PCJ API
Version 1.2

bak.pcj.adapter
Class MapToObjectKeyLongMapAdapter

java.lang.Object
  extended bybak.pcj.map.AbstractObjectKeyLongMap
      extended bybak.pcj.adapter.MapToObjectKeyLongMapAdapter
All Implemented Interfaces:
ObjectKeyLongMap

public class MapToObjectKeyLongMapAdapter
extends AbstractObjectKeyLongMap
implements ObjectKeyLongMap

This class represents adaptions of Java Collections Framework maps to primitive maps from object values to long values. The adapter is implemented as a wrapper around the map. Thus, changes to the underlying map are reflected by this map and vice versa.

Adapters from JCF maps to primitive map will fail if the JCF collection contains null values or values of the wrong class. However, adapters are not fast failing in the case that the underlying map should contain illegal keys or values. To implement fast failure would require every operation to check every key and value of the underlying map before doing anything. Instead validation methods are provided. They can be called using the assertion facility in the client code:

      MapToObjectKeyLongMapAdapter s;
      ...
      assert s.validate();
  
or by letting the adapter throw an exception on illegal values:
      MapToObjectKeyLongMapAdapter s;
      ...
      s.evalidate();  // Throws an exception on illegal values
  
Either way, validation must be invoked directly by the client code.

Since:
1.1

Field Summary
protected  Long lastValue
          The value corresponding to the last key found by containsKey().
protected  Map map
          The underlying map.
 
Constructor Summary
MapToObjectKeyLongMapAdapter(Map map)
          Creates a new adaption to a map from object values to long values.
MapToObjectKeyLongMapAdapter(Map map, boolean validate)
          Creates a new adaption to a map from object values to long values.
 
Method Summary
 void clear()
          Clears this map.
 boolean containsKey(Object key)
          Indicates whether this map contains a mapping from a specified key.
 boolean containsValue(long value)
          Indicates whether this map contains a mapping to a specified value.
 ObjectKeyLongMapIterator entries()
          Returns an iterator over the entries of this map.
 void evalidate()
          Validates the map underlying this adapter and throws an exception if it is invalid.
 long get(Object key)
          Maps a specified key to a value.
 Set keySet()
          Returns a set view of the keys of this map.
 long lget()
          Returns the last value corresponding to a positive result from containsKey(Object).
 long put(Object key, long value)
          Adds a mapping from a specified key to a specified value to this map.
 long remove(Object key)
          Removes the mapping from a specified key from this map.
 int size()
          Returns the size of this map.
 long tget(Object key)
          Maps a specified key to a value.
 boolean validate()
          Indicates whether the underlying map is valid for this adapter.
 LongCollection values()
          Returns a collection view of the values in this map.
 
Methods inherited from class bak.pcj.map.AbstractObjectKeyLongMap
equals, hashCode, isEmpty, putAll, toString, trimToSize
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface bak.pcj.map.ObjectKeyLongMap
equals, hashCode, isEmpty, putAll, trimToSize
 

Field Detail

map

protected Map map
The underlying map.


lastValue

protected Long lastValue
The value corresponding to the last key found by containsKey().

Constructor Detail

MapToObjectKeyLongMapAdapter

public MapToObjectKeyLongMapAdapter(Map map)
Creates a new adaption to a map from object values to long values.

Parameters:
map - the underlying map. This map must consist of values of class Long. Otherwise a ClassCastException will be thrown by some methods.
Throws:
NullPointerException - if map is null.

MapToObjectKeyLongMapAdapter

public MapToObjectKeyLongMapAdapter(Map map,
                                    boolean validate)
Creates a new adaption to a map from object values to long values. The map to adapt is optionally validated.

Parameters:
map - the underlying map. This map must consist of values of class Long. Otherwise a ClassCastException will be thrown by some methods.
validate - indicates whether map should be checked for illegal values.
Throws:
NullPointerException - if map is null.
IllegalStateException - if validate is true and map contains a null value, or a value that is not of class Long.
Method Detail

clear

public void clear()
Description copied from interface: ObjectKeyLongMap
Clears this map.

Specified by:
clear in interface ObjectKeyLongMap
Overrides:
clear in class AbstractObjectKeyLongMap

containsKey

public boolean containsKey(Object key)
Description copied from interface: ObjectKeyLongMap
Indicates whether this map contains a mapping from a specified key. If the key is contained in this map, a succeeding call to lget() will return the corresponding value.

Specified by:
containsKey in interface ObjectKeyLongMap
Overrides:
containsKey in class AbstractObjectKeyLongMap

containsValue

public boolean containsValue(long value)
Description copied from interface: ObjectKeyLongMap
Indicates whether this map contains a mapping to a specified value.

Specified by:
containsValue in interface ObjectKeyLongMap
Overrides:
containsValue in class AbstractObjectKeyLongMap

entries

public ObjectKeyLongMapIterator entries()
Description copied from interface: ObjectKeyLongMap
Returns an iterator over the entries of this map. It is possible to remove entries from this map using the iterator provided that the concrete map supports removal of entries.

Specified by:
entries in interface ObjectKeyLongMap
Returns:
an iterator over the entries of this map.

get

public long get(Object key)
Description copied from interface: ObjectKeyLongMap
Maps a specified key to a value. Returns a default value as specified by the MapDefaults class if no mapping exists for the specified key.

Specified by:
get in interface ObjectKeyLongMap
Overrides:
get in class AbstractObjectKeyLongMap

keySet

public Set keySet()
Description copied from interface: ObjectKeyLongMap
Returns a set view of the keys of this map. Removals from the returned set removes the corresponding entries in this map. Changes to the map are reflected in the set.

Specified by:
keySet in interface ObjectKeyLongMap
Returns:
a set view of the keys of this map.

lget

public long lget()
Description copied from interface: ObjectKeyLongMap
Returns the last value corresponding to a positive result from containsKey(Object). This is useful for checking checking the existence of a mapping while avoiding two lookups on the same key.

Specified by:
lget in interface ObjectKeyLongMap
Returns:
the value corresponding to the key from the last invokation of containsKey(Object).
See Also:
ObjectKeyLongMap.get(Object), ObjectKeyLongMap.tget(Object), ObjectKeyLongMap.containsKey(Object)

put

public long put(Object key,
                long value)
Description copied from interface: ObjectKeyLongMap
Adds a mapping from a specified key to a specified value to this map. If a mapping already exists for the specified key it is overwritten by the new mapping.

Specified by:
put in interface ObjectKeyLongMap
Parameters:
key - the key of the mapping to add to this map.
value - the value of the mapping to add to this map.
Returns:
the old value if a mapping from the specified key already existed in this map; otherwise returns a default value as specified by the MapDefaults class.
See Also:
MapDefaults

remove

public long remove(Object key)
Description copied from interface: ObjectKeyLongMap
Removes the mapping from a specified key from this map.

Specified by:
remove in interface ObjectKeyLongMap
Overrides:
remove in class AbstractObjectKeyLongMap

size

public int size()
Description copied from interface: ObjectKeyLongMap
Returns the size of this map. The size is defined as the number of mappings from keys to values.

Specified by:
size in interface ObjectKeyLongMap
Overrides:
size in class AbstractObjectKeyLongMap

values

public LongCollection values()
Description copied from interface: ObjectKeyLongMap
Returns a collection view of the values in this map. The collection is not modifiable, but changes to the map are reflected in the collection.

Specified by:
values in interface ObjectKeyLongMap
Returns:
a collection view of the values in this map.

tget

public long tget(Object key)
Description copied from interface: ObjectKeyLongMap
Maps a specified key to a value. This method should be used when the key is known to be in the map.

Specified by:
tget in interface ObjectKeyLongMap
Overrides:
tget in class AbstractObjectKeyLongMap

validate

public boolean validate()
Indicates whether the underlying map is valid for this adapter. For the underlying map to be valid it can contain no null values and only Long values.

Returns:
true if the underlying map is valid; returns false otherwise.

evalidate

public void evalidate()
Validates the map underlying this adapter and throws an exception if it is invalid. For the underlying map to be valid it can contain no null values and only Long values.

Throws:
IllegalStateException - if the underlying map is invalid.

PCJ API
Version 1.2

Report a bug or request a feature.
Further information on the development and latest release of PCJ can be found at the project homepage.

Primitive Collections for Java is released under the GNU Lesser General Public License.
Copyright © 2002, 2003 Søren Bak. All Rights Reserved.

Hosted by SourceForge.net
SourceForge.net Logo