Using the Catalogs tab
The Catalogs tab displays catalogs of block templates that are available for use in a scenario. A catalog of block templates is a folder that contains one or more .bdf files, each defining a block template that the user can instantiate in a scenario. A catalog of block templates can also contain subfolders that themselves contain .bdf files. This hierarchical organization of a catalog appears when it is displayed in the Catalogs tab.
This text uses the term block template to refer to a block's definition on disk (within a .bdf file), whereas block is used to refer to an instance of a block template that has been added to the scenario.
The format and structure of a
.bdf file is discussed in
File Definition Formats.
Typically, you might want to use multiple block template catalogs to distinguish between block templates supplied by Apama, block templates that you have developed yourself, and block templates that you have obtained from third parties.
In addition, within each block template catalog, as the number of block templates available to a scenario author could be very large it is useful to organize them into categories that reflect their functionality. Furthermore, as the block templates available are enhanced and new versions released, one is likely to need access to multiple versions of the same block templates.
A block template catalog's folder structure is therefore as follows:
A root folder that represents the block template catalog, and within it,
One or more sub-folders that represent functional categories of block templates, and within each,
A folder called
block_template_name.bdf, which contains
The different available versions of a block template in distinct
.bdf files.
The default block template catalog is simply called blocks. In the Catalogs tab, it appears as Standard Blocks.
