gate.util
Class SimpleMapImpl

java.lang.Object
  gate.util.SimpleMapImpl

All Implemented Interfaces:

Serializable, Cloneable, Map<Object,Object>

Direct Known Subclasses:

SimpleFeatureMapImpl

 class SimpleMapImpl
extends Object
implements Map<Object,Object>, Cloneable, Serializable

Implements Map interface in using less memory. Very simple but usefull for small number of items on it.

Nested Class Summary

private static class	SimpleMapImpl.Entry Auxiliary classes needed for the support of entrySet() method
private static class	SimpleMapImpl.NullKey Special marker class used to represent null in the keys array.

Field Summary

(package private) int	capacity The capacity of the map
(package private) int	count The current number of elements of the map
(package private) static Object	nullKey the Object instance that will represent the NULL keys in the map
(package private) static long	serialVersionUID Freeze the serialization UID.
(package private) Object[]	theKeys Array keeping the keys of the entries in the map.
static ConcurrentHashMap	theKeysHere the static 'all keys' collection
(package private) Object[]	theValues Array keeping the values of the entries in the map.

Constructor Summary

SimpleMapImpl()
Constructor

Method Summary

void	clear() clear the map
Object	clone() Create a copy of the map including the data.
boolean	containsKey(Object key) return true if the key is in the map
boolean	containsValue(Object value) return true if the map contains that value
Set	entrySet()
boolean	equals(Object o)
Object	get(Object key) return the value associated with the key.
private int	getPostionByKey(Object key) return positive value as index of the key in the map.
private int	getPostionByValue(Object value) return positive value as index of the value in the map.
protected int	getSubsumeKey(Object key) return the index of the key in the map comparing them by reference only.
int	hashCode() return the hashCode for the map
private void	increaseCapacity()
boolean	isEmpty() return true if there are no elements in the map
Set	keySet() return the set of the keys in the map.
Object	put(Object key, Object value) put a value in the map using the given key.
void	putAll(Map t) put all the elements from a map
private void	readObject(ObjectInputStream s) readObject - calls the default readObject() and then initialises the transient data
Object	remove(Object key) remove value from the map using it's key.
int	size() return the number of elements in the map
String	toString()
Collection	values() Not supported.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

capacity

int capacity

The capacity of the map

count

int count

The current number of elements of the map

theKeys

Object[] theKeys

Array keeping the keys of the entries in the map. It is "synchrnized" with the values array - the Nth position in both arrays correspond to one and the same entry

theValues

Object[] theValues

Array keeping the values of the entries in the map. It is "synchrnized" with the keys array - the Nth position in both arrays correspond to one and the same entry

serialVersionUID

static final long serialVersionUID

Freeze the serialization UID.

See Also:

Constant Field Values

nullKey

static transient Object nullKey

the Object instance that will represent the NULL keys in the map

theKeysHere

public static transient ConcurrentHashMap theKeysHere

the static 'all keys' collection

Constructor Detail

SimpleMapImpl

public SimpleMapImpl()

Constructor

Method Detail

size

public int size()

return the number of elements in the map

Specified by:

size in interface Map<Object,Object>

isEmpty

public boolean isEmpty()

return true if there are no elements in the map

Specified by:

isEmpty in interface Map<Object,Object>

values

public Collection values()

Not supported. This method is here only to conform the Map interface

Specified by:

values in interface Map<Object,Object>

keySet

public Set keySet()

return the set of the keys in the map. The changes in the set DO NOT affect the map.

Specified by:

keySet in interface Map<Object,Object>

clear

public void clear()

clear the map

Specified by:

clear in interface Map<Object,Object>

containsKey

public boolean containsKey(Object key)

return true if the key is in the map

Specified by:

containsKey in interface Map<Object,Object>

containsValue

public boolean containsValue(Object value)

return true if the map contains that value

Specified by:

containsValue in interface Map<Object,Object>

get

public Object get(Object key)

return the value associated with the key. If the key is not in the map returns null.

Specified by:

get in interface Map<Object,Object>

put

public Object put(Object key,
                  Object value)

put a value in the map using the given key. If the key exist in the map the value is replaced and the old one is returned.

Specified by:

put in interface Map<Object,Object>

remove

public Object remove(Object key)

remove value from the map using it's key.

Specified by:

remove in interface Map<Object,Object>

putAll

public void putAll(Map t)

put all the elements from a map

Specified by:

putAll in interface Map<Object,Object>

getPostionByKey

private int getPostionByKey(Object key)

return positive value as index of the key in the map. Negative value means that the key is not present in the map

getSubsumeKey

protected int getSubsumeKey(Object key)

return the index of the key in the map comparing them by reference only. This method is used in subsume check to speed it up.

getPostionByValue

private int getPostionByValue(Object value)

return positive value as index of the value in the map.

increaseCapacity

private void increaseCapacity()

entrySet

public Set entrySet()

Specified by:

entrySet in interface Map<Object,Object>

equals

public boolean equals(Object o)

Specified by:

equals in interface Map<Object,Object>

Overrides:

equals in class Object

hashCode

public int hashCode()

return the hashCode for the map

Specified by:

hashCode in interface Map<Object,Object>

Overrides:

hashCode in class Object

clone

public Object clone()

Create a copy of the map including the data.

Overrides:

clone in class Object

toString

public String toString()

Overrides:

toString in class Object

readObject

private void readObject(ObjectInputStream s)
                 throws IOException,
                        ClassNotFoundException

readObject - calls the default readObject() and then initialises the transient data

Throws:

IOException

ClassNotFoundException