Package org.astrogrid.samp

Class SampMap

java.lang.Object
java.util.AbstractMap
org.astrogrid.samp.SampMap
All Implemented Interfaces:
Map
Direct Known Subclasses:
ErrInfo, LockInfo, Message, Metadata, RegInfo, Response, Subscriptions
public abstract class SampMap extends AbstractMap
Abstract superclass for objects represented within the SAMP package as key-value maps. There are several of these, represented by subclasses of SampMap, for instance Message, Metadata etc. A SampMap is-a Map, but has some additional useful features:
  • its entries are ordered in a convenient fashion
  • it contains some general-purpose utility methods appropriate to SAMP maps
  • particular subclasses contain specific constants and utility methods, e.g. well-known keys and accessor methods for them
  • concrete subclasses provide a static asClass method to convert from a normal Map to the class in question

In general any time a map-encoded object is required by a method in the toolkit, any Map can be used. When the toolkit provides a map-encoded object however (as return value or callback method parameter), an object of the more specific SampMap type is used. This allows maximum convenience for the application programmer, but means that you don't have to use these additional features if you don't want to, you can treat everything as a plain old Map.

Since:
14 Jul 2008
Author:
Mark Taylor

  • Field Details

    • EMPTY

      public static final Map EMPTY

  • Constructor Details

    • SampMap

      protected SampMap(String[] knownKeys)
      Constructor. The given array of well-known keys will appear first in the list of entries when this map is iterated over. Other entries will appear in alphabetical order.
      Parameters:
      knownKeys - array of well-known keys for this class

  • Method Details

    • put

      public Object put(Object key, Object value)
      Specified by:
      put in interface Map
      Overrides:
      put in class AbstractMap

    • entrySet

      public Set entrySet()
      Specified by:
      entrySet in interface Map
      Specified by:
      entrySet in class AbstractMap

    • check

      public void check()
      Checks that this object is ready for use with the SAMP toolkit. As well as calling SampUtils.checkMap(java.util.Map) (ensuring that all keys are Strings, and all values Strings, Lists or Maps), subclass-specific invariants may be checked. In the case that there's something wrong, an informative DataException will be thrown.
      Throws:
      DataException - if this object's current state is not suitable for SAMP use

    • checkHasKeys

      public void checkHasKeys(String[] keys)
      Checks that this map contains at least the given set of keys. If any is absent, an informative DataException will be thrown. Normally called by check().
      Parameters:
      keys - array of required keys for this map
      Throws:
      DataException - if this object does not contain entries for all elements of the array keys

    • getString

      public String getString(String key)
      Returns the value for a given key in this map, cast to String.
      Returns:
      string value for key

    • getMap

      public Map getMap(String key)
      returns the value for a given key in this map, cast to Map.
      Returns:
      map value for key

    • getList

      public List getList(String key)
      Returns the value for a given key in this map, cast to List.
      Returns:
      list value for key

    • getUrl

      public URL getUrl(String key)
      Returns the value for a given key in this map as a URL.
      Returns:
      URL value for key