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   9  * by Oracle in the LICENSE file that accompanied this code.
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  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
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  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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  25 
  26 /**
  27  *
  28  * Provides the API for accessing and processing data stored in a
  29  * data source (usually a relational database) using the
  30  * Java™ programming language.
  31  * This API includes a framework whereby different
  32  * drivers can be installed dynamically to access different data sources.
  33  * Although the JDBC™ API is mainly geared
  34  * to passing SQL statements to a database, it provides for reading and
  35  * writing data from any data source with a tabular format.
  36  * The reader/writer facility, available through the
  37  * <code>javax.sql.RowSet</code> group of interfaces, can be customized to
  38  * use and update data from a spread sheet, flat file, or any other tabular
  39  * data source.
  40  *
  41  * <h2>What the JDBC&trade; 4.3 API Includes</h2>
  42  * The JDBC&trade; 4.3 API includes both
  43  * the <code>java.sql</code> package, referred to as the JDBC core API,
  44  * and the <code>javax.sql</code> package, referred to as the JDBC Optional
  45  * Package API. This complete JDBC API
  46  * is included in the Java&trade; Standard Edition (Java SE&trade;), version 7.
  47  * The <code>javax.sql</code> package extends the functionality of the JDBC API
  48  * from a client-side API to a server-side API, and it is an essential part
  49  * of the Java&trade;  Enterprise Edition
  50  * (Java EE&trade;) technology.
  51  *
  52  * <h2>Versions</h2>
  53  * The JDBC 4.3 API incorporates all of the previous JDBC API versions:
  54  * <UL>
  55  *     <LI> The JDBC 4.2 API</li>
  56  *     <LI> The JDBC 4.1 API</li>
  57  *     <LI> The JDBC 4.0 API</li>
  58  *     <LI> The JDBC 3.0 API</li>
  59  *     <LI> The JDBC 2.1 core API</li>
  60  *  <LI> The JDBC 2.0 Optional Package API<br>
  61  *       (Note that the JDBC 2.1 core API and the JDBC 2.0 Optional Package
  62  *       API together are referred to as the JDBC 2.0 API.)</li>
  63  *  <LI> The JDBC 1.2 API</li>
  64  *  <LI> The JDBC 1.0 API</li>
  65  * </UL>
  66  * <P>
  67  * Classes, interfaces, methods, fields, constructors, and exceptions
  68  * have the following "since" tags that indicate when they were introduced
  69  * into the Java platform. When these "since" tags are used in
  70  * Javadoc&trade; comments for the JDBC API,
  71  * they indicate the following:
  72  * <UL>
  73  *     <LI>Since 9 -- new in the JDBC 4.3 API and part of the Java SE platform,
  74  *         version 9</li>
  75  *      <LI>Since 1.8 -- new in the JDBC 4.2 API and part of the Java SE platform,
  76  *         version 8</li>
  77  *  <LI>Since 1.7 -- new in the JDBC 4.1 API and part of the Java SE platform,
  78  *      version 7</li>
  79  * <LI>Since 1.6 -- new in the JDBC 4.0 API and part of the Java SE platform,
  80  *     version 6</li>
  81  *  <LI>Since 1.4 -- new in the JDBC 3.0 API and part of the J2SE platform,
  82  *      version 1.4</li>
  83  *  <LI>Since 1.2 -- new in the JDBC 2.0 API and part of the J2SE platform,
  84  *      version 1.2</li>
  85  *  <LI>Since 1.1 or no "since" tag -- in the original JDBC 1.0 API and part of
  86  *      the JDK&trade;, version 1.1</li>
  87  * </UL>
  88  * <P>
  89  * <b>NOTE:</b> Many of the new features are optional; consequently, there is
  90  * some variation in drivers and the features they support. Always
  91  * check your driver's documentation to see whether it supports a feature before
  92  * you try to use it.
  93  * <P>
  94  * <b>NOTE:</b> The class <code>SQLPermission</code> was added in the
  95  * Java&trade; 2 SDK, Standard Edition,
  96  * version 1.3 release. This class is used to prevent unauthorized
  97  * access to the logging stream associated with the <code>DriverManager</code>,
  98  * which may contain information such as table names, column data, and so on.
  99  *
 100  * <h2>What the <code>java.sql</code> Package Contains</h2>
 101  * The <code>java.sql</code> package contains API for the following:
 102  * <UL>
 103  *   <LI>Making a connection with a database via the <code>DriverManager</code> facility
 104  *   <UL>
 105  *       <LI><code>DriverManager</code> class -- makes a connection with a driver
 106  *       <LI><code>SQLPermission</code> class -- provides permission when code
 107  *                   running within a Security Manager, such as an applet,
 108  *                   attempts to set up a logging stream through the
 109  *                   <code>DriverManager</code>
 110  *       <LI><code>Driver</code> interface -- provides the API for registering
 111  *              and connecting drivers based on JDBC technology ("JDBC drivers");
 112  *              generally used only by the <code>DriverManager</code> class
 113  *       <LI><code>DriverPropertyInfo</code> class -- provides properties for a
 114  *              JDBC driver; not used by the general user
 115  *   </UL>
 116  *   <LI>Sending SQL statements to a database
 117  *   <UL>
 118  *       <LI><code>Statement</code> --  used to send basic SQL statements
 119  *       <LI><code>PreparedStatement</code> --  used to send prepared statements or
 120  *               basic SQL statements (derived from <code>Statement</code>)
 121  *       <LI><code>CallableStatement</code> --  used to call database stored
 122  *               procedures (derived from <code>PreparedStatement</code>)
 123  *       <LI><code>Connection</code> interface --  provides methods for creating
 124  *              statements and managing connections and their properties
 125  *       <LI><code>Savepoint</code> --  provides savepoints in a transaction
 126  *
 127  *   </UL>
 128  *   <LI>Retrieving and updating the results of a query
 129  *   <UL>
 130  *       <LI><code>ResultSet</code> interface
 131  *   </UL>
 132  *   <LI>Standard mappings for SQL types to classes and interfaces in the
 133  *       Java programming language
 134  *   <UL>
 135  *       <LI><code>Array</code> interface -- mapping for SQL <code>ARRAY</code>
 136  *       <LI><code>Blob</code> interface -- mapping for SQL <code>BLOB</code>
 137  *       <LI><code>Clob</code> interface -- mapping for SQL <code>CLOB</code>
 138  *       <LI><code>Date</code> class -- mapping for SQL <code>DATE</code>
 139  *        <LI><code>NClob</code> interface -- mapping for SQL <code>NCLOB</code>
 140  *       <LI><code>Ref</code> interface -- mapping for SQL <code>REF</code>
 141  *        <LI><code>RowId</code> interface -- mapping for SQL <code>ROWID</code>
 142  *       <LI><code>Struct</code> interface -- mapping for SQL <code>STRUCT</code>
 143  *        <LI><code>SQLXML</code> interface -- mapping for SQL <code>XML</code>
 144  *       <LI><code>Time</code> class -- mapping for SQL <code>TIME</code>
 145  *       <LI><code>Timestamp</code> class -- mapping for SQL <code>TIMESTAMP</code>
 146  *       <LI><code>Types</code> class -- provides constants for SQL types
 147  *   </UL>
 148  *   <LI>Custom mapping an SQL user-defined type (UDT) to a class in the
 149  *        Java programming language
 150  *   <UL>
 151  *       <LI><code>SQLData</code> interface -- specifies the mapping of
 152  *               a UDT to an instance of this class
 153  *       <LI><code>SQLInput</code> interface -- provides methods for reading
 154  *               UDT attributes from a stream
 155  *       <LI><code>SQLOutput</code> interface -- provides methods for writing
 156  *               UDT attributes back to a stream
 157  *   </UL>
 158  *   <LI>Metadata
 159  *   <UL>
 160  *       <LI><code>DatabaseMetaData</code> interface -- provides information
 161  *               about the database
 162  *       <LI><code>ResultSetMetaData</code> interface -- provides information
 163  *               about the columns of a <code>ResultSet</code> object
 164  *       <LI><code>ParameterMetaData</code> interface -- provides information
 165  *               about the parameters to <code>PreparedStatement</code> commands
 166  *   </UL>
 167  *   <LI>Exceptions
 168  *      <UL>
 169  *        <LI><code>SQLException</code> -- thrown by most methods when there
 170  *               is a problem accessing data and by some methods for other reasons
 171  *        <LI><code>SQLWarning</code> -- thrown to indicate a warning
 172  *        <LI><code>DataTruncation</code> -- thrown to indicate that data may have
 173  *                been truncated
 174  *        <LI><code>BatchUpdateException</code> -- thrown to indicate that not all
 175  *               commands in a batch update executed successfully
 176  *      </UL>
 177  * </UL>
 178  *
 179  *     <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.3 API</h3>
 180  * <UL>
 181  *     <LI>Added <code>Sharding</code> support</LI>
 182  *     <LI>Enhanced <code>Connection</code> to be able to provide hints
 183  *         to the driver that a request, an independent unit of work,
 184  *         is beginning or ending</LI>
 185  *     <LI>Enhanced <code>DatabaseMetaData</code> to determine if Sharding is
 186  *     supported</LI>
 187  *     <LI>Added the method <code>drivers</code> to <code>DriverManager</code>
 188  *             to return a Stream of the currently loaded and
 189  *             available JDBC drivers</LI>
 190  *     <LI>Added support to <code>Statement</code> for enquoting literals
 191  *     and simple identifiers</LI>
 192  *     <LI>Clarified the Java SE version that methods were deprecated</LI>
 193  * </UL>
 194  *
 195  *     <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.2 API</h3>
 196  * <UL>
 197  *     <LI>Added <code>JDBCType</code>  enum and <code>SQLType</code> interface</li>
 198  *     <LI>Support for <code>REF CURSORS</code> in <code>CallableStatement</code>
 199  *     </LI>
 200  *     <LI><code>DatabaseMetaData</code> methods to return maximum Logical LOB size
 201  *         and if Ref Cursors are supported</LI>
 202  *     <LI>Added support for large update counts</LI>
 203  *
 204  * </UL>
 205  *
 206  *     <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.1 API</h3>
 207  * <UL>
 208  *     <LI>Allow <code>Connection</code>,
 209  *         <code>ResultSet</code> and <code>Statement</code> objects to be
 210  *         used with the try-with-resources statement</LI>
 211  *     <LI>Support added to <code>CallableStatement</code> and
 212  *         <code>ResultSet</code> to specify the Java type to convert to via the
 213  *         <code>getObject</code> method</LI>
 214  *     <LI><code>DatabaseMetaData</code> methods to return PseudoColumns and if a
 215  *         generated key is always returned</LI>
 216  *     <LI>Added support to <code>Connection</code> to specify a database schema,
 217  *     abort and timeout a physical connection.</LI>
 218  *     <LI>Added support to close a <code>Statement</code> object when its dependent
 219  *     objects have been closed</LI>
 220  *     <LI>Support for obtaining the parent logger for a <code>Driver</code>,
 221  *      <code>DataSource</code>, <code>ConnectionPoolDataSource</code> and
 222  *      <code>XADataSource</code></LI>
 223  *
 224  * </UL>
 225  * <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.0 API</h3>
 226  * <UL>
 227  *   <LI>auto java.sql.Driver discovery -- no longer need to load a
 228  * <code>java.sql.Driver</code> class via <code>Class.forName</code>
 229  *  <LI>National Character Set support added
 230  *  <li>Support added for the SQL:2003 XML data type
 231  *  <lI>SQLException enhancements -- Added support for cause chaining; New SQLExceptions
 232  *  added for common SQLState class value codes
 233  *  <li>Enhanced Blob/Clob functionality -- Support provided to create and free a Blob/Clob instance
 234  *  as well as additional methods added to improve accessibility
 235  *  <li>Support added for accessing a SQL ROWID
 236  *  <li>Support added to allow a JDBC application to access an instance of a JDBC resource
 237  *  that has been wrapped by a vendor, usually in an application server or connection
 238  *  pooling environment.
 239  *  <li>Availability to be notified when a <code>PreparedStatement</code> that is associated
 240  *  with a <code>PooledConnection</code> has been closed or the driver determines is invalid
 241  *
 242  *
 243  * </UL>
 244  *
 245  *
 246  * <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 3.0 API</h3>
 247  * <UL>
 248  *   <LI>Pooled statements -- reuse of statements associated with a pooled
 249  *        connection
 250  *   <LI>Savepoints -- allow a transaction to be rolled back to a designated
 251  *       savepoint
 252  *   <LI>Properties defined for <code>ConnectionPoolDataSource</code> -- specify
 253  *       how connections are to be pooled
 254  *   <LI>Metadata for parameters of a <code>PreparedStatement</code> object
 255  *   <LI>Ability to retrieve values from automatically generated columns
 256  *   <LI>Ability to have multiple <code>ResultSet</code> objects
 257  *        returned from <code>CallableStatement</code> objects open at the
 258  *       same time
 259  *   <LI>Ability to identify parameters to <code>CallableStatement</code>
 260  *       objects by name as well as by index
 261  *   <LI><code>ResultSet</code> holdability -- ability to specify whether cursors
 262  *       should be held open or closed at the end of a transaction
 263  *   <LI>Ability to retrieve and update the SQL structured type instance that a
 264  *       <code>Ref</code> object references
 265  *   <LI>Ability to programmatically update <code>BLOB</code>,
 266  *       <code>CLOB</code>, <code>ARRAY</code>, and <code>REF</code> values.
 267  *   <LI>Addition of the <code>java.sql.Types.DATALINK</code> data type --
 268  *       allows JDBC drivers access to objects stored outside a data source
 269  *   <LI>Addition of metadata for retrieving SQL type hierarchies
 270  * </UL>
 271  *
 272  * <h3><code>java.sql</code> Features Introduced in the JDBC 2.1 Core API</h3>
 273  * <UL>
 274  *   <LI>Scrollable result sets--using new methods in the <code>ResultSet</code>
 275  *        interface that allow the cursor to be moved to a particular row or to a
 276  *        position relative to its current position
 277  *   <LI>Batch updates
 278  *   <LI>Programmatic updates--using <code>ResultSet</code> updater methods
 279  *   <LI>New data types--interfaces mapping the SQL3 data types
 280  *   <LI>Custom mapping of user-defined types (UDTs)
 281  *   <LI>Miscellaneous features, including performance hints, the use of character
 282  *        streams, full precision for <code>java.math.BigDecimal</code> values,
 283  *        additional security, and
 284  *        support for time zones in date, time, and timestamp values.
 285  * </UL>
 286  *
 287  * <h3><code>javax.sql</code> Features Introduced in the JDBC 2.0 Optional
 288  * Package API</h3>
 289  * <UL>
 290  *   <LI>The <code>DataSource</code> interface as a means of making a connection.  The
 291  *       Java Naming and Directory Interface&trade;
 292  *       (JNDI) is used for registering a <code>DataSource</code> object with a
 293  *       naming service and also for  retrieving it.
 294  *   <LI>Pooled connections -- allowing connections to be used and reused
 295  *   <LI>Distributed transactions -- allowing a transaction to span diverse
 296  *       DBMS servers
 297  *   <LI><code>RowSet</code> technology -- providing a convenient means of
 298  *        handling and passing data
 299  * </UL>
 300  *
 301  *
 302  * <h3>Custom Mapping of UDTs</h3>
 303  * A user-defined type (UDT) defined in SQL can be mapped to a class in the Java
 304  * programming language. An SQL structured type or an SQL <code>DISTINCT</code>
 305  * type are the UDTs that may be custom mapped.  The following three
 306  * steps set up a custom mapping:
 307  * <ol>
 308  *   <li>Defining the SQL structured type or <code>DISTINCT</code> type in SQL
 309  *   <li>Defining the class in the Java programming language to which the
 310  *        SQL UDT will be mapped.  This class must implement the
 311  *        <code>SQLData</code> interface.
 312  *   <li>Making an entry in a <code>Connection</code> object's type map
 313  *       that contains two things:
 314  *    <ul>
 315  *        <li>the fully-qualified SQL name of the UDT
 316  *        <li>the <code>Class</code> object for the class that implements the
 317  *            <code>SQLData</code> interface
 318  *    </ul>
 319  * </ol>
 320  * <p>
 321  * When these are in place for a UDT, calling the methods
 322  * <code>ResultSet.getObject</code> or <code>CallableStatement.getObject</code>
 323  * on that UDT will automatically retrieve the custom mapping for it. Also, the
 324  * <code>PreparedStatement.setObject</code> method will automatically map the
 325  * object back to its SQL type to store it in the data source.
 326  *
 327  * <h2>Package Specification</h2>
 328  *
 329  * <ul>
 330  *   <li><a href="https://jcp.org/en/jsr/detail?id=221">JDBC 4.3 Specification</a>
 331  * </ul>
 332  *
 333  * <h2>Related Documentation</h2>
 334  *
 335  * <ul>
 336  *   <li><a href="http://docs.oracle.com/javase/tutorial/jdbc/basics/index.html">
 337  *           Lesson:JDBC Basics(The Javaxx Tutorials &gt; JDBC&trade; Database Access)</a>
 338  *
 339  *  <li><a href="http://www.oracle.com/technetwork/java/index-142838.html">
 340  *           <i>JDBC&trade; API Tutorial and Reference, Third Edition</i></a>
 341  * </ul>
 342  */
 343 package java.sql;