For parsing and composing flat files there is a set of counters and related macros available that provide extended features.
Type | Parse | Compose | Description | ID |
---|
automatic counters | | | Eight automatic counters that can be accessed via their IDs AUTO0 .. AUTO7 . | AUTO0 .. AUTO7 |
automatic line counters | | | Two automatic line counters that can be accessed via their IDs LINE0 and LINE1 . | LINE0 , LINE1 |
custom counters | | | Unlimited custom counters that can be accessed via their IDs CUSTOM0 .. CUSTOMx . | CUSTOM0 .. CUSTOMx |
You cannot access these counters directly but only via the macro expressions listed in the table below. Macro expressions referring to one of the counters can be specified on flat file records and on flat file properties (see also Defining a Flat File Data Structure) in the stereotype attributes parseMacro and composeMAcro.
- When parsing/composing the first record, all counters have the initial value of 0.
- Automatic counters automatically increase with each processed record.
- Custom counters have to be increased manually using the IncreaseCounter() macro (see below).
The counters can be handled using the following macros:
Macro | Available on | Available for | Description | Example |
---|
ResetCounter(ID [, Value]) | Record Property | AUTO CUSTOM
| Reset the counter ID to 0 or a given Value. | ResetCounter(AUTO0) ResetCounter(AUTO0, 1) |
IncreaseCounter(ID ) | Record Property | AUTO CUSTOM
| Increases the counter ID by 1. | IncreaseCounter(CUSTOM2) |
GetCounter(ID ) | Property | AUTO LINE CUSTOM
| Read the value of a counter and store it to the current attribute. | GetCounter(LINE0) |
VerifyCounter(ID ) | Property | AUTO LINE CUSTOM
| Compare the value of a counter with the current attribute. This macro will throw an exception if the values are not equal. | VerifyCounter(CUSTOM0) |
Example
The Flat File adapter example shows the usage of an automatic counter to provide a line number to the data records during the composing process. Refer to Defining a Flat File Data Structure for more details on the example flat file.
- Property line stores the number of the product line by using
GetCounter(AUTO0)
. - With every Header record, the counter gets reset to 0 by using
ResetCounter(AUTO0)
. This way the header record will not be counted.
The picture below shows the composing process for the example with emphasis on macro execution.