CWF properties for element reference and local element binary types

The Custom Wire Format properties described here apply to:

Physical representation

Property Type Meaning
Length Count Button and Integer If you have set Length Type to Count, enter the number of length units for the element.

The minimum value that you can specify is 1.

The maximum value that you can specify is 2147483647.

The default value is empty (not set).

Length Reference Button and Enumerated type If you have selected the length to be defined by Length Reference, select the name of the Integer object that specifies the length of this object. Make your selection from the drop-down list of Integer objects that are defined as siblings of the current object, and occur before it in the structure of the message.

For information about reordering elements, see Reordering objects.

Length Units Enumerated type Subject to the Physical Type that has been set, select one of the following from the drop-down list:
  • Bytes. This specifies that X bytes are processed where X is the value of Length Count, or of the INTEGER specified in Length Reference.
  • Characters. The meaning of this option depends on the value that you have set in the message's CCSID or that you have set for the message set property Default CCSID.
    • If you have specified an SBCS CCSID, X bytes are processed where X is the value of Length Count or of the INTEGER specified by Length Reference.
    • If you have specified a DBCS CCSID, Y bytes are processed, where Y is the value of Length Count or of the INTEGER specified in Length Reference multiplied by two.
    • If you have specified an MBCS CCSID, the parser reads 1 character at a time and determines whether the character comprises 1 or more bytes. The parser performs Z reads, where Z is the value of Length Count or of the INTEGER specified in Length Reference.
  • Character Units. This specifies that the size of character unit is determined by the value that you have set in the message's CCSID, or for the message set property Default CCSID. The number of bytes processed is the size of character unit multiplied by the value of Length Count, or of the INTEGER specified in Length Reference.
  • End of Bitstream. All data until end of bit stream is processed. This option is valid only if the element is the last in the message. If you select this value, you do not need to enter a value in Length Count or Length Reference.

The default is bytes.

Byte alignment

Property Type Meaning
Byte Alignment Enumerated type Specify how the object is aligned from the start of the message. Select one of:
  • 1 Bytes. This is the default value.
  • 2 Bytes
  • 4 Bytes
  • 8 Bytes
  • 16 Bytes
Leading Skip Count Integer Specify the number of bytes to skip before reading or writing this object. The default is 0, the minimum value is 0, and the maximum value is 999999. You can use this value to ignore unwanted fields in a structure, or to model a field defined by C or COBOL data which requires alignment on a 2, 4, 8 or 16 byte boundary. Specify the number of bytes to skip before reading or writing this object. When an output message is written, Skip Count bytes are assigned the value of the message set Byte Alignment Pad property.

For repeating objects, this property is applied to the first instance only.

Trailing Skip Count Integer Specify the number of bytes to skip after reading or writing this object. The default is 0, the minimum value is 0, and the maximum value is 999999. You can use this value to ignore unwanted fields in a structure, or to model a repeating structure containing fields which require alignment on a 2, 4, 8 or 16 byte boundary. When an output message is written, Skip Count bytes are assigned the value of the message set Byte Alignment Pad property.

For repeating objects, this property is applied to all instances.

Repeat

Property Type Meaning
Repeat Reference Enumerated type Use this property if the object occurs multiple times, and the number of occurrences is given dynamically by a field earlier in the message.

Select an integer object from the drop-down list of integer objects that occur before this object in the structure of the message. The value of the selected integer specifies the number of occurrences of this object. If no objects are listed, there are no integer objects prior to this one in the message structure.

If a Repeat Reference is specified, it overrides any setting for the Max Occurs logical property when parsing and writing the message, but not for validation of the message.

Related concepts
Message modeling
The message model
Custom wire format: relationship to the logical model
Related tasks
Developing message models
Working with message model objects
Related reference
Message model reference information
Message model object properties
Logical properties for message model objects
Custom Wire Format physical properties for message model objects
XML wire format physical properties for message model objects
TDS format physical properties for message model objects
Documentation properties for all message set objects
Message model object properties by object
Additional MRM domain information