Java tutorial
/* * Copyright (c) 2003, 2019, 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 org.xml.sax.*; /** * The standard interface that all implementations of a {@code WebRowSet} * must implement. * * <h2>1.0 Overview</h2> * The {@code WebRowSetImpl} provides the standard * reference implementation, which may be extended if required. * <P> * The standard WebRowSet XML Schema definition is available at the following * URI: * <ul> * <li> * <a href="http://java.sun.com/xml/ns/jdbc/webrowset.xsd">http://java.sun.com/xml/ns/jdbc/webrowset.xsd</a> * </li> * </ul> * It describes the standard XML document format required when describing a * {@code RowSet} object in XML and must be used be all standard implementations * of the {@code WebRowSet} interface to ensure interoperability. In addition, * the {@code WebRowSet} schema uses specific SQL/XML Schema annotations, * thus ensuring greater cross * platform interoperability. This is an effort currently under way at the ISO * organization. The SQL/XML definition is available at the following URI: * <ul> * <li> * <a href="http://standards.iso.org/iso/9075/2002/12/sqlxml.xsd">http://standards.iso.org/iso/9075/2002/12/sqlxml.xsd</a> * </li> * </ul> * The schema definition describes the internal data of a {@code RowSet} object * in three distinct areas: * <UL> * <li>properties - These properties describe the standard synchronization * provider properties in addition to the more general {@code RowSet} properties. * </li> * <li>metadata - This describes the metadata associated with the tabular structure governed by a * {@code WebRowSet} object. The metadata described is closely aligned with the * metadata accessible in the underlying {@code java.sql.ResultSet} interface. * </li> * <li>data - This describes the original data (the state of data since the * last population * or last synchronization of the {@code WebRowSet} object) and the current * data. By keeping track of the delta between the original data and the current data, * a {@code WebRowSet} maintains the ability to synchronize changes * in its data back to the originating data source. * </li> * </ul> * * <h2>2.0 WebRowSet States</h2> * The following sections demonstrates how a {@code WebRowSet} implementation * should use the XML Schema to describe update, insert, and delete operations * and to describe the state of a {@code WebRowSet} object in XML. * * <h2>2.1 State 1 - Outputting a {@code WebRowSet} Object to XML</h2> * In this example, a {@code WebRowSet} object is created and populated with a simple 2 column, * 5 row table from a data source. Having the 5 rows in a {@code WebRowSet} object * makes it possible to describe them in XML. The * metadata describing the various standard JavaBeans properties as defined * in the RowSet interface plus the standard properties defined in * the {@code CachedRowSet}™ interface * provide key details that describe WebRowSet * properties. Outputting the WebRowSet object to XML using the standard * {@code writeXml} methods describes the internal properties as follows: * <PRE> * {@code * <properties> * <command>select co1, col2 from test_table</command> * <concurrency>1</concurrency> * <datasource/> * <escape-processing>true</escape-processing> * <fetch-direction>0</fetch-direction> * <fetch-size>0</fetch-size> * <isolation-level>1</isolation-level> * <key-columns/> * <map/> * <max-field-size>0</max-field-size> * <max-rows>0</max-rows> * <query-timeout>0</query-timeout> * <read-only>false</read-only> * <rowset-type>TRANSACTION_READ_UNCOMMITTED</rowset-type> * <show-deleted>false</show-deleted> * <table-name/> * <url>jdbc:thin:oracle</url> * <sync-provider> * <sync-provider-name>.com.rowset.provider.RIOptimisticProvider</sync-provider-name> * <sync-provider-vendor>Oracle Corporation</sync-provider-vendor> * <sync-provider-version>1.0</sync-provider-name> * <sync-provider-grade>LOW</sync-provider-grade> * <data-source-lock>NONE</data-source-lock> * </sync-provider> * </properties> * } </PRE> * The meta-data describing the make up of the WebRowSet is described * in XML as detailed below. Note both columns are described between the * {@code column-definition} tags. * <PRE> * {@code * <metadata> * <column-count>2</column-count> * <column-definition> * <column-index>1</column-index> * <auto-increment>false</auto-increment> * <case-sensitive>true</case-sensitive> * <currency>false</currency> * <nullable>1</nullable> * <signed>false</signed> * <searchable>true</searchable> * <column-display-size>10</column-display-size> * <column-label>COL1</column-label> * <column-name>COL1</column-name> * <schema-name/> * <column-precision>10</column-precision> * <column-scale>0</column-scale> * <table-name/> * <catalog-name/> * <column-type>1</column-type> * <column-type-name>CHAR</column-type-name> * </column-definition> * <column-definition> * <column-index>2</column-index> * <auto-increment>false</auto-increment> * <case-sensitive>false</case-sensitive> * <currency>false</currency> * <nullable>1</nullable> * <signed>true</signed> * <searchable>true</searchable> * <column-display-size>39</column-display-size> * <column-label>COL2</column-label> * <column-name>COL2</column-name> * <schema-name/> * <column-precision>38</column-precision> * <column-scale>0</column-scale> * <table-name/> * <catalog-name/> * <column-type>3</column-type> * <column-type-name>NUMBER</column-type-name> * </column-definition> * </metadata> * }</PRE> * Having detailed how the properties and metadata are described, the following details * how the contents of a {@code WebRowSet} object is described in XML. Note, that * this describes a {@code WebRowSet} object that has not undergone any * modifications since its instantiation. * A {@code currentRow} tag is mapped to each row of the table structure that the * {@code WebRowSet} object provides. A {@code columnValue} tag may contain * either the {@code stringData} or {@code binaryData} tag, according to * the SQL type that * the XML value is mapping back to. The {@code binaryData} tag contains data in the * Base64 encoding and is typically used for {@code BLOB} and {@code CLOB} type data. * <PRE> * {@code * <data> * <currentRow> * <columnValue> * firstrow * </columnValue> * <columnValue> * 1 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * secondrow * </columnValue> * <columnValue> * 2 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * thirdrow * </columnValue> * <columnValue> * 3 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * fourthrow * </columnValue> * <columnValue> * 4 * </columnValue> * </currentRow> * </data> * }</PRE> * <h2>2.2 State 2 - Deleting a Row</h2> * Deleting a row in a {@code WebRowSet} object involves simply moving to the row * to be deleted and then calling the method {@code deleteRow}, as in any other * {@code RowSet} object. The following * two lines of code, in which <i>wrs</i> is a {@code WebRowSet} object, delete * the third row. * <PRE> * wrs.absolute(3); * wrs.deleteRow(); * </PRE> * The XML description shows the third row is marked as a {@code deleteRow}, * which eliminates the third row in the {@code WebRowSet} object. * <PRE> * {@code * <data> * <currentRow> * <columnValue> * firstrow * </columnValue> * <columnValue> * 1 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * secondrow * </columnValue> * <columnValue> * 2 * </columnValue> * </currentRow> * <deleteRow> * <columnValue> * thirdrow * </columnValue> * <columnValue> * 3 * </columnValue> * </deleteRow> * <currentRow> * <columnValue> * fourthrow * </columnValue> * <columnValue> * 4 * </columnValue> * </currentRow> * </data> *} </PRE> * <h2>2.3 State 3 - Inserting a Row</h2> * A {@code WebRowSet} object can insert a new row by moving to the insert row, * calling the appropriate updater methods for each column in the row, and then * calling the method {@code insertRow}. * <PRE> * {@code * wrs.moveToInsertRow(); * wrs.updateString(1, "fifththrow"); * wrs.updateString(2, "5"); * wrs.insertRow(); * }</PRE> * The following code fragment changes the second column value in the row just inserted. * Note that this code applies when new rows are inserted right after the current row, * which is why the method {@code next} moves the cursor to the correct row. * Calling the method {@code acceptChanges} writes the change to the data source. * * <PRE> * {@code wrs.moveToCurrentRow(); * wrs.next(); * wrs.updateString(2, "V"); * wrs.acceptChanges(); * }</PRE> * Describing this in XML demonstrates where the Java code inserts a new row and then * performs an update on the newly inserted row on an individual field. * <PRE> * {@code * <data> * <currentRow> * <columnValue> * firstrow * </columnValue> * <columnValue> * 1 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * secondrow * </columnValue> * <columnValue> * 2 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * newthirdrow * </columnValue> * <columnValue> * III * </columnValue> * </currentRow> * <insertRow> * <columnValue> * fifthrow * </columnValue> * <columnValue> * 5 * </columnValue> * <updateValue> * V * </updateValue> * </insertRow> * <currentRow> * <columnValue> * fourthrow * </columnValue> * <columnValue> * 4 * </columnValue> * </currentRow> * </date> *} </PRE> * <h2>2.4 State 4 - Modifying a Row</h2> * Modifying a row produces specific XML that records both the new value and the * value that was replaced. The value that was replaced becomes the original value, * and the new value becomes the current value. The following * code moves the cursor to a specific row, performs some modifications, and updates * the row when complete. * <PRE> *{@code * wrs.absolute(5); * wrs.updateString(1, "new4thRow"); * wrs.updateString(2, "IV"); * wrs.updateRow(); * }</PRE> * In XML, this is described by the {@code modifyRow} tag. Both the original and new * values are contained within the tag for original row tracking purposes. * <PRE> * {@code * <data> * <currentRow> * <columnValue> * firstrow * </columnValue> * <columnValue> * 1 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * secondrow * </columnValue> * <columnValue> * 2 * </columnValue> * </currentRow> * <currentRow> * <columnValue> * newthirdrow * </columnValue> * <columnValue> * III * </columnValue> * </currentRow> * <currentRow> * <columnValue> * fifthrow * </columnValue> * <columnValue> * 5 * </columnValue> * </currentRow> * <modifyRow> * <columnValue> * fourthrow * </columnValue> * <updateValue> * new4thRow * </updateValue> * <columnValue> * 4 * </columnValue> * <updateValue> * IV * </updateValue> * </modifyRow> * </data> * }</PRE> * * @see javax.sql.rowset.JdbcRowSet * @see javax.sql.rowset.CachedRowSet * @see javax.sql.rowset.FilteredRowSet * @see javax.sql.rowset.JoinRowSet * @since 1.5 */ public interface WebRowSet extends CachedRowSet { /** * Reads a {@code WebRowSet} object in its XML format from the given * {@code Reader} object. * * @param reader the {@code java.io.Reader} stream from which this * {@code WebRowSet} object will be populated * @throws SQLException if a database access error occurs */ public void readXml(java.io.Reader reader) throws SQLException; /** * Reads a stream based XML input to populate this {@code WebRowSet} * object. * * @param iStream the {@code java.io.InputStream} from which this * {@code WebRowSet} object will be populated * @throws SQLException if a data source access error occurs * @throws IOException if an IO exception occurs */ public void readXml(java.io.InputStream iStream) throws SQLException, IOException; /** * Populates this {@code WebRowSet} object with * the contents of the given {@code ResultSet} object and writes its * data, properties, and metadata * to the given {@code Writer} object in XML format. * <p> * NOTE: The {@code WebRowSet} cursor may be moved to write out the * contents to the XML data source. If implemented in this way, the cursor <b>must</b> * be returned to its position just prior to the {@code writeXml()} call. * * @param rs the {@code ResultSet} object with which to populate this * {@code WebRowSet} object * @param writer the {@code java.io.Writer} object to write to. * @throws SQLException if an error occurs writing out the rowset * contents in XML format */ public void writeXml(ResultSet rs, java.io.Writer writer) throws SQLException; /** * Populates this {@code WebRowSet} object with * the contents of the given {@code ResultSet} object and writes its * data, properties, and metadata * to the given {@code OutputStream} object in XML format. * <p> * NOTE: The {@code WebRowSet} cursor may be moved to write out the * contents to the XML data source. If implemented in this way, the cursor <b>must</b> * be returned to its position just prior to the {@code writeXml()} call. * * @param rs the {@code ResultSet} object with which to populate this * {@code WebRowSet} object * @param oStream the {@code java.io.OutputStream} to write to * @throws SQLException if a data source access error occurs * @throws IOException if a IO exception occurs */ public void writeXml(ResultSet rs, java.io.OutputStream oStream) throws SQLException, IOException; /** * Writes the data, properties, and metadata for this {@code WebRowSet} object * to the given {@code Writer} object in XML format. * * @param writer the {@code java.io.Writer} stream to write to * @throws SQLException if an error occurs writing out the rowset * contents to XML */ public void writeXml(java.io.Writer writer) throws SQLException; /** * Writes the data, properties, and metadata for this {@code WebRowSet} object * to the given {@code OutputStream} object in XML format. * * @param oStream the {@code java.io.OutputStream} stream to write to * @throws SQLException if a data source access error occurs * @throws IOException if a IO exception occurs */ public void writeXml(java.io.OutputStream oStream) throws SQLException, IOException; /** * The public identifier for the XML Schema definition that defines the XML * tags and their valid values for a {@code WebRowSet} implementation. */ public static String PUBLIC_XML_SCHEMA = "--//Oracle Corporation//XSD Schema//EN"; /** * The URL for the XML Schema definition file that defines the XML tags and * their valid values for a {@code WebRowSet} implementation. */ public static String SCHEMA_SYSTEM_ID = "http://java.sun.com/xml/ns/jdbc/webrowset.xsd"; }