Java CAPS 6, Using JCA and JBI, Note 3, Batch Inbound, through Batch Local File to BPEL 2.0
By Michael.Czapski on Jul 18, 2008
Java CAPS 6 has the 5.x compatibility infrastructure which allows one to import 5.x projects right into Java CAPS 6, build, deploy and run without changes. One can also develop repository-based projects in Java CAPS 6 – that’s the 5.x-style projects. This is the old way of developing Java CAPS solutions – still good and valid.
If one were to decide to not use the old way there is the JBI infrastructure, which allows development of solutions that use BPEL Service Engine, XSLT Service Engine, IEP Service Engine, Java EE Service Engine, etc., and a variety of Binding Components. The implication is that business logic is implemented in BPEL 2.0, which is used to orchestrate other services and resources, including interaction with external systems through Binding Components. This is the new way of developing Java CAPS solutions – 100% compatible with the Open Source OpenESB project since it uses the OpenESB project-developed container and components.
Someone might ask “so what happened to eGate?”. “eGate” meaning Java Collaboration Definition-like logic components, eWays and the JMS messaging backbone.
While the facility seems underadvertised/downplayed, Java CAPS 6 provides a number of 5.1 eWay-based JCA Adapters and a moderately easy means of developing JCA Message-Driven Beans that can use these adapters to implement JCD-like logic components and, effectively, eGate-like solutions that do not use BPEL or the JBI infrastructure.
This Note discusses and illustrates the implementation of a mixed Java CAPS 5.x-like integration solution that retrieves a file from the local file system using JCA Adapters and passes its content to a BPEL 2.0 process executing in the JBI container. This requirement I have seen and heard of being implemented in 5.x many times by many customers.
Most of the material in the first 16 pages of this Note is the same as in Note 2.
The JCA Message-Driven Bean, the piece of JCD-like Java logic, will be triggered by a Batch Inbound Adapter (what one would have called the Batch Inbound eWay in 5.1), will read the content of the file using the Batch Local File Adapter (eWay) and will send the payload as a string to a BPEL 2.0 Business Process, which will be triggered by this message and will execute in the JBI container. The batch Inbound Adapter will be configured to use a regular expression to match the name of the file. Once it finds the file it will rename the file by prepending the GUID to the name and will pass the new name, the original name and the directory path to the Java code. This is exactly what the 5.1 Batch Inbound does. The JCA MDB will use the new name, the original name and the directory path to dynamically configure the Batch Local File Adapter to retrieve the file content and rename the file (post transfer) to the original name with some string appended to indicate that the file was processed. This, too, is exactly what one would do in a 5.1 JCD in the same circumstance. Once the payload is available the JCA MDB will use the OneWay WSDL interface and the JBI NMR to send it, as a String, to a BPEL 2.0 process. Both the JCA MDB and the BPEL process will be a part of the same JBI Composite Application and will communicate with one another using the Normalized Message Router (NMR).
The entire Note is available in 03JCA-BInboundThroughBLFToBPEL2.0.pdf