org.conqat.lib.commons.collections

Class TwoDimHashMap<K1,K2,V>

java.lang.Object

org.conqat.lib.commons.collections.TwoDimHashMap<K1,K2,V>

public class TwoDimHashMap<K1,K2,V>
extends java.lang.Object

A 2-dimensional hash map. Allows storage of items identified by two different keys. This can be used to store the following data structure:

• Project A
  • Dan — Testing
  • Flo — Documentation
• Project B
  • Flo — Design
  • Dan — QA
  • Markus — CM
  • Jorge — Testing

Constructor Summary

Constructors

Constructor and Description
TwoDimHashMap() Create a new doubly hashed map.
TwoDimHashMap(java.util.Map<K1,java.util.Map<K2,V>> map) Create a new two dimensional map using the data in the given map.

Method Summary

Modifier and Type	Method and Description
void	clear() Clear the whole map.
boolean	containsKey(K1 firstKey, K2 secondKey) Returns whether the given key combination is available in the map.
java.util.Set<K1>	getFirstKeys() Get all first level keys.
java.util.Set<K2>	getSecondKeys(K1 firstKey) Get all the second level keys stored under the given first level key.
UnmodifiableMap<K2,V>	getSecondMap(K1 key) Returns the data stored under the given first-level key as an unmodifiable map or null if nothing is stored under that key.
int	getSecondSize(K1 key1) Get the size of the (second) map stored for a first key.
int	getSize() Get size of the map.
V	getValue(K1 firstKey, K2 secondKey) Get a value by specifying first and second level key.
java.util.List<V>	getValues() Get all values stored in the map.
java.util.Collection<V>	getValuesByFirstKey(K1 firstKey) Get all values referenced by a first level key.
java.util.List<V>	getValuesBySecondKey(K2 secondKey) Get all values referenced by a second level key.
boolean	isEmpty() Check if the map is empty, i.e.
void	putAll(TwoDimHashMap<K1,K2,V> otherMap) Put all values of another TwoDimHashMap into this map.
void	putValue(K1 key1, K2 key2, V value) Puts the given value into this map under the given keys.
boolean	remove(K1 key) Remove all values stored under the given first level key.
V	remove(K1 key1, K2 key2) Removes the value associated with the given key combination.

Methods inherited from class java.lang.Object

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

Constructor Detail

TwoDimHashMap

public TwoDimHashMap()

Create a new doubly hashed map.

TwoDimHashMap

public TwoDimHashMap(java.util.Map<K1,java.util.Map<K2,V>> map)

Create a new two dimensional map using the data in the given map.

Method Detail

putAll

public void putAll(TwoDimHashMap<K1,K2,V> otherMap)

Put all values of another TwoDimHashMap into this map.

putValue

public void putValue(K1 key1,
                     K2 key2,
                     V value)

Puts the given value into this map under the given keys. Any potentially existing value will be overwritten.

Parameters:

key1 - first level key

key2 - second level key

value - the value

getValue

public V getValue(K1 firstKey,
                  K2 secondKey)

Get a value by specifying first and second level key.

Parameters:

firstKey - first level key

secondKey - second level key

Returns:

the value. Is null if first or second level key does not exist or if null was explicitly stored.

containsKey

public boolean containsKey(K1 firstKey,
                           K2 secondKey)

Returns whether the given key combination is available in the map.

Parameters:

firstKey - first level key

secondKey - second level key

getValuesByFirstKey

public java.util.Collection<V> getValuesByFirstKey(K1 firstKey)

Get all values referenced by a first level key.

Parameters:

firstKey - the first level key

Returns:

a list of values referenced by the specified first level key

getFirstKeys

public java.util.Set<K1> getFirstKeys()

Get all first level keys.

getSecondKeys

public java.util.Set<K2> getSecondKeys(K1 firstKey)

Get all the second level keys stored under the given first level key.

Parameters:

firstKey - the first level key.

Returns:

all second level keys for a first level key.

getValuesBySecondKey

public java.util.List<V> getValuesBySecondKey(K2 secondKey)

Get all values referenced by a second level key. Note: This method's complexity is linear in the number of first level keys.

Parameters:

secondKey - the second level key

Returns:

a new list of values referenced by the specified second level key

getValues

public java.util.List<V> getValues()

Get all values stored in the map.

Returns:

a new list of all values.

getSize

public int getSize()

Get size of the map.

Returns:

the number of values stored in this map.

isEmpty

public boolean isEmpty()

Check if the map is empty, i.e. no values are stored in it.

getSecondSize

public int getSecondSize(K1 key1)

Get the size of the (second) map stored for a first key.

Returns:

the size or 0 if the first level key wasn't found.

clear

public void clear()

Clear the whole map.

remove

public V remove(K1 key1,
                K2 key2)

Removes the value associated with the given key combination.

Returns:

previous value associated with specified keys, or null if there was no mapping for those keys. A null return can also indicate that the map previously associated null with the specified keys.

remove

public boolean remove(K1 key)

Remove all values stored under the given first level key.

Parameters:

key - first level key

Returns:

true if the given key was present in the map, false otherwise.

getSecondMap

public UnmodifiableMap<K2,V> getSecondMap(K1 key)

Returns the data stored under the given first-level key as an unmodifiable map or null if nothing is stored under that key.