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	/*
	* Copyright (c) 2003, 2013, 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;

	import java.sql.*;
	import javax.sql.*;
	import javax.naming.*;
	import java.io.*;
	import java.math.*;
	import java.util.*;

	import javax.sql.rowset.*;

	/**
	* The <code>JoinRowSet</code> interface provides a mechanism for combining related
	* data from different <code>RowSet</code> objects into one <code>JoinRowSet</code>
	* object, which represents an SQL <code>JOIN</code>.
	* In other words, a <code>JoinRowSet</code> object acts as a
	* container for the data from <code>RowSet</code> objects that form an SQL
	* <code>JOIN</code> relationship.
	* <P>
	* The <code>Joinable</code> interface provides the methods for setting,
	* retrieving, and unsetting a match column, the basis for
	* establishing an SQL <code>JOIN</code> relationship. The match column may
	* alternatively be set by supplying it to the appropriate version of the
	* <code>JointRowSet</code> method <code>addRowSet</code>.
	*
	* <h3>1.0 Overview</h3>
	* Disconnected <code>RowSet</code> objects (<code>CachedRowSet</code> objects
	* and implementations extending the <code>CachedRowSet</code> interface)
	* do not have a standard way to establish an SQL <code>JOIN</code> between
	* <code>RowSet</code> objects without the expensive operation of
	* reconnecting to the data source. The <code>JoinRowSet</code>
	* interface is specifically designed to address this need.
	* <P>
	* Any <code>RowSet</code> object
	* can be added to a <code>JoinRowSet</code> object to become
	* part of an SQL <code>JOIN</code> relationship. This means that both connected
	* and disconnected <code>RowSet</code> objects can be part of a <code>JOIN</code>.
	* <code>RowSet</code> objects operating in a connected environment
	* (<code>JdbcRowSet</code> objects) are
	* encouraged to use the database to which they are already
	* connected to establish SQL <code>JOIN</code> relationships between
	* tables directly. However, it is possible for a
	* <code>JdbcRowSet</code> object to be added to a <code>JoinRowSet</code> object
	* if necessary.
	* <P>
	* Any number of <code>RowSet</code> objects can be added to an
	* instance of <code>JoinRowSet</code> provided that they
	* can be related in an SQL <code>JOIN</code>.
	* By definition, the SQL <code>JOIN</code> statement is used to
	* combine the data contained in two or more relational database tables based
	* upon a common attribute. The <code>Joinable</code> interface provides the methods
	* for establishing a common attribute, which is done by setting a
	* <i>match column</i>. The match column commonly coincides with
	* the primary key, but there is
	* no requirement that the match column be the same as the primary key.
	* By establishing and then enforcing column matches,
	* a <code>JoinRowSet</code> object establishes <code>JOIN</code> relationships
	* between <code>RowSet</code> objects without the assistance of an available
	* relational database.
	* <P>
	* The type of <code>JOIN</code> to be established is determined by setting
	* one of the <code>JoinRowSet</code> constants using the method
	* <code>setJoinType</code>. The following SQL <code>JOIN</code> types can be set:
	* <UL>
	* <LI><code>CROSS_JOIN</code>
	* <LI><code>FULL_JOIN</code>
	* <LI><code>INNER_JOIN</code> - the default if no <code>JOIN</code> type has been set
	* <LI><code>LEFT_OUTER_JOIN</code>
	* <LI><code>RIGHT_OUTER_JOIN</code>
	* </UL>
	* Note that if no type is set, the <code>JOIN</code> will automatically be an
	* inner join. The comments for the fields in the
	* <code>JoinRowSet</code> interface explain these <code>JOIN</code> types, which are
	* standard SQL <code>JOIN</code> types.
	*
	* <h3>2.0 Using a <code>JoinRowSet</code> Object for Creating a <code>JOIN</code></h3>
	* When a <code>JoinRowSet</code> object is created, it is empty.
	* The first <code>RowSet</code> object to be added becomes the basis for the
	* <code>JOIN</code> relationship.
	* Applications must determine which column in each of the
	* <code>RowSet</code> objects to be added to the <code>JoinRowSet</code> object
	* should be the match column. All of the
	* <code>RowSet</code> objects must contain a match column, and the values in
	* each match column must be ones that can be compared to values in the other match
	* columns. The columns do not have to have the same name, though they often do,
	* and they do not have to store the exact same data type as long as the data types
	* can be compared.
	* <P>
	* A match column can be be set in two ways:
	* <ul>
	* <li>By calling the <code>Joinable</code> method <code>setMatchColumn</code><br>
	* This is the only method that can set the match column before a <code>RowSet</code>
	* object is added to a <code>JoinRowSet</code> object. The <code>RowSet</code> object
	* must have implemented the <code>Joinable</code> interface in order to use the method
	* <code>setMatchColumn</code>. Once the match column value
	* has been set, this method can be used to reset the match column at any time.
	* <li>By calling one of the versions of the <code>JoinRowSet</code> method
	* <code>addRowSet</code> that takes a column name or number (or an array of
	* column names or numbers)<BR>
	* Four of the five <code>addRowSet</code> methods take a match column as a parameter.
	* These four methods set or reset the match column at the time a <code>RowSet</code>
	* object is being added to a <code>JoinRowSet</code> object.
	* </ul>
	* <h3>3.0 Sample Usage</h3>
	* <p>
	* The following code fragment adds two <code>CachedRowSet</code>
	* objects to a <code>JoinRowSet</code> object. Note that in this example,
	* no SQL <code>JOIN</code> type is set, so the default <code>JOIN</code> type,
	* which is <i>INNER_JOIN</i>, is established.
	* <p>
	* In the following code fragment, the table <code>EMPLOYEES</code>, whose match
	* column is set to the first column (<code>EMP_ID</code>), is added to the
	* <code>JoinRowSet</code> object <i>jrs</i>. Then
	* the table <code>ESSP_BONUS_PLAN</code>, whose match column is likewise
	* the <code>EMP_ID</code> column, is added. When this second
	* table is added to <i>jrs</i>, only the rows in
	* <code>ESSP_BONUS_PLAN</code> whose <code>EMP_ID</code> value matches an
	* <code>EMP_ID</code> value in the <code>EMPLOYEES</code> table are added.
	* In this case, everyone in the bonus plan is an employee, so all of the rows
	* in the table <code>ESSP_BONUS_PLAN</code> are added to the <code>JoinRowSet</code>
	* object. In this example, both <code>CachedRowSet</code> objects being added
	* have implemented the <code>Joinable</code> interface and can therefore call
	* the <code>Joinable</code> method <code>setMatchColumn</code>.
	* <PRE>
	* JoinRowSet jrs = new JoinRowSetImpl();
	*
	* ResultSet rs1 = stmt.executeQuery("SELECT * FROM EMPLOYEES");
	* CachedRowSet empl = new CachedRowSetImpl();
	* empl.populate(rs1);
	* empl.setMatchColumn(1);
	* jrs.addRowSet(empl);
	*
	* ResultSet rs2 = stmt.executeQuery("SELECT * FROM ESSP_BONUS_PLAN");
	* CachedRowSet bonus = new CachedRowSetImpl();
	* bonus.populate(rs2);
	* bonus.setMatchColumn(1); // EMP_ID is the first column
	* jrs.addRowSet(bonus);
	* </PRE>
	* <P>
	* At this point, <i>jrs</i> is an inside JOIN of the two <code>RowSet</code> objects
	* based on their <code>EMP_ID</code> columns. The application can now browse the
	* combined data as if it were browsing one single <code>RowSet</code> object.
	* Because <i>jrs</i> is itself a <code>RowSet</code> object, an application can
	* navigate or modify it using <code>RowSet</code> methods.
	* <PRE>
	* jrs.first();
	* int employeeID = jrs.getInt(1);
	* String employeeName = jrs.getString(2);
	* </PRE>
	* <P>
	* Note that because the SQL <code>JOIN</code> must be enforced when an application
	* adds a second or subsequent <code>RowSet</code> object, there
	* may be an initial degradation in performance while the <code>JOIN</code> is
	* being performed.
	* <P>
	* The following code fragment adds an additional <code>CachedRowSet</code> object.
	* In this case, the match column (<code>EMP_ID</code>) is set when the
	* <code>CachedRowSet</code> object is added to the <code>JoinRowSet</code> object.
	* <PRE>
	* ResultSet rs3 = stmt.executeQuery("SELECT * FROM 401K_CONTRIB");
	* CachedRowSet fourO1k = new CachedRowSetImpl();
	* four01k.populate(rs3);
	* jrs.addRowSet(four01k, 1);
	* </PRE>
	* <P>
	* The <code>JoinRowSet</code> object <i>jrs</i> now contains values from all three
	* tables. The data in each row in <i>four01k</i> in which the value for the
	* <code>EMP_ID</code> column matches a value for the <code>EMP_ID</code> column
	* in <i>jrs</i> has been added to <i>jrs</i>.
	*
	* <h3>4.0 <code>JoinRowSet</code> Methods</h3>
	* The <code>JoinRowSet</code> interface supplies several methods for adding
	* <code>RowSet</code> objects and for getting information about the
	* <code>JoinRowSet</code> object.
	* <UL>
	* <LI>Methods for adding one or more <code>RowSet</code> objects<BR>
	* These methods allow an application to add one <code>RowSet</code> object
	* at a time or to add multiple <code>RowSet</code> objects at one time. In
	* either case, the methods may specify the match column for each
	* <code>RowSet</code> object being added.
	* <LI>Methods for getting information<BR>
	* One method retrieves the <code>RowSet</code> objects in the
	* <code>JoinRowSet</code> object, and another method retrieves the
	* <code>RowSet</code> names. A third method retrieves either the SQL
	* <code>WHERE</code> clause used behind the scenes to form the
	* <code>JOIN</code> or a text description of what the <code>WHERE</code>
	* clause does.
	* <LI>Methods related to the type of <code>JOIN</code><BR>
	* One method sets the <code>JOIN</code> type, and five methods find out whether
	* the <code>JoinRowSet</code> object supports a given type.
	* <LI>A method to make a separate copy of the <code>JoinRowSet</code> object<BR>
	* This method creates a copy that can be persisted to the data source.
	* </UL>
	*
	*/

	public interface JoinRowSet extends WebRowSet {

	/**
	* Adds the given <code>RowSet</code> object to this <code>JoinRowSet</code>
	* object. If the <code>RowSet</code> object
	* is the first to be added to this <code>JoinRowSet</code>
	* object, it forms the basis of the <code>JOIN</code> relationship to be
	* established.
	* <P>
	* This method should be used only when the given <code>RowSet</code>
	* object already has a match column that was set with the <code>Joinable</code>
	* method <code>setMatchColumn</code>.
	* <p>
	* Note: A <code>Joinable</code> object is any <code>RowSet</code> object
	* that has implemented the <code>Joinable</code> interface.
	*
	* @param rowset the <code>RowSet</code> object that is to be added to this
	* <code>JoinRowSet</code> object; it must implement the
	* <code>Joinable</code> interface and have a match column set
	* @throws SQLException if (1) an empty rowset is added to the to this
	* <code>JoinRowSet</code> object, (2) a match column has not been
	* set for <i>rowset</i>, or (3) <i>rowset</i>
	* violates the active <code>JOIN</code>
	* @see Joinable#setMatchColumn
	*/
	public void addRowSet(Joinable rowset) throws SQLException;

	/**
	* Adds the given <code>RowSet</code> object to this <code>JoinRowSet</code>
	* object and sets the designated column as the match column for
	* the <code>RowSet</code> object. If the <code>RowSet</code> object
	* is the first to be added to this <code>JoinRowSet</code>
	* object, it forms the basis of the <code>JOIN</code> relationship to be
	* established.
	* <P>
	* This method should be used when <i>RowSet</i> does not already have a match
	* column set.
	*
	* @param rowset the <code>RowSet</code> object that is to be added to this
	* <code>JoinRowSet</code> object; it may implement the
	* <code>Joinable</code> interface
	* @param columnIdx an <code>int</code> that identifies the column to become the
	* match column
	* @throws SQLException if (1) <i>rowset</i> is an empty rowset or
	* (2) <i>rowset</i> violates the active <code>JOIN</code>
	* @see Joinable#unsetMatchColumn
	*/
	public void addRowSet(RowSet rowset, int columnIdx) throws SQLException;

	/**
	* Adds <i>rowset</i> to this <code>JoinRowSet</code> object and
	* sets the designated column as the match column. If <i>rowset</i>
	* is the first to be added to this <code>JoinRowSet</code>
	* object, it forms the basis for the <code>JOIN</code> relationship to be
	* established.
	* <P>
	* This method should be used when the given <code>RowSet</code> object
	* does not already have a match column.
	*
	* @param rowset the <code>RowSet</code> object that is to be added to this
	* <code>JoinRowSet</code> object; it may implement the
	* <code>Joinable</code> interface
	* @param columnName the <code>String</code> object giving the name of the
	* column to be set as the match column
	* @throws SQLException if (1) <i>rowset</i> is an empty rowset or
	* (2) the match column for <i>rowset</i> does not satisfy the
	* conditions of the <code>JOIN</code>
	*/
	public void addRowSet(RowSet rowset,
	String columnName) throws SQLException;

	/**
	* Adds one or more <code>RowSet</code> objects contained in the given
	* array of <code>RowSet</code> objects to this <code>JoinRowSet</code>
	* object and sets the match column for
	* each of the <code>RowSet</code> objects to the match columns
	* in the given array of column indexes. The first element in
	* <i>columnIdx</i> is set as the match column for the first
	* <code>RowSet</code> object in <i>rowset</i>, the second element of
	* <i>columnIdx</i> is set as the match column for the second element
	* in <i>rowset</i>, and so on.
	* <P>
	* The first <code>RowSet</code> object added to this <code>JoinRowSet</code>
	* object forms the basis for the <code>JOIN</code> relationship.
	* <P>
	* This method should be used when the given <code>RowSet</code> object
	* does not already have a match column.
	*
	* @param rowset an array of one or more <code>RowSet</code> objects
	* to be added to the <code>JOIN</code>; it may implement the
	* <code>Joinable</code> interface
	* @param columnIdx an array of <code>int</code> values indicating the index(es)
	* of the columns to be set as the match columns for the <code>RowSet</code>
	* objects in <i>rowset</i>
	* @throws SQLException if (1) an empty rowset is added to this
	* <code>JoinRowSet</code> object, (2) a match column is not set
	* for a <code>RowSet</code> object in <i>rowset</i>, or (3)
	* a <code>RowSet</code> object being added violates the active
	* <code>JOIN</code>
	*/
	public void addRowSet(RowSet[] rowset,
	int[] columnIdx) throws SQLException;

	/**
	* Adds one or more <code>RowSet</code> objects contained in the given
	* array of <code>RowSet</code> objects to this <code>JoinRowSet</code>
	* object and sets the match column for
	* each of the <code>RowSet</code> objects to the match columns
	* in the given array of column names. The first element in
	* <i>columnName</i> is set as the match column for the first
	* <code>RowSet</code> object in <i>rowset</i>, the second element of
	* <i>columnName</i> is set as the match column for the second element
	* in <i>rowset</i>, and so on.
	* <P>
	* The first <code>RowSet</code> object added to this <code>JoinRowSet</code>
	* object forms the basis for the <code>JOIN</code> relationship.
	* <P>
	* This method should be used when the given <code>RowSet</code> object(s)
	* does not already have a match column.
	*
	* @param rowset an array of one or more <code>RowSet</code> objects
	* to be added to the <code>JOIN</code>; it may implement the
	* <code>Joinable</code> interface
	* @param columnName an array of <code>String</code> values indicating the
	* names of the columns to be set as the match columns for the
	* <code>RowSet</code> objects in <i>rowset</i>
	* @throws SQLException if (1) an empty rowset is added to this
	* <code>JoinRowSet</code> object, (2) a match column is not set
	* for a <code>RowSet</code> object in <i>rowset</i>, or (3)
	* a <code>RowSet</code> object being added violates the active
	* <code>JOIN</code>
	*/
	public void addRowSet(RowSet[] rowset,
	String[] columnName) throws SQLException;

	/**
	* Returns a <code>Collection</code> object containing the
	* <code>RowSet</code> objects that have been added to this
	* <code>JoinRowSet</code> object.
	* This should return the 'n' number of RowSet contained
	* within the <code>JOIN</code> and maintain any updates that have occurred while in
	* this union.
	*
	* @return a <code>Collection</code> object consisting of the
	* <code>RowSet</code> objects added to this <code>JoinRowSet</code>
	* object
	* @throws SQLException if an error occurs generating the
	* <code>Collection</code> object to be returned
	*/
	public Collection<?> getRowSets() throws java.sql.SQLException;

	/**
	* Returns a <code>String</code> array containing the names of the
	* <code>RowSet</code> objects added to this <code>JoinRowSet</code>
	* object.
	*
	* @return a <code>String</code> array of the names of the
	* <code>RowSet</code> objects in this <code>JoinRowSet</code>
	* object
	* @throws SQLException if an error occurs retrieving the names of
	* the <code>RowSet</code> objects
	* @see CachedRowSet#setTableName
	*/
	public String[] getRowSetNames() throws java.sql.SQLException;

	/**
	* Creates a new <code>CachedRowSet</code> object containing the
	* data in this <code>JoinRowSet</code> object, which can be saved
	* to a data source using the <code>SyncProvider</code> object for
	* the <code>CachedRowSet</code> object.
	* <P>
	* If any updates or modifications have been applied to the JoinRowSet
	* the CachedRowSet returned by the method will not be able to persist
	* it's changes back to the originating rows and tables in the
	* in the datasource. The CachedRowSet instance returned should not
	* contain modification data and it should clear all properties of
	* it's originating SQL statement. An application should reset the
	* SQL statement using the <code>RowSet.setCommand</code> method.
	* <p>
	* In order to allow changes to be persisted back to the datasource
	* to the originating tables, the <code>acceptChanges</code> method
	* should be used and called on a JoinRowSet object instance. Implementations
	* can leverage the internal data and update tracking in their
	* implementations to interact with the SyncProvider to persist any
	* changes.
	*
	* @return a CachedRowSet containing the contents of the JoinRowSet
	* @throws SQLException if an error occurs assembling the CachedRowSet
	* object
	* @see javax.sql.RowSet
	* @see javax.sql.rowset.CachedRowSet
	* @see javax.sql.rowset.spi.SyncProvider
	*/
	public CachedRowSet toCachedRowSet() throws java.sql.SQLException;

	/**
	* Indicates if CROSS_JOIN is supported by a JoinRowSet
	* implementation
	*
	* @return true if the CROSS_JOIN is supported; false otherwise
	*/
	public boolean supportsCrossJoin();

	/**
	* Indicates if INNER_JOIN is supported by a JoinRowSet
	* implementation
	*
	* @return true is the INNER_JOIN is supported; false otherwise
	*/
	public boolean supportsInnerJoin();

	/**
	* Indicates if LEFT_OUTER_JOIN is supported by a JoinRowSet
	* implementation
	*
	* @return true is the LEFT_OUTER_JOIN is supported; false otherwise
	*/
	public boolean supportsLeftOuterJoin();

	/**
	* Indicates if RIGHT_OUTER_JOIN is supported by a JoinRowSet
	* implementation
	*
	* @return true is the RIGHT_OUTER_JOIN is supported; false otherwise
	*/
	public boolean supportsRightOuterJoin();

	/**
	* Indicates if FULL_JOIN is supported by a JoinRowSet
	* implementation
	*
	* @return true is the FULL_JOIN is supported; false otherwise
	*/
	public boolean supportsFullJoin();

	/**
	* Allow the application to adjust the type of <code>JOIN</code> imposed
	* on tables contained within the JoinRowSet object instance.
	* Implementations should throw a SQLException if they do
	* not support a given <code>JOIN</code> type.
	*
	* @param joinType the standard JoinRowSet.XXX static field definition
	* of a SQL <code>JOIN</code> to re-configure a JoinRowSet instance on
	* the fly.
	* @throws SQLException if an unsupported <code>JOIN</code> type is set
	* @see #getJoinType
	*/
	public void setJoinType(int joinType) throws SQLException;

	/**
	* Return a SQL-like description of the WHERE clause being used
	* in a JoinRowSet object. An implementation can describe
	* the WHERE clause of the SQL <code>JOIN</code> by supplying a SQL
	* strings description of <code>JOIN</code> or provide a textual
	* description to assist applications using a <code>JoinRowSet</code>
	*
	* @return whereClause a textual or SQL description of the logical
	* WHERE clause used in the JoinRowSet instance
	* @throws SQLException if an error occurs in generating a representation
	* of the WHERE clause.
	*/
	public String getWhereClause() throws SQLException;

	/**
	* Returns a <code>int</code> describing the set SQL <code>JOIN</code> type
	* governing this JoinRowSet instance. The returned type will be one of
	* standard JoinRowSet types: <code>CROSS_JOIN</code>, <code>INNER_JOIN</code>,
	* <code>LEFT_OUTER_JOIN</code>, <code>RIGHT_OUTER_JOIN</code> or
	* <code>FULL_JOIN</code>.
	*
	* @return joinType one of the standard JoinRowSet static field
	* definitions of a SQL <code>JOIN</code>. <code>JoinRowSet.INNER_JOIN</code>
	* is returned as the default <code>JOIN</code> type is no type has been
	* explicitly set.
	* @throws SQLException if an error occurs determining the SQL <code>JOIN</code>
	* type supported by the JoinRowSet instance.
	* @see #setJoinType
	*/
	public int getJoinType() throws SQLException;

	/**
	* An ANSI-style <code>JOIN</code> providing a cross product of two tables
	*/
	public static int CROSS_JOIN = 0;

	/**
	* An ANSI-style <code>JOIN</code> providing a inner join between two tables. Any
	* unmatched rows in either table of the join should be discarded.
	*/
	public static int INNER_JOIN = 1;

	/**
	* An ANSI-style <code>JOIN</code> providing a left outer join between two
	* tables. In SQL, this is described where all records should be
	* returned from the left side of the JOIN statement.
	*/
	public static int LEFT_OUTER_JOIN = 2;

	/**
	* An ANSI-style <code>JOIN</code> providing a right outer join between
	* two tables. In SQL, this is described where all records from the
	* table on the right side of the JOIN statement even if the table
	* on the left has no matching record.
	*/
	public static int RIGHT_OUTER_JOIN = 3;

	/**
	* An ANSI-style <code>JOIN</code> providing a a full JOIN. Specifies that all
	* rows from either table be returned regardless of matching
	* records on the other table.
	*/
	public static int FULL_JOIN = 4;


	}

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