JDBC 4 is currently in Early Draft Review in the JCP (JSR 221). The proposed spec focuses on ease-of-use and programmer productivity, and defines support for SQL 2003 data types, including SQL's native XML type. A new Artima article
describes the most important new features.
While prior JDBC versions focused on incremental improvements providing functionality to J2EE application servers, JDBC 4's key priority is to make it easier for developers to work directly with the JDBC API. Much of JDBC 4's ease-of-development features are a direct result of new capabilities available in J2SE 1.5.
JDBC 4 also introduces several SQL 2003 features, including a Java-specific mapping for the new XML SQL type, support for national character sets, and exposes to tools more information about the state of database connections and statements.