I highly recommend the use of JDeveloper as the IDE for Oracle Application Server (Oracle 9iAS and Oracle10gAS — or however they are spelling/selling it these days). As I understand it, JDeveloper is now offered as a free IDE by Oracle for developers. With the built in integration for OracleAS for deploying Java-based web applications, portlets, ADF (Oracle’s implementation on top of the hot JSF techology), and much more, JDeveloper is quickly becoming the free, non-open source IDE of choice for the enterprise. ADF, specifically, requires a license before deployment to production, but regardless of this, JDeveloper has much to offer and what seems to be a solid roadmap of features planned by Oracle.