Defining a Flat File

Defining the Flat File

The flat file structure is defined in a class diagram. A root class defines the file and its settings (like e.g. the record separator). This class must have stereotype <<FlatFile>>.

As this is the root of a flat file declaration no attributes are allowed. You should give this class a meaningful name, because the output object flow of the <<FlatFileAdapter>> action in the activity diagram uses this class as a type.

You can change the flat file settings on the specification dialog of the root class.

Figure: Change Flat File Settings

Value <NewLine> of tag Record Separator is a literal placeholder for special character \n. A complete list of all placeholders is listed below.

The other optional tagged values are listed below.

Flat File Settings

Find below a list of all tagged values corresponding to stereotype <<FlatFile>>.

Defining a Flat File Record

The record structure and the relation between records is defined by one or more child classes and the association to their parent class (e.g. the root class or a parent record class). All records have stereotype <<FlatFileRecord>>.

Figure: Flat File Record Structure

Flat File Record Groups

Additionally, (virtual) groups can be defined by stereotype <<FlatFileGroup>>. These classes have no physical representation in the flat file itself.

Flat File Record Settings

Find below a list of all tagged values corresponding to the stereotype <<FlatFileRecord>>.

For detailed information on associations see Defining a Flat File or Defining a Flat File .

Flat File Group Settings

You can group multiple records in one virtual structure by using the stereotype <<FlatFileGroup>>. This virtual group does not have a representation in the flat file and therefore cannot hold any attributes. Apart from this, this element has the same behavior like a flat file record. For parsing and composing, the pattern and conditions are checked but no mapping takes place. The record details are given to the associated class where the mapping is done.

Find below a list of all tagged values corresponding to the stereotype  <<FlatFileGroup>> .

Associations Endings of <<FlatFileRecord>> and <<FlatFileGroup>>

All associations ending on a class with stereotype <<FlatFileRecord>> or <<FlatFileGroup>> can have additional attributes, if the association end has stereotype <<FlatFileSubRecord>> applied.

Find below a list of all tagged values corresponding to stereotype    <<FlatFileSubRecord>> .

Defining Flat File Record Attributes

All Attributes on a <<Flat File Record>> class need to have stereotype <<FlatFileAttribute>>. Depending on the layout type of the flat file (fixed or separated), you can specify different tagged values (see Defining a Flat File and Defining a Flat File). Additionally, you can define record fields as to be of complex type (see Defining a Flat File).

Attribute Settings for attributeLayout = fixed

For flat files having a fixed layout, you need to specify external length and order of the attribute, and optionally, you can specify a padding.

Attribute Settings for attributeLayout = separated

For attributes in separated flat files, you can supply an offset to specify the position of the field (attribute) in respect of the other record fields.

Complex Flat File Record Attributes

Flat file record attributes can by of complex type. The complex type must have stereotype <<FlatFileComplexAttribute>> applied, then.

Figure: Flat File Complex Attribute

You can use this class to divide a record field into sub-fields. You can think of this like a <<FlatFileRecord>> placed within a single field. Most of the tagged values that are valid for a flat file record are valid for a complex attribute, too. Though, the scope of these settings is not the record, but the field.

Macro Expressions

Available macros are counters:

• eight automatic counters with ID AUTO0 .. AUTO7 (for parsing and composing)

• two automatic line counters with ID LINE0 and LINE1 (for parsing only)

• unlimited custom counters with ID CUSTOM0 .. CUSTOMx (for parsing and composing).

Automatic counters automatically increase with each processed record, whereas custom counters have to be increased manually using the IncreaseCounter() macro. When parsing/composing the first record, all counters have the initial value of 0.

For GetCounter() and VerifyCounter() only attributes of type Integer are supported.