| /* |
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| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
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| * 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). |
| * |
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| |
| package javax.sql.rowset.spi; |
| |
| import javax.sql.*; |
| |
| /** |
| * The synchronization mechanism that provides reader/writer capabilities for |
| * disconnected <code>RowSet</code> objects. |
| * A <code>SyncProvider</code> implementation is a class that extends the |
| * <code>SyncProvider</code> abstract class. |
| * <P> |
| * A <code>SyncProvider</code> implementation is |
| * identified by a unique ID, which is its fully qualified class name. |
| * This name must be registered with the |
| * <code>SyncFactory</code> SPI, thus making the implementation available to |
| * all <code>RowSet</code> implementations. |
| * The factory mechanism in the reference implementation uses this name to instantiate |
| * the implementation, which can then provide a <code>RowSet</code> object with its |
| * reader (a <code>javax.sql.RowSetReader</code> object) and its writer (a |
| * <code>javax.sql.RowSetWriter</code> object). |
| * <P> |
| * The Jdbc <code>RowSet</code> Implementations specification provides two |
| * reference implementations of the <code>SyncProvider</code> abstract class: |
| * <code>RIOptimisticProvider</code> and <code>RIXMLProvider</code>. |
| * The <code>RIOptimisticProvider</code> can set any <code>RowSet</code> |
| * implementation with a <code>RowSetReader</code> object and a |
| * <code>RowSetWriter</code> object. However, only the <code>RIXMLProvider</code> |
| * implementation can set an <code>XmlReader</code> object and an |
| * <code>XmlWriter</code> object. A <code>WebRowSet</code> object uses the |
| * <code>XmlReader</code> object to read data in XML format to populate itself with that |
| * data. It uses the <code>XmlWriter</code> object to write itself to a stream or |
| * <code>java.io.Writer</code> object in XML format. |
| * <P> |
| * <h3>1.0 Naming Convention for Implementations</h3> |
| * As a guide to naming <code>SyncProvider</code> |
| * implementations, the following should be noted: |
| * <UL> |
| * <li>The name for a <code>SyncProvider</code> implementation |
| * is its fully qualified class name. |
| * <li>It is recommended that vendors supply a |
| * <code>SyncProvider</code> implementation in a package named <code>providers</code>. |
| * </UL> |
| * <p> |
| * For instance, if a vendor named Fred, Inc. offered a |
| * <code>SyncProvider</code> implementation, you could have the following: |
| * <PRE> |
| * Vendor name: Fred, Inc. |
| * Domain name of vendor: com.fred |
| * Package name: com.fred.providers |
| * SyncProvider implementation class name: HighAvailabilityProvider |
| * |
| * Fully qualified class name of SyncProvider implementation: |
| * com.fred.providers.HighAvailabilityProvider |
| * </PRE> |
| * <P> |
| * The following line of code uses the fully qualified name to register |
| * this implementation with the <code>SyncFactory</code> static instance. |
| * <PRE> |
| * SyncFactory.registerProvider( |
| * "com.fred.providers.HighAvailabilityProvider"); |
| * </PRE> |
| * <P> |
| * The default <code>SyncProvider</code> object provided with the reference |
| * implementation uses the following name: |
| * <pre> |
| * com.sun.rowset.providers.RIOptimisticProvider |
| * </pre> |
| * <p> |
| * A vendor can register a <code>SyncProvider</code> implementation class name |
| * with Sun Microsystems, Inc. by sending email to jdbc@sun.com. |
| * Sun will maintain a database listing the |
| * available <code>SyncProvider</code> implementations for use with compliant |
| * <code>RowSet</code> implementations. This database will be similar to the |
| * one already maintained to list available JDBC drivers. |
| * <P> |
| * Vendors should refer to the reference implementation synchronization |
| * providers for additional guidance on how to implement a new |
| * <code>SyncProvider</code> implementation. |
| * |
| * <h3>2.0 How a <code>RowSet</code> Object Gets Its Provider</h3> |
| * |
| * A disconnected <code>Rowset</code> object may get access to a |
| * <code>SyncProvider</code> object in one of the following two ways: |
| * <UL> |
| * <LI>Using a constructor<BR> |
| * <PRE> |
| * CachedRowSet crs = new CachedRowSet( |
| * "com.fred.providers.HighAvailabilitySyncProvider"); |
| * </PRE> |
| * <LI>Using the <code>setSyncProvider</code> method |
| * <PRE> |
| * CachedRowSet crs = new CachedRowSet(); |
| * crs.setSyncProvider("com.fred.providers.HighAvailabilitySyncProvider"); |
| * </PRE> |
| |
| * </UL> |
| * <p> |
| * By default, the reference implementations of the <code>RowSet</code> synchronization |
| * providers are always available to the Java platform. |
| * If no other pluggable synchronization providers have been correctly |
| * registered, the <code>SyncFactory</code> will automatically generate |
| * an instance of the default <code>SyncProvider</code> reference implementation. |
| * Thus, in the preceding code fragment, if no implementation named |
| * <code>com.fred.providers.HighAvailabilitySyncProvider</code> has been |
| * registered with the <code>SyncFactory</code> instance, <i>crs</i> will be |
| * assigned the default provider in the reference implementation, which is |
| * <code>com.sun.rowset.providers.RIOptimisticProvider</code>. |
| * <p> |
| * <h3>3.0 Violations and Synchronization Issues</h3> |
| * If an update between a disconnected <code>RowSet</code> object |
| * and a data source violates |
| * the original query or the underlying data source constraints, this will |
| * result in undefined behavior for all disconnected <code>RowSet</code> implementations |
| * and their designated <code>SyncProvider</code> implementations. |
| * Not defining the behavior when such violations occur offers greater flexibility |
| * for a <code>SyncProvider</code> |
| * implementation to determine its own best course of action. |
| * <p> |
| * A <code>SyncProvider</code> implementation |
| * may choose to implement a specific handler to |
| * handle a subset of query violations. |
| * However if an original query violation or a more general data source constraint |
| * violation is not handled by the <code>SyncProvider</code> implementation, |
| * all <code>SyncProvider</code> |
| * objects must throw a <code>SyncProviderException</code>. |
| * <p> |
| * <h3>4.0 Updatable SQL VIEWs</h3> |
| * It is possible for any disconnected or connected <code>RowSet</code> object to be populated |
| * from an SQL query that is formulated originally from an SQL <code>VIEW</code>. |
| * While in many cases it is possible for an update to be performed to an |
| * underlying view, such an update requires additional metadata, which may vary. |
| * The <code>SyncProvider</code> class provides two constants to indicate whether |
| * an implementation supports updating an SQL <code>VIEW</code>. |
| * <ul> |
| * <li><code><b>NONUPDATABLE_VIEW_SYNC</b></code> - Indicates that a <code>SyncProvider</code> |
| * implementation does not support synchronization with an SQL <code>VIEW</code> as the |
| * underlying source of data for the <code>RowSet</code> object. |
| * <li><code><b>UPDATABLE_VIEW_SYNC</b></code> - Indicates that a |
| * <code>SyncProvider</code> implementation |
| * supports synchronization with an SQL <code>VIEW</code> as the underlying source |
| * of data. |
| * </ul> |
| * <P> |
| * The default is for a <code>RowSet</code> object not to be updatable if it was |
| * populated with data from an SQL <code>VIEW</code>. |
| * <P> |
| * <h3>5.0 <code>SyncProvider</code> Constants</h3> |
| * The <code>SyncProvider</code> class provides three sets of constants that |
| * are used as return values or parameters for <code>SyncProvider</code> methods. |
| * <code>SyncProvider</code> objects may be implemented to perform synchronization |
| * between a <code>RowSet</code> object and its underlying data source with varying |
| * degrees of of care. The first group of constants indicate how synchronization |
| * is handled. For example, <code>GRADE_NONE</code> indicates that a |
| * <code>SyncProvider</code> object will not take any care to see what data is |
| * valid and will simply write the <code>RowSet</code> data to the data source. |
| * <code>GRADE_MODIFIED_AT_COMMIT</code> indicates that the provider will check |
| * only modified data for validity. Other grades check all data for validity |
| * or set locks when data is modified or loaded. |
| * <OL> |
| * <LI>Constants to indicate the synchronization grade of a |
| * <code>SyncProvider</code> object |
| * <UL> |
| * <LI>SyncProvider.GRADE_NONE |
| * <LI>SyncProvider.GRADE_MODIFIED_AT_COMMIT |
| * <LI>SyncProvider.GRADE_CHECK_ALL_AT_COMMIT |
| * <LI>SyncProvider.GRADE_LOCK_WHEN_MODIFIED |
| * <LI>SyncProvider.GRADE_LOCK_WHEN_LOADED |
| * </UL> |
| * <LI>Constants to indicate what locks are set on the data source |
| * <UL> |
| * <LI>SyncProvider.DATASOURCE_NO_LOCK |
| * <LI>SyncProvider.DATASOURCE_ROW_LOCK |
| * <LI>SyncProvider.DATASOURCE_TABLE_LOCK |
| * <LI>SyncProvider.DATASOURCE_DB_LOCK |
| * </UL> |
| * <LI>Constants to indicate whether a <code>SyncProvider</code> object can |
| * perform updates to an SQL <code>VIEW</code> <BR> |
| * These constants are explained in the preceding section (4.0). |
| * <UL> |
| * <LI>SyncProvider.UPDATABLE_VIEW_SYNC |
| * <LI>SyncProvider.NONUPDATABLE_VIEW_SYNC |
| * </UL> |
| * </OL> |
| * |
| * @author Jonathan Bruce |
| * @see javax.sql.rowset.spi.SyncFactory |
| * @see javax.sql.rowset.spi.SyncFactoryException |
| */ |
| public abstract class SyncProvider { |
| |
| /** |
| * Creates a default <code>SyncProvider</code> object. |
| */ |
| public SyncProvider() { |
| } |
| |
| /** |
| * Returns the unique identifier for this <code>SyncProvider</code> object. |
| * |
| * @return a <code>String</code> object with the fully qualified class name of |
| * this <code>SyncProvider</code> object |
| */ |
| public abstract String getProviderID(); |
| |
| /** |
| * Returns a <code>javax.sql.RowSetReader</code> object, which can be used to |
| * populate a <code>RowSet</code> object with data. |
| * |
| * @return a <code>javax.sql.RowSetReader</code> object |
| */ |
| public abstract RowSetReader getRowSetReader(); |
| |
| /** |
| * Returns a <code>javax.sql.RowSetWriter</code> object, which can be |
| * used to write a <code>RowSet</code> object's data back to the |
| * underlying data source. |
| * |
| * @return a <code>javax.sql.RowSetWriter</code> object |
| */ |
| public abstract RowSetWriter getRowSetWriter(); |
| |
| /** |
| * Returns a constant indicating the |
| * grade of synchronization a <code>RowSet</code> object can expect from |
| * this <code>SyncProvider</code> object. |
| * |
| * @return an int that is one of the following constants: |
| * SyncProvider.GRADE_NONE, |
| * SyncProvider.GRADE_CHECK_MODIFIED_AT_COMMIT, |
| * SyncProvider.GRADE_CHECK_ALL_AT_COMMIT, |
| * SyncProvider.GRADE_LOCK_WHEN_MODIFIED, |
| * SyncProvider.GRADE_LOCK_WHEN_LOADED |
| */ |
| public abstract int getProviderGrade(); |
| |
| |
| /** |
| * Sets a lock on the underlying data source at the level indicated by |
| * <i>datasource_lock</i>. This should cause the |
| * <code>SyncProvider</code> to adjust its behavior by increasing or |
| * decreasing the level of optimism it provides for a successful |
| * synchronization. |
| * |
| * @param datasource_lock one of the following constants indicating the severity |
| * level of data source lock required: |
| * <pre> |
| * SyncProvider.DATASOURCE_NO_LOCK, |
| * SyncProvider.DATASOURCE_ROW_LOCK, |
| * SyncProvider.DATASOURCE_TABLE_LOCK, |
| * SyncProvider.DATASOURCE_DB_LOCK, |
| * </pre> |
| * @throws SyncProviderException if an unsupported data source locking level |
| * is set. |
| * @see #getDataSourceLock |
| */ |
| public abstract void setDataSourceLock(int datasource_lock) |
| throws SyncProviderException; |
| |
| /** |
| * Returns the current data source lock severity level active in this |
| * <code>SyncProvider</code> implementation. |
| * |
| * @return a constant indicating the current level of data source lock |
| * active in this <code>SyncProvider</code> object; |
| * one of the following: |
| * <pre> |
| * SyncProvider.DATASOURCE_NO_LOCK, |
| * SyncProvider.DATASOURCE_ROW_LOCK, |
| * SyncProvider.DATASOURCE_TABLE_LOCK, |
| * SyncProvider.DATASOURCE_DB_LOCK |
| * </pre> |
| * @throws SyncProviderExceptiom if an error occurs determining the data |
| * source locking level. |
| * @see #setDataSourceLock |
| |
| */ |
| public abstract int getDataSourceLock() |
| throws SyncProviderException; |
| |
| /** |
| * Returns whether this <code>SyncProvider</code> implementation |
| * can perform synchronization between a <code>RowSet</code> object |
| * and the SQL <code>VIEW</code> in the data source from which |
| * the <code>RowSet</code> object got its data. |
| * |
| * @return an <code>int</code> saying whether this <code>SyncProvider</code> |
| * object supports updating an SQL <code>VIEW</code>; one of the |
| * following: |
| * SyncProvider.UPDATABLE_VIEW_SYNC, |
| * SyncProvider.NONUPDATABLE_VIEW_SYNC |
| */ |
| public abstract int supportsUpdatableView(); |
| |
| /** |
| * Returns the release version of this <code>SyncProvider</code> instance. |
| * |
| * @return a <code>String</code> detailing the release version of the |
| * <code>SyncProvider</code> implementation |
| */ |
| public abstract String getVersion(); |
| |
| /** |
| * Returns the vendor name of this <code>SyncProvider</code> instance |
| * |
| * @return a <code>String</code> detailing the vendor name of this |
| * <code>SyncProvider</code> implementation |
| */ |
| public abstract String getVendor(); |
| |
| /* |
| * Standard description of synchronization grades that a SyncProvider |
| * could provide. |
| */ |
| |
| /** |
| * Indicates that no synchronization with the originating data source is |
| * provided. A <code>SyncProvider</code> |
| * implementation returning this grade will simply attempt to write |
| * updates in the <code>RowSet</code> object to the underlying data |
| * source without checking the validity of any data. |
| * |
| */ |
| public static int GRADE_NONE = 1; |
| |
| /** |
| * Indicates a low level optimistic synchronization grade with |
| * respect to the originating data source. |
| * |
| * A <code>SyncProvider</code> implementation |
| * returning this grade will check only rows that have changed. |
| * |
| */ |
| public static int GRADE_CHECK_MODIFIED_AT_COMMIT = 2; |
| |
| /** |
| * Indicates a high level optimistic synchronization grade with |
| * respect to the originating data source. |
| * |
| * A <code>SyncProvider</code> implementation |
| * returning this grade will check all rows, including rows that have not |
| * changed. |
| */ |
| public static int GRADE_CHECK_ALL_AT_COMMIT = 3; |
| |
| /** |
| * Indicates a pessimistic synchronization grade with |
| * respect to the originating data source. |
| * |
| * A <code>SyncProvider</code> |
| * implementation returning this grade will lock the row in the originating |
| * data source. |
| */ |
| public static int GRADE_LOCK_WHEN_MODIFIED = 4; |
| |
| /** |
| * Indicates the most pessimistic synchronization grade with |
| * respect to the originating |
| * data source. A <code>SyncProvider</code> |
| * implementation returning this grade will lock the entire view and/or |
| * table affected by the original statement used to populate a |
| * <code>RowSet</code> object. |
| */ |
| public static int GRADE_LOCK_WHEN_LOADED = 5; |
| |
| /** |
| * Indicates that no locks remain on the originating data source. This is the default |
| * lock setting for all <code>SyncProvider</code> implementations unless |
| * otherwise directed by a <code>RowSet</code> object. |
| */ |
| public static int DATASOURCE_NO_LOCK = 1; |
| |
| /** |
| * Indicates that a lock is placed on the rows that are touched by the original |
| * SQL statement used to populate the <code>RowSet</code> object |
| * that is using this <code>SyncProvider</code> object. |
| */ |
| public static int DATASOURCE_ROW_LOCK = 2; |
| |
| /** |
| * Indicates that a lock is placed on all tables that are touched by the original |
| * SQL statement used to populate the <code>RowSet</code> object |
| * that is using this <code>SyncProvider</code> object. |
| */ |
| public static int DATASOURCE_TABLE_LOCK = 3; |
| |
| /** |
| * Indicates that a lock is placed on the entire data source that is the source of |
| * data for the <code>RowSet</code> object |
| * that is using this <code>SyncProvider</code> object. |
| */ |
| public static int DATASOURCE_DB_LOCK = 4; |
| |
| /** |
| * Indicates that a <code>SyncProvider</code> implementation |
| * supports synchronization between a <code>RowSet</code> object and |
| * the SQL <code>VIEW</code> used to populate it. |
| */ |
| public static int UPDATABLE_VIEW_SYNC = 5; |
| |
| /** |
| * Indicates that a <code>SyncProvider</code> implementation |
| * does <B>not</B> support synchronization between a <code>RowSet</code> |
| * object and the SQL <code>VIEW</code> used to populate it. |
| */ |
| public static int NONUPDATABLE_VIEW_SYNC = 6; |
| } |
