25.6 Accessing the Current Database Transaction

Since the ADF Business Components components abstract all of the lower-level database programming details for you, you typically won't need direct access to the JDBC Connection object. Unless you use the reserved release mode described in Section 28.3.1, "Supported Release Levels", there is no guarantee at runtime that your application will use the exact same application module instance or JDBC Connection instance across different web page requests. Since inadvertently holding a reference to the JDBC Connection object in this type of pooled services environment can cause unpredictable behavior at runtime, by design, the ADF Business Components layer has no direct API to obtain the JDBC Connection. This is an intentional attempt to discourage its direct use and inadvertent abuse.

However, on occasion it may come in handy when you're trying to integrate third-party code with ADF Business Components, so you can use a helper method like the one shown in Example 25-10 to access the connection.

Example 25-10 Helper Method to Access the Current JDBC Connection

/**
 * Put this method in your XXXXImpl.java class where you need
 * to access the current JDBC connection
 */
private Connection getCurrentConnection() throws SQLException {
 /* Note that we never execute this statement, so no commit really happens */
 PreparedStatement st = getDBTransaction().createPreparedStatement("commit",1);
 Connection conn = st.getConnection();
 st.close();
 return conn;
}

Caution: Oracle recommends that you never cache the JDBC connection obtained using the helper method above in your own code anywhere. Instead, call the helper method each time you need it to avoid inadvertently holding a reference to a JDBC Connection that might be used in another request by another user at a later time do to the pooled services nature of the ADF runtime environment.