com.starbase.util.collections
Class SimpleHashMap

java.lang.Object
  |
  +--com.starbase.util.collections.SimpleHashMap

All Implemented Interfaces:

Map

public class SimpleHashMap

extends java.lang.Object

implements Map

A simple implementation of the Map interface that uses a Hashtable as its underlying implementation. This class does support null values.

Nested Class Summary

Nested classes inherited from class com.starbase.util.collections.Map

Map.Entry

Constructor Summary

SimpleHashMap()
Constructs a new SimpleHashMap.

SimpleHashMap(int initialCapacity)
Constructs a new SimpleHashMap with the specified initial capacity and a load factor of 0.75.

SimpleHashMap(int initialCapacity, float loadFactor)
Constructs a new SimpleHashMap with the specified initial capacity and load factor.

Method Summary

void	clear() Removes all mappings stored in this map (optional operation).
boolean	containsKey(java.lang.Object key) Returns true if the specified key is contained in this map.
boolean	containsValue(java.lang.Object value) Returns true if the specified value is contained in this map.
Set	entrySet() This is currently not implemented.
java.lang.Object	get(java.lang.Object key) Returns the value for the specified key from the map.
boolean	isEmpty() Return true if the map is empty.
Set	keySet() This is currently not implemented.
java.lang.Object	put(java.lang.Object key, java.lang.Object value) Asscociates the specified value with the specified key.
void	putAll(Map map) This operation is unsupported and will throw an exception if called.
java.lang.Object	remove(java.lang.Object key) Removes the key from this map.
int	size() Return the number of entries in this map.
Collection	values() This is currently not implemented.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.starbase.util.collections.Map

equals, hashCode

Constructor Detail

SimpleHashMap

public SimpleHashMap()

Constructs a new SimpleHashMap.

SimpleHashMap

public SimpleHashMap(int initialCapacity)

Constructs a new SimpleHashMap with the specified initial capacity and a load factor of 0.75.

Parameters:

initialCapacity - the initial capacity of this map.

SimpleHashMap

public SimpleHashMap(int initialCapacity,
                     float loadFactor)

Constructs a new SimpleHashMap with the specified initial capacity and load factor. The load factor specifies how full the underlying hash table has to get before its capacity is automatically increased.

Parameters:

initialCapacity - the initial capacity of this map.

loadFactor - the load factor for the underlying hashtable.

Method Detail

size

public int size()

Return the number of entries in this map.

Specified by:

size in interface Map

Returns:

the number of entries in this map.

isEmpty

public boolean isEmpty()

Return true if the map is empty.

Specified by:

isEmpty in interface Map

Returns:

true if the map is empty.

containsKey

public boolean containsKey(java.lang.Object key)

Returns true if the specified key is contained in this map.

Specified by:

containsKey in interface Map

Parameters:

key - the key being checked for in this map.

Returns:

true if the specified key is contained in this map.

containsValue

public boolean containsValue(java.lang.Object value)

Returns true if the specified value is contained in this map. That is ther must be an entry in the map for which a key maps to this value.

Specified by:

containsValue in interface Map

Parameters:

value - the value being checked for in this map

Returns:

true if the specified value is contained in this map.

get

public java.lang.Object get(java.lang.Object key)

Returns the value for the specified key from the map. This may return null.

Specified by:

get in interface Map

Parameters:

key - the key used for lookup in this map.

Returns:

the value for the specified key from the map.

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)

Asscociates the specified value with the specified key. The value is allowed to be null.

Specified by:

put in interface Map

Parameters:

key - the key with which the value is associated

value - the value associated with the key (may be null)

Returns:

the previously associated value with the specified key or null if there was no mapping for the key

remove

public java.lang.Object remove(java.lang.Object key)

Removes the key from this map. May return null.

Specified by:

remove in interface Map

Parameters:

key - the key to be removed

Returns:

the value that was associated with the key (may return null)

putAll

public void putAll(Map map)

This operation is unsupported and will throw an exception if called.

Specified by:

putAll in interface Map

Parameters:

map - the mappings to be stored in this map

clear

public void clear()

Removes all mappings stored in this map (optional operation).

Specified by:

clear in interface Map

keySet

public Set keySet()

This is currently not implemented.

Specified by:

keySet in interface Map

Returns:

nothing, always throws an exception

Throws:

UnsupportedOperationException - always

values

public Collection values()

This is currently not implemented.

Specified by:

values in interface Map

Returns:

nothing, always throws an exception

Throws:

UnsupportedOperationException - always

entrySet

public Set entrySet()

This is currently not implemented.

Specified by:

entrySet in interface Map

Returns:

nothing, always throws an exception

Throws:

UnsupportedOperationException - always