- /*
- * @(#)SyncProvider.java 1.9 04/03/11
- *
- * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- 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;
- }