PIP.Collections.Persistent
Class SHashMap<K,V>

java.lang.Object
  PIP.Collections.Persistent.AbstractMap<K,V>
      PIP.Collections.Persistent.SHashMap<K,V>

All Implemented Interfaces:

java.io.Serializable, java.util.Map<K,V>

public class SHashMap<K,V>
extends AbstractMap<K,V>
implements java.io.Serializable

JDO requires classes to be enhanced in order to serialise those objects. However, JDO explicitly recognises the collection classes so that they can be used as member variables without being enhanced and also so that they map cleanly to referential structures. However, this mechanism does not allow collections to be persisted in other circumstances such when they are used as values in a map or collections of collections. In order to persist use collections a first class persistence capable object I have created a new set of classes prefixed by S that mirror those contained with the Java.utils package. This has pattern has also been provided directly in other JDO implementations. Therefore, this class if an exact replication of the standard Java jdk HashMap class

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

java.util.Map.Entry<K,V>

Constructor Summary

SHashMap()

Method Summary

java.util.Set<java.util.Map.Entry<K,V>>	entrySet() Returns a set view of the mappings contained in this map.
V	put(K key, V value) Associates the specified value with the specified key in this map (optional operation).

Methods inherited from class PIP.Collections.Persistent.AbstractMap

clear, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, putAll, remove, size, toString, values

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SHashMap

public SHashMap()

Method Detail

entrySet

public java.util.Set<java.util.Map.Entry<K,V>> entrySet()

Description copied from class: AbstractMap

Returns a set view of the mappings contained in this map. Each element in this set is a Map.Entry. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. (If the map is modified while an iteration over the set is in progress, the results of the iteration are undefined.) The set supports element removal, which removes the corresponding entry from the map, via the Iterator.remove, Set.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Specified by:

entrySet in interface java.util.Map<K,V>

Specified by:

entrySet in class AbstractMap<K,V>

Returns:

a set view of the mappings contained in this map.

put

public V put(K key,
             V value)

Description copied from class: AbstractMap

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for this key, the old value is replaced.

This implementation always throws an UnsupportedOperationException.

Specified by:

put in interface java.util.Map<K,V>

Overrides:

put in class AbstractMap<K,V>

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

previous value associated with specified key, or null if there was no mapping for key. (A null return can also indicate that the map previously associated null with the specified key, if the implementation supports null values.)