This article provides an introduction to the array of core new features available in JDBC 4.0.
The java.sql and javax.sql are the primary packages for JDBC 4.0
Auto- loading of JDBC driver class: In JDBC 4 invoking the getConnection() on DriverManager will automatically load a driver. Upon loading the driver, an instance of the driver is created and the registerDriver() method is invoked to make that driver available to clients.
In earlier versions of JDBC, applications had to manually register drivers before requesting Connections. With JDBC 4.0, applications no longer need to issue a Class.forName() on the driver name; instead, the DriverManager will find an appropriate JDBC driver when the application requests a Connection.
SQL exception handling enhancements: JDBC 4 addresses the error handling beautifully. As databases are often remotely accessible resources, problems such as network failures is common and it can cause exceptions when executing a database operation. SQL statements can also cause exceptions. Prior to JDBC 4, most JDBC operations generated a simple SQLException.
SQLXML support: SQLXML is a mapping in the Java programming language for the XML data type in SQL. XML is a built-in type that stores an XML value as a column value in a row of the target table. By default, drivers implement an SQLXML object as a logical pointer to the XML data rather than the data itself. An SQLXML object is valid for the duration of the transaction in which it was created.
Support for RowId data type: JDBC introduces support for ROWID, a data type that had been in use in database products even before it became part of the SQL.
Connection management enhancements: In jdbc it may happen that a Connection is lying idle or not closed in a pool, then it became stale over time. This will led to the connection pool run out of resources due to stale connection. We know that the stale connection doesn't mean that a connection is closed. Now in JDBC 4 Connection class we have provided one method isValid(), which allows a client to query the database driver if a connection is still valid. As database is a shared resource, so many application can access the same data store. To maintain all the records of the client is a difficult task, now in JDBC 4 an application can associate metadata with a database connection via the setClientInfo() method, which takes a name/value pair, or a Properties object.
DataSet implementation of SQL using Annotations: The JDBC 4.0 specification leverages annotations to allow developers to associate a SQL query with a Java class without a need to write a lot of code to achieve this association.
Enhanced BLOB/CLOB functionality
National character set support
Note: This features only available from JDK 1.6 onwards.