Tuesday, May 14, 2013

This is Chapter-4 of Oracle SOA interview questions and answers series.

Question: Types of Adapters ?
Answer: Transactional & Non- Transactional Adapter

Transactional : Database, JMS, AQ, MQ adapters
Non- Transactional: File & FTP adapter

Question: Difference between Read & Sync-Read operation in File & FTP adapter?
Answer: Read is used when Polling is required to be done while SyncRead is used when you need to read the file in between the flow i.e you want to have a synchrnous communication.

Question: What is File Debatching ?
Answer: When a file contains multiple messages, you can choose to publish messages in a specific number of batches. This is referred to as debatching. During debatching, the file reader, on restart, proceeds from where it left off in the previous run, thereby avoiding duplicate messages. File debatching is supported for files in XML and native formats.

Question: What is File ChunkedRead ?
Answer: This is a feature of Oracle File and FTP Adapters that uses an invoke activity within a while loop to process the target file. This feature enables you to process arbitrarily large files.

If an invalid payload is provided, then ChunkedRead scenarios do not throw an exception. When a translation exception (bad record violating the NXSD specification) is encountered, the return header is populated with the translation exception message that includes details such as line and column where the error occurred. All translation errors do not result in a fault. These errors are manifested as a value in the return header. You must check the jca.file.IsMessageRejected and jca.file.RejectionReason header values to ascertain whether an exception has occurred. Additionally, you can also check the jca.file.NoDataFound header value.

Question: Multiple Directories supported in File & FTP adapter ?
Answer: The Oracle File and FTP Adapters support polling multiple directories within a single activation. You can specify multiple directories in JDeveloper as opposed to a single directory. This is applicable to both physical and logical directories.

Question: What is the use of Trigger file ?
Answer: By default, polling by inbound Oracle File and FTP Adapters start as soon as the endpoint is activated. However, if you want more control over polling, then you can use a file-based trigger. Once the Oracle File or FTP Adapter finds the specified trigger file in a local or remote directory, it starts polling for the files in the inbound directory.

For example, a BPEL process is writing files to a directory and a second BPEL process is polling the same directory for files. If you want the second process to start polling the directory only after the first process has written all the files, then you can use a trigger file. You can configure the first process to create a trigger file at the end. The second process starts polling the inbound directory once it finds the trigger file.

Question: Types of Rejection Message Handler ?
  • Web Service Handler
  • Custom Java Handler
  • JMS Queue
  • File

Click here to see more interview question and answer on adapters.

Click here to go to Chapter-3                                                        Click here to go to Chapter-5


  1. i am using db adapter with osb and xml which goes in the biz service has some header elements defined. these header elements are not getting returned in the response xml. pls suggest. in jms que we have correlation id like wise do we have smthng in db adapter

    1. Hi Nishith,

      DB adapter is related to DB tables so I don't think there same header properties you see in db adapter.