in the Java programming language
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public Object getArray(Map<String, Class<?>> map) throws SerialException {
	isValid();
	Object dst[] = new Object[len];
	System.arraycopy((Object)elements, 0, dst, 0, len);
	return dst;
	}

	/**
	* Returns a new array that is a copy of a slice
	* of this <code>SerialArray</code> object, starting with the
	* element at the given index and containing the given number
	* of consecutive elements.
	*
	* @param index the index into this <code>SerialArray</code> object
	* of the first element to be copied;
	* the index of the first element is <code>0</code>
	* @param count the number of consecutive elements to be copied, starting
	* at the given index
	* @return a copy of the designated elements in this <code>SerialArray</code>
	* object as an <code>Object</code> in the Java programming language
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public Object getArray(long index, int count) throws SerialException {
	isValid();
	Object dst = new Object[count];
	System.arraycopy((Object)elements, (int)index, dst, 0, count);
	return dst;
	}

	/**
	* Returns a new array that is a copy of a slice
	* of this <code>SerialArray</code> object, starting with the
	* element at the given index and containing the given number
	* of consecutive elements.
	* <P>
	* This method does custom mapping if the array elements are a UDT
	* and the given type map has an entry for that UDT.
	* Custom mapping is recursive,
	* meaning that if, for instance, an element of an SQL structured type
	* is an SQL structured type that itself has an element that is an SQL
	* structured type, each structured type that has a custom mapping will be
	* mapped according to the given type map.
	*
	* @param index the index into this <code>SerialArray</code> object
	* of the first element to be copied; the index of the
	* first element in the array is <code>0</code>
	* @param count the number of consecutive elements to be copied, starting
	* at the given index
	* @param map a <code>java.util.Map</code> object in which
	* each entry consists of 1) a <code>String</code> object
	* giving the fully qualified name of a UDT and 2) the
	* <code>Class</code> object for the <code>SQLData</code> implementation
	* that defines how the UDT is to be mapped
	* @return a copy of the designated elements in this <code>SerialArray</code>
	* object as an <code>Object</code> in the Java programming language
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public Object getArray(long index, int count, Map<String,Class<?>> map)
	throws SerialException
	{
	isValid();
	Object dst = new Object[count];
	System.arraycopy((Object)elements, (int)index, dst, 0, count);
	return dst;
	}

	/**
	* Retrieves the SQL type of the elements in this <code>SerialArray</code>
	* object. The <code>int</code> returned is one of the constants in the class
	* <code>java.sql.Types</code>.
	*
	* @return one of the constants in <code>java.sql.Types</code>, indicating
	* the SQL type of the elements in this <code>SerialArray</code> object
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public int getBaseType() throws SerialException {
	isValid();
	return baseType;
	}

	/**
	* Retrieves the DBMS-specific type name for the elements in this
	* <code>SerialArray</code> object.
	*
	* @return the SQL type name used by the DBMS for the base type of this
	* <code>SerialArray</code> object
	* @throws SerialException if an error occurs;
	* if {@code free} had previously been called on this object
	*/
	public String getBaseTypeName() throws SerialException {
	isValid();
	return baseTypeName;
	}

	/**
	* Retrieves a <code>ResultSet</code> object holding the elements of
	* the subarray that starts at
	* index <i>index</i> and contains up to <i>count</i> successive elements.
	* This method uses the connection's type map to map the elements of
	* the array if the map contains
	* an entry for the base type. Otherwise, the standard mapping is used.
	*
	* @param index the index into this <code>SerialArray</code> object
	* of the first element to be copied; the index of the
	* first element in the array is <code>0</code>
	* @param count the number of consecutive elements to be copied, starting
	* at the given index
	* @return a <code>ResultSet</code> object containing the designated
	* elements in this <code>SerialArray</code> object, with a
	* separate row for each element
	* @throws SerialException if called with the cause set to
	* {@code UnsupportedOperationException}
	*/
	public ResultSet getResultSet(long index, int count) throws SerialException {
	SerialException se = new SerialException();
	se.initCause(new UnsupportedOperationException());
	throw se;
	}

	/**
	*
	* Retrieves a <code>ResultSet</code> object that contains all of
	* the elements of the SQL <code>ARRAY</code>
	* value represented by this <code>SerialArray</code> object. This method uses
	* the specified map for type map customizations unless the base type of the
	* array does not match a user-defined type (UDT) in <i>map</i>, in
	* which case it uses the
	* standard mapping. This version of the method <code>getResultSet</code>
	* uses either the given type map or the standard mapping; it never uses the
	* type map associated with the connection.
	*
	* @param map a <code>java.util.Map</code> object in which
	* each entry consists of 1) a <code>String</code> object
	* giving the fully qualified name of a UDT and 2) the
	* <code>Class</code> object for the <code>SQLData</code> implementation
	* that defines how the UDT is to be mapped
	* @return a <code>ResultSet</code> object containing all of the
	* elements in this <code>SerialArray</code> object, with a
	* separate row for each element
	* @throws SerialException if called with the cause set to
	* {@code UnsupportedOperationException}
	*/
	public ResultSet getResultSet(Map<String, Class<?>> map)
	throws SerialException
	{
	SerialException se = new SerialException();
	se.initCause(new UnsupportedOperationException());
	throw se;
	}

	/**
	* Retrieves a <code>ResultSet</code> object that contains all of
	* the elements in the <code>ARRAY</code> value that this
	* <code>SerialArray</code> object represents.
	* If appropriate, the elements of the array are mapped using the connection's
	* type map; otherwise, the standard mapping is used.
	*
	* @return a <code>ResultSet</code> object containing all of the
	* elements in this <code>SerialArray</code> object, with a
	* separate row for each element
	* @throws SerialException if called with the cause set to
	* {@code UnsupportedOperationException}
	*/
	public ResultSet getResultSet() throws SerialException {
	SerialException se = new SerialException();
	se.initCause(new UnsupportedOperationException());
	throw se;
	}


	/**
	* Retrieves a result set holding the elements of the subarray that starts at
	* Retrieves a <code>ResultSet</code> object that contains a subarray of the
	* elements in this <code>SerialArray</code> object, starting at
	* index <i>index</i> and containing up to <i>count</i> successive
	* elements. This method uses
	* the specified map for type map customizations unless the base type of the
	* array does not match a user-defined type (UDT) in <i>map</i>, in
	* which case it uses the
	* standard mapping. This version of the method <code>getResultSet</code> uses
	* either the given type map or the standard mapping; it never uses the type
	* map associated with the connection.
	*
	* @param index the index into this <code>SerialArray</code> object
	* of the first element to be copied; the index of the
	* first element in the array is <code>0</code>
	* @param count the number of consecutive elements to be copied, starting
	* at the given index
	* @param map a <code>java.util.Map</code> object in which
	* each entry consists of 1) a <code>String</code> object
	* giving the fully qualified name of a UDT and 2) the
	* <code>Class</code> object for the <code>SQLData</code> implementation
	* that defines how the UDT is to be mapped
	* @return a <code>ResultSet</code> object containing the designated
	* elements in this <code>SerialArray</code> object, with a
	* separate row for each element
	* @throws SerialException if called with the cause set to
	* {@code UnsupportedOperationException}
	*/
	public ResultSet getResultSet(long index, int count,
	Map<String,Class<?>> map)
	throws SerialException
	{
	SerialException se = new SerialException();
	se.initCause(new UnsupportedOperationException());
	throw se;
	}


	/**
	* Compares this SerialArray to the specified object. The result is {@code
	* true} if and only if the argument is not {@code null} and is a {@code
	* SerialArray} object whose elements are identical to this object's elements
	*
	* @param obj The object to compare this {@code SerialArray} against
	*
	* @return {@code true} if the given object represents a {@code SerialArray}
	* equivalent to this SerialArray, {@code false} otherwise
	*
	*/
	public boolean equals(Object obj) {
	if (this == obj) {
	return true;
	}

	if (obj instanceof SerialArray) {
	SerialArray sa = (SerialArray)obj;
	return baseType == sa.baseType &&
	baseTypeName.equals(sa.baseTypeName) &&
	Arrays.equals(elements, sa.elements);
	}
	return false;
	}

	/**
	* Returns a hash code for this SerialArray. The hash code for a
	* {@code SerialArray} object is computed using the hash codes
	* of the elements of the {@code SerialArray} object
	*
	* @return a hash code value for this object.
	*/
	public int hashCode() {
	return (((31 + Arrays.hashCode(elements)) * 31 + len) * 31 +
	baseType) * 31 + baseTypeName.hashCode();
	}

	/**
	* Returns a clone of this {@code SerialArray}. The copy will contain a
	* reference to a clone of the underlying objects array, not a reference
	* to the original underlying object array of this {@code SerialArray} object.
	*
	* @return a clone of this SerialArray
	*/
	public Object clone() {
	try {
	SerialArray sa = (SerialArray) super.clone();
	sa.elements = (elements != null) ? Arrays.copyOf(elements, len) : null;
	return sa;
	} catch (CloneNotSupportedException ex) {
	// this shouldn't happen, since we are Cloneable
	throw new InternalError();
	}

	}

	/**
	* readObject is called to restore the state of the {@code SerialArray} from
	* a stream.
	* @param s the {@code ObjectInputStream} to read from.
	*
	* @throws ClassNotFoundException if the class of a serialized object
	* could not be found.
	* @throws IOException if an I/O error occurs.
	*/
	private void readObject(ObjectInputStream s)
	throws IOException, ClassNotFoundException {

	ObjectInputStream.GetField fields = s.readFields();
	Object[] tmp = (Object[])fields.get("elements", null);
	if (tmp == null)
	throw new InvalidObjectException("elements is null and should not be!");
	elements = tmp.clone();
	len = fields.get("len", 0);
	if(elements.length != len)
	throw new InvalidObjectException("elements is not the expected size");

	baseType = fields.get("baseType", 0);
	baseTypeName = (String)fields.get("baseTypeName", null);
	}

	/**
	* writeObject is called to save the state of the {@code SerialArray}
	* to a stream.
	* @param s the {@code ObjectOutputStream} to write to.
	* @throws IOException if an I/O error occurs.
	*/
	private void writeObject(ObjectOutputStream s)
	throws IOException {

	ObjectOutputStream.PutField fields = s.putFields();
	fields.put("elements", elements);
	fields.put("len", len);
	fields.put("baseType", baseType);
	fields.put("baseTypeName", baseTypeName);
	s.writeFields();
	}

	/**
	* Check to see if this object had previously had its {@code free} method
	* called
	*
	* @throws SerialException
	*/
	private void isValid() throws SerialException {
	if (elements == null) {
	throw new SerialException("Error: You cannot call a method on a "
	+ "SerialArray instance once free() has been called.");
	}
	}

	/**
	* The identifier that assists in the serialization of this <code>SerialArray</code>
	* object.
	*/
	static final long serialVersionUID = -8466174297270688520L;
	}

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