IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

230 IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

boolean convEnded; (Output)

boolean asyncOutputAvailable; (Output)

New properties and property values can be added to support additional function in later

releases of IMS Connector for Java. The IMSInteractionSpec object has getter and setter

methods for all properties. We explain these properties later.

Input record

IMS Connector for Java views the JCA input record as a Java byte array, in a well-defined

encoding and containing the fields of the IMS transaction input message in the right order, at

the correct offset, with the required length, and aligned as expected by the IMS application

program that is invoked. In JCA, this byte array has to be a Java object that implements two

CCI interfaces:

 javax.resource.cci.Record

 javax.resource.cci.Streamable

This record can be built using the tooling wizards of an integrated development environment

such as WebSphere Studio Application Developer Integration Edition or Rational Application

Developer, or your Java application can build the input record without using tooling.

Output record

The output record implements the same CCI interfaces as the input record. For some IMS

transactions, there are additional considerations for the output record. An IMS application

program can return one of a number of possible output messages. An IMS application

program can also return a variable length output message. Variable length output messages

include multiple segment output messages and output messages containing arrays with a

variable number of elements. In these cases, the Java application must include special logic

to process the output message. This logic is illustrated in samples provided by IMS

Connector for Java. You can find the samples at the following Web page:

http://www.ibm.com/software/data/ims/examples/exHome.html

12.2.5 Security

The JCA security contract uses the Java Authentication and Authorization Service (JAAS)

Subject class to provide security information. When a new ManagedConnection is created,

the createManagedConnection() method is passed a Subject instance. The connection uses

the Subject when it attempts to sign on to the EIS. A Subject contains information about the

principal, or name, of the Subject, along with information about the security credentials held

by the principal.

JCA v1.0 defines two types of credentials:

 A GenericCredential is a Java wrapper, representing a specific security mechanism, such

as a Kerberos credential.

 A PasswordCredential holds user name and password information.

An application server supporting JCA v1.0 must provide implementations of both of these

interfaces. In JCA v1.5, the GenericCredential interface has been deprecated but is still

usable. The recommended replacement interface, the org.ietf.jgss.GSSCredentialinterface in

J2SE™ v1.4, is not yet fully supported by WebSphere Application Server for z/OS nor by IMS

Connector for Java. As a result, the GenericCredential interface continues to be used by

WebSphere Application Server for z/OS and IMS Connector for Java.