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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/**
*
* Provides the API for accessing and processing data stored in a
* data source (usually a relational database) using the
* Java™ programming language.
* This API includes a framework whereby different
* drivers can be installed dynamically to access different data sources.
* Although the JDBC™ API is mainly geared
* to passing SQL statements to a database, it provides for reading and
* writing data from any data source with a tabular format.
* The reader/writer facility, available through the
* <code>javax.sql.RowSet</code> group of interfaces, can be customized to
* use and update data from a spread sheet, flat file, or any other tabular
* data source.
*
* <h2>What the JDBC™ 4.3 API Includes</h2>
* The JDBC™ 4.3 API includes both
* the <code>java.sql</code> package, referred to as the JDBC core API,
* and the <code>javax.sql</code> package, referred to as the JDBC Optional
* Package API. This complete JDBC API
* is included in the Java™ Standard Edition (Java SE™), version 7.
* The <code>javax.sql</code> package extends the functionality of the JDBC API
* from a client-side API to a server-side API, and it is an essential part
* of the Java™ Enterprise Edition
* (Java EE™) technology.
*
* <h2>Versions</h2>
* The JDBC 4.3 API incorporates all of the previous JDBC API versions:
* <UL>
* <LI> The JDBC 4.2 API</li>
* <LI> The JDBC 4.1 API</li>
* <LI> The JDBC 4.0 API</li>
* <LI> The JDBC 3.0 API</li>
* <LI> The JDBC 2.1 core API</li>
* <LI> The JDBC 2.0 Optional Package API<br>
* (Note that the JDBC 2.1 core API and the JDBC 2.0 Optional Package
* API together are referred to as the JDBC 2.0 API.)</li>
* <LI> The JDBC 1.2 API</li>
* <LI> The JDBC 1.0 API</li>
* </UL>
* <P>
* Classes, interfaces, methods, fields, constructors, and exceptions
* have the following "since" tags that indicate when they were introduced
* into the Java platform. When these "since" tags are used in
* Javadoc™ comments for the JDBC API,
* they indicate the following:
* <UL>
* <LI>Since 9 -- new in the JDBC 4.3 API and part of the Java SE platform,
* version 9</li>
* <LI>Since 1.8 -- new in the JDBC 4.2 API and part of the Java SE platform,
* version 8</li>
* <LI>Since 1.7 -- new in the JDBC 4.1 API and part of the Java SE platform,
* version 7</li>
* <LI>Since 1.6 -- new in the JDBC 4.0 API and part of the Java SE platform,
* version 6</li>
* <LI>Since 1.4 -- new in the JDBC 3.0 API and part of the J2SE platform,
* version 1.4</li>
* <LI>Since 1.2 -- new in the JDBC 2.0 API and part of the J2SE platform,
* version 1.2</li>
* <LI>Since 1.1 or no "since" tag -- in the original JDBC 1.0 API and part of
* the JDK™, version 1.1</li>
* </UL>
* <P>
* <b>NOTE:</b> Many of the new features are optional; consequently, there is
* some variation in drivers and the features they support. Always
* check your driver's documentation to see whether it supports a feature before
* you try to use it.
* <P>
* <b>NOTE:</b> The class <code>SQLPermission</code> was added in the
* Java™ 2 SDK, Standard Edition,
* version 1.3 release. This class is used to prevent unauthorized
* access to the logging stream associated with the <code>DriverManager</code>,
* which may contain information such as table names, column data, and so on.
*
* <h2>What the <code>java.sql</code> Package Contains</h2>
* The <code>java.sql</code> package contains API for the following:
* <UL>
* <LI>Making a connection with a database via the <code>DriverManager</code> facility
* <UL>
* <LI><code>DriverManager</code> class -- makes a connection with a driver
* <LI><code>SQLPermission</code> class -- provides permission when code
* running within a Security Manager, such as an applet,
* attempts to set up a logging stream through the
* <code>DriverManager</code>
* <LI><code>Driver</code> interface -- provides the API for registering
* and connecting drivers based on JDBC technology ("JDBC drivers");
* generally used only by the <code>DriverManager</code> class
* <LI><code>DriverPropertyInfo</code> class -- provides properties for a
* JDBC driver; not used by the general user
* </UL>
* <LI>Sending SQL statements to a database
* <UL>
* <LI><code>Statement</code> -- used to send basic SQL statements
* <LI><code>PreparedStatement</code> -- used to send prepared statements or
* basic SQL statements (derived from <code>Statement</code>)
* <LI><code>CallableStatement</code> -- used to call database stored
* procedures (derived from <code>PreparedStatement</code>)
* <LI><code>Connection</code> interface -- provides methods for creating
* statements and managing connections and their properties
* <LI><code>Savepoint</code> -- provides savepoints in a transaction
*
* </UL>
* <LI>Retrieving and updating the results of a query
* <UL>
* <LI><code>ResultSet</code> interface
* </UL>
* <LI>Standard mappings for SQL types to classes and interfaces in the
* Java programming language
* <UL>
* <LI><code>Array</code> interface -- mapping for SQL <code>ARRAY</code>
* <LI><code>Blob</code> interface -- mapping for SQL <code>BLOB</code>
* <LI><code>Clob</code> interface -- mapping for SQL <code>CLOB</code>
* <LI><code>Date</code> class -- mapping for SQL <code>DATE</code>
* <LI><code>NClob</code> interface -- mapping for SQL <code>NCLOB</code>
* <LI><code>Ref</code> interface -- mapping for SQL <code>REF</code>
* <LI><code>RowId</code> interface -- mapping for SQL <code>ROWID</code>
* <LI><code>Struct</code> interface -- mapping for SQL <code>STRUCT</code>
* <LI><code>SQLXML</code> interface -- mapping for SQL <code>XML</code>
* <LI><code>Time</code> class -- mapping for SQL <code>TIME</code>
* <LI><code>Timestamp</code> class -- mapping for SQL <code>TIMESTAMP</code>
* <LI><code>Types</code> class -- provides constants for SQL types
* </UL>
* <LI>Custom mapping an SQL user-defined type (UDT) to a class in the
* Java programming language
* <UL>
* <LI><code>SQLData</code> interface -- specifies the mapping of
* a UDT to an instance of this class
* <LI><code>SQLInput</code> interface -- provides methods for reading
* UDT attributes from a stream
* <LI><code>SQLOutput</code> interface -- provides methods for writing
* UDT attributes back to a stream
* </UL>
* <LI>Metadata
* <UL>
* <LI><code>DatabaseMetaData</code> interface -- provides information
* about the database
* <LI><code>ResultSetMetaData</code> interface -- provides information
* about the columns of a <code>ResultSet</code> object
* <LI><code>ParameterMetaData</code> interface -- provides information
* about the parameters to <code>PreparedStatement</code> commands
* </UL>
* <LI>Exceptions
* <UL>
* <LI><code>SQLException</code> -- thrown by most methods when there
* is a problem accessing data and by some methods for other reasons
* <LI><code>SQLWarning</code> -- thrown to indicate a warning
* <LI><code>DataTruncation</code> -- thrown to indicate that data may have
* been truncated
* <LI><code>BatchUpdateException</code> -- thrown to indicate that not all
* commands in a batch update executed successfully
* </UL>
* </UL>
*
* <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.3 API</h3>
* <UL>
* <LI>Added <code>Sharding</code> support</LI>
* <LI>Enhanced <code>Connection</code> to be able to provide hints
* to the driver that a request, an independent unit of work,
* is beginning or ending</LI>
* <LI>Enhanced <code>DatabaseMetaData</code> to determine if Sharding is
* supported</LI>
* <LI>Added the method <code>drivers</code> to <code>DriverManager</code>
* to return a Stream of the currently loaded and
* available JDBC drivers</LI>
* <LI>Added support to <code>Statement</code> for enquoting literals
* and simple identifiers</LI>
* <LI>Clarified the Java SE version that methods were deprecated</LI>
* </UL>
*
* <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.2 API</h3>
* <UL>
* <LI>Added <code>JDBCType</code> enum and <code>SQLType</code> interface</li>
* <LI>Support for <code>REF CURSORS</code> in <code>CallableStatement</code>
* </LI>
* <LI><code>DatabaseMetaData</code> methods to return maximum Logical LOB size
* and if Ref Cursors are supported</LI>
* <LI>Added support for large update counts</LI>
*
* </UL>
*
* <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.1 API</h3>
* <UL>
* <LI>Allow <code>Connection</code>,
* <code>ResultSet</code> and <code>Statement</code> objects to be
* used with the try-with-resources statement</LI>
* <LI>Support added to <code>CallableStatement</code> and
* <code>ResultSet</code> to specify the Java type to convert to via the
* <code>getObject</code> method</LI>
* <LI><code>DatabaseMetaData</code> methods to return PseudoColumns and if a
* generated key is always returned</LI>
* <LI>Added support to <code>Connection</code> to specify a database schema,
* abort and timeout a physical connection.</LI>
* <LI>Added support to close a <code>Statement</code> object when its dependent
* objects have been closed</LI>
* <LI>Support for obtaining the parent logger for a <code>Driver</code>,
* <code>DataSource</code>, <code>ConnectionPoolDataSource</code> and
* <code>XADataSource</code></LI>
*
* </UL>
* <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.0 API</h3>
* <UL>
* <LI>auto java.sql.Driver discovery -- no longer need to load a
* <code>java.sql.Driver</code> class via <code>Class.forName</code>
* <LI>National Character Set support added
* <li>Support added for the SQL:2003 XML data type
* <lI>SQLException enhancements -- Added support for cause chaining; New SQLExceptions
* added for common SQLState class value codes
* <li>Enhanced Blob/Clob functionality -- Support provided to create and free a Blob/Clob instance
* as well as additional methods added to improve accessibility
* <li>Support added for accessing a SQL ROWID
* <li>Support added to allow a JDBC application to access an instance of a JDBC resource
* that has been wrapped by a vendor, usually in an application server or connection
* pooling environment.
* <li>Availability to be notified when a <code>PreparedStatement</code> that is associated
* with a <code>PooledConnection</code> has been closed or the driver determines is invalid
*
*
* </UL>
*
*
* <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 3.0 API</h3>
* <UL>
* <LI>Pooled statements -- reuse of statements associated with a pooled
* connection
* <LI>Savepoints -- allow a transaction to be rolled back to a designated
* savepoint
* <LI>Properties defined for <code>ConnectionPoolDataSource</code> -- specify
* how connections are to be pooled
* <LI>Metadata for parameters of a <code>PreparedStatement</code> object
* <LI>Ability to retrieve values from automatically generated columns
* <LI>Ability to have multiple <code>ResultSet</code> objects
* returned from <code>CallableStatement</code> objects open at the
* same time
* <LI>Ability to identify parameters to <code>CallableStatement</code>
* objects by name as well as by index
* <LI><code>ResultSet</code> holdability -- ability to specify whether cursors
* should be held open or closed at the end of a transaction
* <LI>Ability to retrieve and update the SQL structured type instance that a
* <code>Ref</code> object references
* <LI>Ability to programmatically update <code>BLOB</code>,
* <code>CLOB</code>, <code>ARRAY</code>, and <code>REF</code> values.
* <LI>Addition of the <code>java.sql.Types.DATALINK</code> data type --
* allows JDBC drivers access to objects stored outside a data source
* <LI>Addition of metadata for retrieving SQL type hierarchies
* </UL>
*
* <h3><code>java.sql</code> Features Introduced in the JDBC 2.1 Core API</h3>
* <UL>
* <LI>Scrollable result sets--using new methods in the <code>ResultSet</code>
* interface that allow the cursor to be moved to a particular row or to a
* position relative to its current position
* <LI>Batch updates
* <LI>Programmatic updates--using <code>ResultSet</code> updater methods
* <LI>New data types--interfaces mapping the SQL3 data types
* <LI>Custom mapping of user-defined types (UDTs)
* <LI>Miscellaneous features, including performance hints, the use of character
* streams, full precision for <code>java.math.BigDecimal</code> values,
* additional security, and
* support for time zones in date, time, and timestamp values.
* </UL>
*
* <h3><code>javax.sql</code> Features Introduced in the JDBC 2.0 Optional
* Package API</h3>
* <UL>
* <LI>The <code>DataSource</code> interface as a means of making a connection. The
* Java Naming and Directory Interface™
* (JNDI) is used for registering a <code>DataSource</code> object with a
* naming service and also for retrieving it.
* <LI>Pooled connections -- allowing connections to be used and reused
* <LI>Distributed transactions -- allowing a transaction to span diverse
* DBMS servers
* <LI><code>RowSet</code> technology -- providing a convenient means of
* handling and passing data
* </UL>
*
*
* <h3>Custom Mapping of UDTs</h3>
* A user-defined type (UDT) defined in SQL can be mapped to a class in the Java
* programming language. An SQL structured type or an SQL <code>DISTINCT</code>
* type are the UDTs that may be custom mapped. The following three
* steps set up a custom mapping:
* <ol>
* <li>Defining the SQL structured type or <code>DISTINCT</code> type in SQL
* <li>Defining the class in the Java programming language to which the
* SQL UDT will be mapped. This class must implement the
* <code>SQLData</code> interface.
* <li>Making an entry in a <code>Connection</code> object's type map
* that contains two things:
* <ul>
* <li>the fully-qualified SQL name of the UDT
* <li>the <code>Class</code> object for the class that implements the
* <code>SQLData</code> interface
* </ul>
* </ol>
* <p>
* When these are in place for a UDT, calling the methods
* <code>ResultSet.getObject</code> or <code>CallableStatement.getObject</code>
* on that UDT will automatically retrieve the custom mapping for it. Also, the
* <code>PreparedStatement.setObject</code> method will automatically map the
* object back to its SQL type to store it in the data source.
*
* <h2>Package Specification</h2>
*
* <ul>
* <li><a href="https://jcp.org/en/jsr/detail?id=221">JDBC 4.3 Specification</a>
* </ul>
*
* <h2>Related Documentation</h2>
*
* <ul>
* <li><a href="http://docs.oracle.com/javase/tutorial/jdbc/basics/index.html">
* Lesson:JDBC Basics(The Javaxx Tutorials > JDBC™ Database Access)</a>
*
* <li>“<i>JDBC™ API Tutorial and Reference, Third Edition</i>”
* </ul>
*/
package java.sql;