Channel and container examples

Containers are named blocks of data designed for passing information between programs. Containers are grouped in sets called channels, which act as the interface between programs. Channels and containers offer the advantage that more than 32KB of data can be passed, and both character and binary data can be specified. Character data (or strings in Java terms) is automatically converted at the API level, whereas binary data (or a byte array in Java terms) is flowed unconverted. By contrast, COMMAREAs are confined to a 32KB limit and are unstructured byte arrays. Multiple containers can be passed between programs within a channel, providing a high degree of flexibility about how to structure data.

For introductory information about channels and containers, and guidance about using channels in non-Java applications, see Transferring data between programs using channels. For information about tools that allow Java™ programs to access existing CICS application data, see Interacting with structured data from Java.

JCICS API mapping to EXEC CICS API lists the classes and methods that implement JCICS support for channels and containers.

The CICS condition CHANNELERR results in a ChannelErrorException being thrown; the CONTAINERERR CICS condition results in a ContainerErrorException ; the CCSIDERR CICS condition results in a CCSIDErrorException.