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Class com.las.ogdi.OGDICoverage 

java.lang.Object
   |
   +----com.las.ogdi.OGDICoverage
public class OGDICoverage
extends Object
The Coverage class defines a request and family for accessing a given coverage. Coverage defines the layer upon which subsequent calls to coverage-oriented commands act. The coverage syntax will change according to the driver (data format) used. In its simplest way a coverage will be defined as follows: 
   OGDIcoverage(OGDIFamily.FAMILY,"coveragename");
A more general way of describing the coverage will be: 
   OGDIcoverage(OGDIFamily.FAMILY,"tablename@coveragename(qualifier)");
where 
  - tablename is used to describe a mapset or group containing several 
 coverages (map layers);
  - @ is used to separate tablename and coveragename;
  - coveragename is the name of the coverage being accessed;
  - (qualifier) is used to select a group of objects from the coverage 
 that responds to a specific characteristic or spatial query;
Here is an example with the VRF driver: 
  OGDIUrl("gltp:/vrf/c:/forthood/VMAPLV2/TEXASH");
  OGDICoverage(OGDIFamily.Line, "contourl@elev(*)");
The (*) means that all the objects of the coverage will be selected. The following example shows that a spatial query can be made to select objects that respond to the query. 
  OGDIUrl("gltp:/VRF/d:/west_lv1/bc");
  OGDICoverage(OGDIFamily.Line, "depthl@elev(acc=2)");
where 
  acc is the "Accuracy Category"
     1 = Accurate
     2 = Approximate
Here is the list of valid operators for building a query: AND, OR, =, !=, <, >, <= and >= . 

 Even though most geospatial data formats will fall within this description, 
 there are some exceptions. The User's Manual better describes how to access 
 a coverage for each data format, with examples for each drivers.




  
 Version:
  
 1.0
  
 Author:
  
 Las Inc.







  Constructor Index




  
  o 
	OGDICoverage(OGDIFamily, String)
  
  Creates a Coverage.




  Method Index




  
  o 
	getFamily()
  
  Gets the family.
  
  o 
	getRequest()
  
  Gets the request for a coverage.
  
  o 
	toString()
  
  Gets the complete coverage.





  Constructors



 o 
OGDICoverage

 public OGDICoverage(OGDIFamily family,
                     String request)




  
 Creates a Coverage.
 Note: the request can be passed directly without validation but it is better
 to validate it through a call to the Dictionary's syntaxModel with getRequest.


  

    
 Parameters:
    
 family - a family type
    
 request - a request.
    
 Returns:
    
 nothing
    
 Throws: IllegalArgumentException
    
 if family or request is null
  






  Methods


 o 
getFamily

 public OGDIFamily getFamily()




  
 Gets the family.


  

    
 Parameters:
    
 no - parameter
    
 Returns:
    
 the family
    
 Throws: no
    
 exception
  



 o 
getRequest

 public String getRequest()




  
 Gets the request for a coverage.


  

    
 Parameters:
    
 no - parameter
    
 Returns:
    
 the request
    
 Throws: no
    
 exception
  



 o 
toString

 public String toString()




  
 Gets the complete coverage.


  

    
 Parameters:
    
 no - parameter
    
 Returns:
    
 the coverage family and request as a string
    
 Throws: no
    
 exception
    
 Overrides:
    
 toString in class Object
  






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