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Jaguar is the component transaction engine of Enterprise Application Server and provides an environment for deploying the middle-tier logic of distributed component-based applications. It is no longer sold as a separate product and it is part of Enterprise Application Studio.
The following describes the silent features of Jaguar and what you can do with them:
Connection caching is similar to the transaction pooling in PowerBuilder. Connection caching allows Jaguar components to share pools of pre-allocated connections to a remote database server, avoiding the overhead imposed when each instance of a component creates a separate connection. Connection caching gives one more level of control in using the cached connection over the transaction pooling. In Connection caching, you can specify whether to reuse the connection when the connection cache name matches or the parameters in the connection cache matches. In transaction pooling, only the later option is available.
A Jaguar transaction is a transaction whose boundaries and outcome are determined by Jaguar. You can mark components to indicate that they will provide transaction support. When a component provides transaction support, Jaguar ensures that the component's database operations execute as part of a transaction. Multiple Jaguar components can participate in a single Jaguar transaction; Jaguar ensures that database changes performed by the participating components either all are committed or rolled back. With few mouse clicks, you can mark a PowerBuilder class object deployed as Jaguar component to participate in Jaguar transactions.
Instance pooling allows Jaguar clients to reuse component instances. It eliminates the overhead of repeated creation and destruction of component instances. This improves the overall performance of a Jaguar server.
Jaguar CTS allows multiple clients to share the same component instance. Conceptually, even though PowerBuilder shared objects and Jaguar shared components are the same, they are different. While deploying the PowerBuilder class objects you have the option to mark them as shared component.
Sybase fully integrated both PowerBuilder and Jaguar by hosting the PowerBuilder virtual machine natively in Jaguar. Jaguar can communicate directly with PowerBuilder non-visual user objects and vice versa. You can leverage your PowerBuilder skills and develop Jaguar components in PowerBuilder using PowerScript and deploy them in Jaguar. At the same time, you can take advantage of the high-performance built-in transaction server in Jaguar. It takes care of efficient management client sessions, security, threads, third-tier database connections, and transaction flow. Unlike Distributed PowerBuilder server applications you develop, you will not need to write code to implement these services. On top of that, PowerBuilder version 7.0 has a lot wizards that creates the necessary PowerBuilder object to help you in migrating your Distributed PowerBuilder applications to Jaguar CTS.
A PowerBuilder application can act as a client to a Jaguar server. In addition, a Jaguar server can contain PowerBuilder custom class user (non-visual) objects that execute as middle-tier components. To take advantage of those built-in services, you may want to migrate your Distributed PowerBuilder Applications to Jaguar CTS. That is exactly Sybase wants you to do, that�s why they did not add any new functionality to DPB side.
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