prea.datastructure
Class DataMap<Key extends java.lang.Comparable<Key>,Val>

java.lang.Object
  prea.datastructure.DataMap<Key,Val>

All Implemented Interfaces:

java.lang.Iterable<Key>

public class DataMap<Key extends java.lang.Comparable<Key>,Val>
extends java.lang.Object
implements java.lang.Iterable<Key>

This is a class implementing HashMap-based data map. This data structure is used for implementing sparse vector and matrix.

Since:

2012. 3. 26

Version:

1.1

Author:

Joonseok Lee

Field Summary

private java.util.HashMap<Key,Val>

map Key-value mapping structure

Constructor Summary

DataMap()
Basic constructor without specifying the capacity.

DataMap(int capacity)
A constructor specifying the capacity.

Method Summary

boolean	contains(Key key) Check whether the map has a specific key inside it.
Val	get(Key key) Get a data value by the given key.
int	itemCount() Count the number of elements in the map.
java.util.Iterator<Key>	iterator() Get an iterator for the map.
void	put(Key key, Val value) Set a data value with the given key.
Val	remove(Key key) Remove a data element with the given key.

Methods inherited from class java.lang.Object

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

Field Detail

map

private java.util.HashMap<Key extends java.lang.Comparable<Key>,Val> map

Key-value mapping structure

Constructor Detail

DataMap

public DataMap()

Basic constructor without specifying the capacity.

DataMap

public DataMap(int capacity)

A constructor specifying the capacity. BE CAREFUL TO USE THIS! Never set the capacity too larger than actually needed. It will waste the memory space, reducing performance of your program.

Method Detail

get

public Val get(Key key)

Get a data value by the given key.

Parameters:

key - The key to search.

Returns:

The data value associated with the given key.

put

public void put(Key key,
                Val value)

Set a data value with the given key.

Parameters:

key - The key to set.

value - The data value associated with the given key.

remove

public Val remove(Key key)

Remove a data element with the given key.

Parameters:

key - The key to remove.

Returns:

The data value deleted with the given key.

contains

public boolean contains(Key key)

Check whether the map has a specific key inside it.

Parameters:

key - The key to search.

Returns:

true if the map has the given key, false otherwise.

iterator

public java.util.Iterator<Key> iterator()

Get an iterator for the map.

Specified by:

iterator in interface java.lang.Iterable<Key extends java.lang.Comparable<Key>>

Returns:

The Iterator instance for the map.

itemCount

public int itemCount()

Count the number of elements in the map.

Returns:

The number of items in the map.