Cisco Cisco Prime Optical 10.3 Developer's Guide

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Cisco Prime Optical 10.3 GateWay/CORBA Programmer Reference Guide 
 
 
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Synopsis 
Description 
The how_many parameter determines the maximum number of response entries in the list output 
parameter.  
The iteratorReference parameter provides access to the remaining objects, if any. 
•  If the list contains the complete set of ObjectName objects, then the iteratorReference is a 
reference to a CORBA::Object::_nil object.  
•  If there are more objects, the list output parameter contains the first batch of objects known 
to the EMS and the iteratorReference parameter provides access to the other objects.  
•  If you specify 0 in the how_many parameter, no objects are returned in the list and all objects 
must be retrieved from the iteratorReference parameter. 
The element management layer (EML) can return fewer objects than specified in the how_many 
value under either of the following conditions: 
•  Fewer objects than the number specified in the how_many value actually exist. 
•  The EML determines that the how_many value exceeds the server's stated performance 
restrictions. 
For example, the EML can have 100 objects to return, the network management layer (NML) 
may request 50 through the how_many parameter and the EML may return 20 along with an 
iteratorReference. 
The NMS uses the iteratorReference parameter to request further batches. This reference can be 
used to query how many objects can be returned by the getLength method. The NMS can 
subsequently start retrieving or removing the iterator. If all objects are specified in the list, it is a 
reference to a CORBA::Object::_nil object.  
Each entry is returned only once, so you must use the next_n method to retrieve the additional 
entries in the selected set.  
The EML may not get the total number of elements returned by the iterator in the following 
instances: 
•  The EML has to fetch all of the data that has been requested and then count the number of 
elements. This may not produce the desired results.  
•  The EML may be able to get a count of the number of elements, but due to concurrent 
modifications, the actual number may vary over the time of the iteration. 
The interface client can determine when all data has been collected by repeatedly fetching 
chunks of data until the iterator indicates that no further data remains. If the EMS is unable to 
determine the length, the getLength method returns the EXCPT_CAPACITY_EXCEEDED 
exception. 
The EXCPT_TOO_MANY_OPEN_ITERATORS exception is returned if the EMS has reached 
an implementation limitation. An EMS supports a minimum of 10 iterators. 
In this interface, the iterators have the following operations: 
•  getLength—Returns the total number of elements in the iterator. For example, if the EML 
has 100 objects and 10 are returned in the initial list, the getLength method should return 90,