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Java casting exception when trying to use CLOB.createTemporary()

597647Sep 12 2007 — edited Nov 20 2014
I'm having an issue attempting to create a temporary CLOB in Java. When I use a connection from apache's connection pool, I get a casting exception from Java (see below)

java.lang.ClassCastException: org.apache.commons.dbcp.PoolableConnection
at oracle.sql.CLOB.createTemporary(CLOB.java:754)
at oracle.sql.CLOB.createTemporary(CLOB.java:715)

When I make my own connection using DriverManager, I do not have any problems passing the connection object to the createTemporary() method of the oracle.sql.CLOB object.

e.g.

DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
conn = DriverManager.getConnection(url, username,password);

if I use this connection, I can create the temporary clob with no problem. I've attempted to use the following bit of code I have found in other examples to pull off any wrapper that apache may be adding to the connection object:

Connection oracleConnection = conn;

if (conn instanceof org.apache.commons.dbcp.DelegatingConnection) {
// This returns a org.apache.commons.dbcp.PoolableConnection
Connection pc = ((org.apache.commons.dbcp.DelegatingConnection)conn).getDelegate();

// The PoolableConnection is a DelegatingConnection itself - get the delegate (the Oracle connection)
oracleConnection = ((org.apache.commons.dbcp.DelegatingConnection)conn).getDelegate();
}

This still doesn't work. When using the above code, I get the same exception albeit in a different form:

java.lang.ClassCastException: oracle.jdbc.driver.T4CConnection

I saw a posting in this forum about this, but none of the information within seems to help/work:

(857366

If anyone can help shed light on this problem, it would be greatly apprecaited.
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Locked on Dec 9 2008
Added on Sep 12 2007
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