org.datanucleus.store.types.sco.backed
Class Hashtable

java.lang.Object
  extended by java.util.Dictionary<K,V>
      extended by java.util.Hashtable
          extended by org.datanucleus.store.types.sco.simple.Hashtable
              extended by org.datanucleus.store.types.sco.backed.Hashtable
All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, java.util.Map, SCO, SCOContainer, SCOMap

public class Hashtable
extends Hashtable

A mutable second-class Hashtable object. Backed by a MapStore object.

See Also:
Serialized Form

Field Summary
protected  boolean allowNulls
           
protected  MapStore backingStore
           
protected  boolean isCacheLoaded
           
protected  OperationQueue<MapStore> operationQueue
           
protected  boolean queued
           
protected  boolean useCache
           
 
Fields inherited from class org.datanucleus.store.types.sco.simple.Hashtable
delegate, fieldName, fieldNumber, LOCALISER, owner, ownerSM
 
Constructor Summary
Hashtable(ObjectProvider ownerSM, java.lang.String fieldName)
          Constructor
 
Method Summary
protected  void addQueuedOperation(QueuedOperation<? super MapStore> op)
          Convenience method to add a queued operation to the operations we perform at commit.
 void clear()
          Method to clear the Hashtable
 java.lang.Object clone()
          Creates and returns a copy of this object.
 boolean containsKey(java.lang.Object key)
          Method to return if the map contains this key
 boolean containsValue(java.lang.Object value)
          Method to return if the map contains this value.
 java.util.Set entrySet()
          Accessor for the set of entries in the Map.
 boolean equals(java.lang.Object o)
          Method to check the equality of this map, and another.
 void flush()
          Method to flush the changes to the datastore when operating in queued mode.
 java.lang.Object get(java.lang.Object key)
          Accessor for the value stored against a key.
 java.lang.Object getValue()
          Accessor for the unwrapped value that we are wrapping.
 int hashCode()
          Method to generate a hashcode for this Map.
 void initialise()
          Method to initialise the SCO for use.
 void initialise(java.lang.Object o, boolean forInsert, boolean forUpdate)
          Method to initialise the SCO from an existing value.
 boolean isEmpty()
          Method to return if the Map is empty.
 boolean isLoaded()
          Method to return if the SCO has its contents loaded.
 java.util.Set keySet()
          Accessor for the set of keys in the Map.
 void load()
          Method to effect the load of the data in the SCO.
protected  void loadFromStore()
          Method to load all elements from the "backing store" where appropriate.
 java.lang.Object put(java.lang.Object key, java.lang.Object value)
          Method to add a value against a key to the Hashtable
 void putAll(java.util.Map m)
          Method to add the specified Map's values under their keys here.
 java.lang.Object remove(java.lang.Object key)
          Method to remove the value for a key from the Hashtable
 int size()
          Method to return the size of the Map.
 void unsetOwner()
          Method to unset the owner and field details.
 void updateEmbeddedKey(java.lang.Object key, int fieldNumber, java.lang.Object newValue)
          Method to update an embedded key in this map.
 void updateEmbeddedValue(java.lang.Object value, int fieldNumber, java.lang.Object newValue)
          Method to update an embedded value in this map.
 java.util.Collection values()
          Accessor for the set of values in the Map.
protected  java.lang.Object writeReplace()
          The writeReplace method is called when ObjectOutputStream is preparing to write the object to the stream.
 
Methods inherited from class org.datanucleus.store.types.sco.simple.Hashtable
attachCopy, detachCopy, getFieldName, getOwner, makeDirty
 
Methods inherited from class java.util.Hashtable
contains, elements, keys, rehash, toString
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

backingStore

protected transient MapStore backingStore

allowNulls

protected transient boolean allowNulls

useCache

protected transient boolean useCache

isCacheLoaded

protected transient boolean isCacheLoaded

queued

protected transient boolean queued

operationQueue

protected transient OperationQueue<MapStore> operationQueue
Constructor Detail

Hashtable

public Hashtable(ObjectProvider ownerSM,
                 java.lang.String fieldName)
Constructor

Parameters:
ownerSM - the owner of this Map
fieldName - the declared field name
Method Detail

initialise

public void initialise(java.lang.Object o,
                       boolean forInsert,
                       boolean forUpdate)
Method to initialise the SCO from an existing value.

Specified by:
initialise in interface SCO
Overrides:
initialise in class Hashtable
Parameters:
o - Object to set value using.
forInsert - Whether the object needs inserting in the datastore with this value
forUpdate - Whether to update the datastore with this value

initialise

public void initialise()
Method to initialise the SCO for use.

Specified by:
initialise in interface SCO
Overrides:
initialise in class Hashtable

getValue

public java.lang.Object getValue()
Accessor for the unwrapped value that we are wrapping.

Specified by:
getValue in interface SCO
Overrides:
getValue in class Hashtable
Returns:
The unwrapped value

load

public void load()
Method to effect the load of the data in the SCO. Used when the SCO supports lazy-loading to tell it to load all now.

Specified by:
load in interface SCOContainer
Overrides:
load in class Hashtable

isLoaded

public boolean isLoaded()
Method to return if the SCO has its contents loaded. If the SCO doesn't support lazy loading will just return true.

Specified by:
isLoaded in interface SCOContainer
Overrides:
isLoaded in class Hashtable
Returns:
Whether it is loaded

loadFromStore

protected void loadFromStore()
Method to load all elements from the "backing store" where appropriate.


flush

public void flush()
Method to flush the changes to the datastore when operating in queued mode. Does nothing in "direct" mode.

Specified by:
flush in interface SCOContainer
Overrides:
flush in class Hashtable

addQueuedOperation

protected void addQueuedOperation(QueuedOperation<? super MapStore> op)
Convenience method to add a queued operation to the operations we perform at commit.

Parameters:
op - The operation

updateEmbeddedKey

public void updateEmbeddedKey(java.lang.Object key,
                              int fieldNumber,
                              java.lang.Object newValue)
Method to update an embedded key in this map.

Specified by:
updateEmbeddedKey in interface SCOMap
Overrides:
updateEmbeddedKey in class Hashtable
Parameters:
key - The key
fieldNumber - Number of field in the key
newValue - New value for this field

updateEmbeddedValue

public void updateEmbeddedValue(java.lang.Object value,
                                int fieldNumber,
                                java.lang.Object newValue)
Method to update an embedded value in this map.

Specified by:
updateEmbeddedValue in interface SCOMap
Overrides:
updateEmbeddedValue in class Hashtable
Parameters:
value - The value
fieldNumber - Number of field in the value
newValue - New value for this field

unsetOwner

public void unsetOwner()
Method to unset the owner and field details.

Specified by:
unsetOwner in interface SCO
Overrides:
unsetOwner in class Hashtable

clone

public java.lang.Object clone()
Creates and returns a copy of this object.

Mutable second-class Objects are required to provide a public clone method in order to allow for copying PersistenceCapable objects. In contrast to Object.clone(), this method must not throw a CloneNotSupportedException.

Specified by:
clone in interface SCO
Overrides:
clone in class Hashtable
Returns:
The cloned object

containsKey

public boolean containsKey(java.lang.Object key)
Method to return if the map contains this key

Specified by:
containsKey in interface java.util.Map
Overrides:
containsKey in class Hashtable
Parameters:
key - The key
Returns:
Whether it is contained

containsValue

public boolean containsValue(java.lang.Object value)
Method to return if the map contains this value.

Specified by:
containsValue in interface java.util.Map
Overrides:
containsValue in class Hashtable
Parameters:
value - The value
Returns:
Whether it is contained

entrySet

public java.util.Set entrySet()
Accessor for the set of entries in the Map.

Specified by:
entrySet in interface java.util.Map
Overrides:
entrySet in class Hashtable
Returns:
Set of entries

equals

public boolean equals(java.lang.Object o)
Method to check the equality of this map, and another.

Specified by:
equals in interface java.util.Map
Overrides:
equals in class Hashtable
Parameters:
o - The map to compare against.
Returns:
Whether they are equal.

get

public java.lang.Object get(java.lang.Object key)
Accessor for the value stored against a key.

Specified by:
get in interface java.util.Map
Overrides:
get in class Hashtable
Parameters:
key - The key
Returns:
The value.

hashCode

public int hashCode()
Method to generate a hashcode for this Map.

Specified by:
hashCode in interface java.util.Map
Overrides:
hashCode in class Hashtable
Returns:
The hashcode.

isEmpty

public boolean isEmpty()
Method to return if the Map is empty.

Specified by:
isEmpty in interface java.util.Map
Overrides:
isEmpty in class Hashtable
Returns:
Whether it is empty.

keySet

public java.util.Set keySet()
Accessor for the set of keys in the Map.

Specified by:
keySet in interface java.util.Map
Overrides:
keySet in class Hashtable
Returns:
Set of keys.

size

public int size()
Method to return the size of the Map.

Specified by:
size in interface java.util.Map
Overrides:
size in class Hashtable
Returns:
The size

values

public java.util.Collection values()
Accessor for the set of values in the Map.

Specified by:
values in interface java.util.Map
Overrides:
values in class Hashtable
Returns:
Set of values.

clear

public void clear()
Method to clear the Hashtable

Specified by:
clear in interface java.util.Map
Overrides:
clear in class Hashtable

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)
Method to add a value against a key to the Hashtable

Specified by:
put in interface java.util.Map
Overrides:
put in class Hashtable
Parameters:
key - The key
value - The value
Returns:
The previous value for the specified key.

putAll

public void putAll(java.util.Map m)
Method to add the specified Map's values under their keys here.

Specified by:
putAll in interface java.util.Map
Overrides:
putAll in class Hashtable
Parameters:
m - The map

remove

public java.lang.Object remove(java.lang.Object key)
Method to remove the value for a key from the Hashtable

Specified by:
remove in interface java.util.Map
Overrides:
remove in class Hashtable
Parameters:
key - The key to remove
Returns:
The value that was removed from this key.

writeReplace

protected java.lang.Object writeReplace()
                                 throws java.io.ObjectStreamException
The writeReplace method is called when ObjectOutputStream is preparing to write the object to the stream. The ObjectOutputStream checks whether the class defines the writeReplace method. If the method is defined, the writeReplace method is called to allow the object to designate its replacement in the stream. The object returned should be either of the same type as the object passed in or an object that when read and resolved will result in an object of a type that is compatible with all references to the object.

Overrides:
writeReplace in class Hashtable
Returns:
the replaced object
Throws:
java.io.ObjectStreamException


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