/* * Copyright (c) 2003, 2004, 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>. * <P> * <p> * <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. * <P> * <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>. * <P> * <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> * <P> */ 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 occured 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 */Lines 1–500 of 537. Load more
/* * Copyright (c) 2003, 2004, 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>. * <P> * <p> * <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. * <P> * <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>. * <P> * <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> * <P> */ 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 occured 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 */