Package com.gengoai.collection

Class HashMapIndex<TYPE>

java.lang.Object

com.gengoai.collection.HashMapIndex<TYPE>

Type Parameters:

TYPE - the type being indexed.

All Implemented Interfaces:

Index<TYPE>, Copyable<Index<TYPE>>, Serializable, Iterable<TYPE>

public class HashMapIndex<TYPE>
extends Object
implements Index<TYPE>, Serializable

An Index implementation that uses a combination of a HashMap and List.

Author:

David B. Bracewell

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
HashMapIndex()	Instantiates a new Hash map index.
HashMapIndex(@NonNull Iterable<TYPE> items)	Instantiates a new Hash map index.

Method Summary

Modifier and Type	Method	Description
int	add(TYPE item)	Adds an item to the index.
void	addAll(Iterable<TYPE> items)	Adds all the items in the iterable to the index
List<TYPE>	asList()	Retrieves an unmodifiable list view of the index
void	clear()	Clears the index
boolean	contains(TYPE item)	Determines if an item is in the index
Index<TYPE>	copy()	Makes a copy of this object.
boolean	equals(Object obj)
TYPE	get(int id)	Gets the item with the given id.
int	getId(TYPE item)	Gets the id of the item or -1 if it is not in the index.
int	hashCode()
boolean	isEmpty()	Determines if the index is empty
Set<TYPE>	itemSet()	Gets a set of the items in the Index
Iterator<TYPE>	iterator()
int	size()	The number of items in the index
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.gengoai.collection.Index

stream

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

HashMapIndex

public HashMapIndex()

Instantiates a new Hash map index.

HashMapIndex

public HashMapIndex(@NonNull
                    @NonNull Iterable<TYPE> items)

Instantiates a new Hash map index.

Parameters:

items - the items

Method Detail

add

public int add(TYPE item)

Description copied from interface: Index

Adds an item to the index. If the item is already in the index, the item's id is returned otherwise the newly generated id is returned.

Specified by:

add in interface Index<TYPE>

Parameters:

item - the item to add

Returns:

The id of the item

addAll

public void addAll(Iterable<TYPE> items)

Description copied from interface: Index

Adds all the items in the iterable to the index

Specified by:

addAll in interface Index<TYPE>

Parameters:

items - The items to add.

asList

public List<TYPE> asList()

Description copied from interface: Index

Retrieves an unmodifiable list view of the index

Specified by:

asList in interface Index<TYPE>

Returns:

an unmodifiable list view of the index

clear

public void clear()

Description copied from interface: Index

Clears the index

Specified by:

clear in interface Index<TYPE>

contains

public boolean contains(TYPE item)

Description copied from interface: Index

Determines if an item is in the index

Specified by:

contains in interface Index<TYPE>

Parameters:

item - The item

Returns:

True if the item is in the index, False if not

copy

public Index<TYPE> copy()

Description copied from interface: Copyable

Makes a copy of this object.

Specified by:

copy in interface Copyable<TYPE>

Returns:

A copy of this object.

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

get

public TYPE get(int id)

Description copied from interface: Index

Gets the item with the given id.

Specified by:

get in interface Index<TYPE>

Parameters:

id - The id

Returns:

The item associated with the id or null if there is none.

getId

public int getId(TYPE item)

Description copied from interface: Index

Gets the id of the item or -1 if it is not in the index.

Specified by:

getId in interface Index<TYPE>

Parameters:

item - The item whose id we want

Returns:

The id of the item or -1 if it is not in the index

hashCode

public int hashCode()

Overrides:

hashCode in class Object

isEmpty

public boolean isEmpty()

Description copied from interface: Index

Determines if the index is empty

Specified by:

isEmpty in interface Index<TYPE>

Returns:

True if there are no items in the index

itemSet

public Set<TYPE> itemSet()

Description copied from interface: Index

Gets a set of the items in the Index

Specified by:

itemSet in interface Index<TYPE>

Returns:

the set

iterator

public Iterator<TYPE> iterator()

Specified by:

iterator in interface Iterable<TYPE>

size

public int size()

Description copied from interface: Index

The number of items in the index

Specified by:

size in interface Index<TYPE>

Returns:

The number of items in the index

toString

public String toString()

Overrides:

toString in class Object