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Oracle® Database JDBC Developer's Guide and Reference
10g Release 2 (10.2)

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12 Proxy Authentication

Oracle Java Database Connectivity (JDBC) provides proxy authentication, also called N-tier authentication. This feature is supported through both the JDBC Oracle Call Interface (OCI) driver and the JDBC Thin driver. This chapter contains the following sections:

Need for Proxy Authentication

Proxy authentication allows one JDBC connection to act as a proxy for other JDBC connections. An application may need proxy authentication for any of the following reasons:


In this chapter, a JDBC connection to a database is a user session in the database and vice versa.

Creating Proxy Connections

In order to get a proxy connection, a user, say jeff, has to connect to the database through another user, say scott. The proxy user, scott, should have an active authenticated connection. Using this active connection, the driver sends issues a command to the server to create a session for the user, jeff. The server returns the new session id, and the driver sends a session switch command to switch to this new session.

You can create proxy connections using any one of the following options:

The JDBC OCI and Thin driver switch sessions in the same manner. The drivers permanently switch to the new session, jeff. As a result, the proxy session, scott, is not available until the new session, jeff, is closed.


  • All the options can be associated with roles.

  • When opening a new proxied connection, a new session is started on the database server. Along with this session a new local transaction is created.

Caching Proxy Connections

Proxy connections, like normal connections, can be cached. Caching proxy connections enhances the performance. To create a proxy connection, you need to first create a connection using one of the getConnection methods on a cache enabled OracleDataSource object. A proxy session is then created by calling the openProxySession method on the obtained connection.

When the close(PROXY_CONNECTION) method is called on this physical connection, the proxy session created on this connection gets closed. This is similar to closing a proxy session on a non-cached connection. The standard close method must be called explicitly to close the connection itself. If the close method is called directly, without closing the proxy session, then both the proxy session and the connection are closed.

A proxy connection may be cached in the connection cache using the connection attributes feature of the connection cache. Connection attributes are name/value pairs that are user-defined and help tag a connection before returning it to the connection cache for reuse. When the tagged connection is retrieved, it can be directly used without having to do a round trip to create or close a proxy session. Implicit connection cache supports caching of any user/password authenticated connection. Therefore, any user authenticated proxy connection can be cached and retrieved.

A sample code illustrating the use of proxy sessions is as follows:

java.util.Properties connAttr = null;
//obtain connection from a cache enabled DataSource
OracleConnection conn = ds.getConnection("scott",tiger");
conn.openProxySession(proxyType, proxyProps);
conn.applyConnectionAttributes(connAttr); //apply attributes to the connection
conn.close(); //return the tagged connection to the cache
//come back later and ask for Joe's proxy connection
conn=ds.getConnection(connAttr); //This will retrieve Joe's proxy connection

It is recommended that proxy connections should not be closed without applying the connection attributes. If a proxy connection is closed without applying the connection attributes, the connection is returned to the connection cache for reuse, but cannot be retrieved. The connection caching mechanism does not remember or reset session state.

A proxy connection can be removed from the connection cache by closing the connection directly. This can be done by calling the close(INVALID_CONNECTION) method on the connection. The method closes both the connection and the proxy session and removes them from the cache.