function __construct($type_uri, $count, $required, $alias)
{
/**
* required: Whether the attribute will be marked as required
* when presented to the subject of the attribute exchange
* request.
*/
$this->required = $required;
/**
* count: How many values of this type to request from the
* subject. Defaults to one.
*/
$this->count = $count;
/**
* type_uri: The identifier that determines what the attribute
* represents and how it is serialized. For example, one type
* URI representing dates could represent a Unix timestamp in
* base 10 and another could represent a human-readable
* string.
*/
$this->type_uri = $type_uri;
/**
* alias: The name that should be given to this attribute in
* the request. If it is not supplied, a generic name will be
* assigned. For example, if you want to call a Unix timestamp
* value 'tstamp', set its alias to that value. If two
* attributes in the same message request to use the same
* alias, the request will fail to be generated.
*/
$this->alias = $alias;
}