PTDiffusionRecordV2Model Class Reference

Introduction

A data model based upon a schema.

A read only model can be created from any PTDiffusionRecordV2 object using the PTDiffusionRecordV2::modelWithSchema: method. The model then provides direct access to the fields within the data. Fields may be accessed either by explicitly specifying the record and field occurrence or by specifying a key of the form:

recordName(recordIndex).fieldName(fieldIndex)

Indexes start from 0 and if omitted then 0 is assumed. The record name may also be omitted, in which case the first record definition. This form of addressing is useful when there is only one record definition.

Examples of valid keys include:

Key	Meaning
Address(4).AddressLine(3)	The 4th AddressLine occurrence within the 5th Address record.
Address.Name	The first (or only) Name field within the first (or only) Address record.
AddressLine(1)	The 2nd AddressLine field within the first (or only) record.
Name	The first (or only) Name field within the first (or only) record.

The recordCountWithRecordName:error: (PTDiffusionRecordV2Model) and fieldCountWithRecordName:recordIndex:fieldName:error: (PTDiffusionRecordV2Model) methods are useful for determining the actual number of occurrences of variable multiplicity items.

Since

6.0

Inheritance diagram for PTDiffusionRecordV2Model:

Instance Methods
(nullable PTDiffusionRecordV2 *)	- valueWithError:
(nullable NSNumber *)	- fieldCountWithRecordName:recordIndex:fieldName:error:
(nullable NSNumber *)	- recordCountWithRecordName:error:
(nullable NSString *)	- fieldValueForKey:error:
(nullable NSString *)	- fieldValueForRecordName:recordIndex:fieldName:fieldIndex:error:

Method Documentation

fieldCountWithRecordName:recordIndex:fieldName:error:

- (nullable NSNumber *) fieldCountWithRecordName:		(NSString *)	recordName
recordIndex:		(SInt32)	recordIndex
fieldName:		(NSString *)	fieldName
error:		(NSError **)	error

Returns the actual number of occurrences of a named field within a specified record occurrence.

For all but variable fields this returns the schema defined number of occurrences of the field.

Parameters

recordName	The record name.
recordIndex	The record index.
fieldName	The field name.
error	If this method returns nil to indicate that an error occurred then this will be populated with the reason for that failure.

Returns

The actual number of occurrences of the field as an unsigned integer; or nil if an error occurred, in which case *error will be populated with the failure reason. Reasons for failure include:

• either recordName or fieldName are not defined in the schema.
• recordIndex is out of bounds.

Exceptions

NSInvalidArgumentException

If either recordName or fieldName is nil, or if recordIndex is negative.

Since

6.0

fieldValueForKey:error:

- (nullable NSString *) fieldValueForKey:		(NSString *)	key
error:		(NSError **)	error

Get a field value.

This allows an item to be addressed using a key of the form recordName(recordIndex).fieldName(fieldIndex). Indexes may be omitted in which case 0 is assumed. The record part may also be omitted in which case the first occurrence of the first record is assumed.

Parameters

key	The field key.
error	If this method returns nil to indicate that an error occurred then this will be populated with the reason for that failure.

Returns

The field value; or nil if an error occurred, in which case *error will be populated with the failure reason. Reasons for failure include:

• the key does not address a valid field.
• an index is out of bounds.
• the key format is invalid.
• an index is not a valid number.

Exceptions

NSInvalidArgumentException

If key is `nil`.

Since

6.0

fieldValueForRecordName:recordIndex:fieldName:fieldIndex:error:

- (nullable NSString *) fieldValueForRecordName:		(NSString *)	recordName
recordIndex:		(SInt32)	recordIndex
fieldName:		(NSString *)	fieldName
fieldIndex:		(SInt32)	fieldIndex
error:		(NSError **)	error

Get a field value.

Parameters

recordName	The name of the record.
recordIndex	the index of the record.
fieldName	The name of the field.
fieldIndex	The index of the field.
error	If this method returns nil to indicate that an error occurred then this will be populated with the reason for that failure.

Returns

The field value; or nil if an error occurred, in which case *error will be populated with the failure reason. Reasons for failure include:

• either recordName or fieldName are not defined in the schema.
• either recordIndex or fieldIndex is out of bounds.

Exceptions

NSInvalidArgumentException

If either recordName or fieldName is nil, recordIndex is negative or fieldIndex is negative.

Since

6.0

recordCountWithRecordName:error:

- (nullable NSNumber *) recordCountWithRecordName:		(NSString *)	recordName
error:		(NSError **)	error

Returns the actual number of occurrences of a named record.

If the record is not variable, this is the same as the defined number of occurrences in the schema.

Parameters

recordName	The record name.
error	If this method returns nil to indicate that an error occurred then this will be populated with the reason for that failure.

Returns

The actual number of occurrences of the record as an unsigned integer; or nil if an error occurred, in which case *error will be populated with the failure reason. Reasons for failure include:

• recordName is not defined in the schema.

Exceptions

NSInvalidArgumentException

If recordName is `nil`.

Since

6.0

valueWithError:

- (nullable PTDiffusionRecordV2 *) valueWithError:

(NSError **)

error

Returns an immutable record instance generated from this model; or nil if an error occurred, in which case *error will be populated with the failure reason.

Parameters

error

If this method returns nil to indicate that an error occurred then this will be populated with the reason for that failure.

Returns

Immutable record instance generated from this model.

Since

6.0