uk.ac.starlink.table
Class UCD

java.lang.Object
  extended byuk.ac.starlink.table.UCD
All Implemented Interfaces:
Comparable

public class UCD
extends Object
implements Comparable

Describes Uniform Column Descriptors. This class knows about all currently defined UCDs, the Unified Column Descriptors defined by the CDS. Each UCD has a unique ID by which it is known, and a description giving a brief explanation of what it means.

UCDs are obtained from the static getUCD(java.lang.String) method; any two UCDs with the same ID are guaranteed to be the same object.

Source of information

The UCD ids and descriptions are read from a list at the resource UCD_DEFINITIONS_LOC. If this resource is unavailable at runtime, a warning will be written to the logging system. The original source of this text file was the CDS List of all UCDs.

See Also:
Unified Content Descriptors

Field Summary
static String UCD_DEFINITIONS_LOC
           
 
Method Summary
 int compareTo(Object other)
          Implements the Comparable interface, comparing alphabetically by ID.
 String getDescription()
          Returns the textual description of the UCD.
 String getID()
          Returns the ID string of this UCD.
static UCD getUCD(String id)
          Returns the UCD object corresponding to a given UCD ID string.
static Iterator getUCDs()
          Returns an iterator over all the known UCDs.
 String toString()
          Returns the UCD id string.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

UCD_DEFINITIONS_LOC

public static final String UCD_DEFINITIONS_LOC
See Also:
Constant Field Values
Method Detail

getID

public String getID()
Returns the ID string of this UCD.

Returns:
the ID string (capitals, underscores and numbers only)

getDescription

public String getDescription()
Returns the textual description of the UCD.

Returns:
a few words describing the meaning of this UCD

compareTo

public int compareTo(Object other)
Implements the Comparable interface, comparing alphabetically by ID.

Specified by:
compareTo in interface Comparable

getUCD

public static UCD getUCD(String id)
Returns the UCD object corresponding to a given UCD ID string. Returns null if no UCD with the given name is known.

Parameters:
id - the string used to identify the UCD (it will have surrounding spaces trimmed)
Returns:
the UCD object corresponding to id, or null if none can be found

getUCDs

public static Iterator getUCDs()
Returns an iterator over all the known UCDs. The iterator returns the UCDs in their natural order (alphabetic by ID).

Returns:
an Iterator which iterates over all the existing UCD objects

toString

public String toString()
Returns the UCD id string.

Returns:
a string representation of this UCD

Copyright © 2004 CLRC: Central Laboratory of the Research Councils. All rights reserved.