Package gov.nih.mipav.model.structures

Class CustomHashtable<V>

java.lang.Object

java.util.Dictionary<String,V>

java.util.Hashtable<String,V>

gov.nih.mipav.model.structures.CustomHashtable<V>

All Implemented Interfaces:

Serializable, Cloneable, Map<String,V>

public class CustomHashtable<V>
extends Hashtable<String,V>

CustomHashtable extends the Hashtable class and adds some methods for generating keys for new elements to the Hashtable. This is designed for storing the active images, but can also be used for image frames or any other list that needs to enforce unique keys.

Version:

0.1 November 16, 2001

Author:

Lynne M. Pusanik

See Also:

• Hashtable
• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private static final long	serialVersionUID	Use serialVersionUID for interoperability.

Constructor Summary

Constructors

Constructor	Description
CustomHashtable()	Constructs a new, empty hashtable with a default capacity and load factor, which is 0.75.
CustomHashtable(int capacity)	Constructs a new, empty hashtable with the specified initial capacity and default load factor, which is 0.75.
CustomHashtable(int capacity, float loadFactor)	Constructs a new, empty hashtable with the specified initial capacity and the specified load factor.
CustomHashtable(Map<String,V> t)	Constructs a new hashtable with the same mappings as the given Map.

Method Summary

Modifier and Type	Method	Description
protected String	appendKey(String key)	Starts with a key that already exists in the hashtable and appends integers to its toString().
String	makeUniqueKey(String key)	Returns a unique key string for the hashtable based on a given key string.

Methods inherited from class java.util.Hashtable

clear, clone, compute, computeIfAbsent, computeIfPresent, contains, containsKey, containsValue, elements, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keys, keySet, merge, put, putAll, putIfAbsent, rehash, remove, remove, replace, replace, replaceAll, size, toString, values

Methods inherited from class java.lang.Object

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

Field Details

serialVersionUID

private static final long serialVersionUID

Use serialVersionUID for interoperability.

See Also:

• Constant Field Values

Constructor Details

CustomHashtable

public CustomHashtable()

Constructs a new, empty hashtable with a default capacity and load factor, which is 0.75.

CustomHashtable

public CustomHashtable(Map<String,V> t)

Constructs a new hashtable with the same mappings as the given Map. The hashtable is created with a capacity of twice the number of entries in the given Map or 11 (whichever is greater), and a default load factor, which is 0.75.

Parameters:

t - Map to base the hashtable on

CustomHashtable

public CustomHashtable(int capacity)

Constructs a new, empty hashtable with the specified initial capacity and default load factor, which is 0.75.

Parameters:

capacity - initial capacity of the hashtable

CustomHashtable

public CustomHashtable(int capacity,
 float loadFactor)

Constructs a new, empty hashtable with the specified initial capacity and the specified load factor.

Parameters:

capacity - initial capacity of the hashtable

loadFactor - the load factor of the hashtable

Method Details

makeUniqueKey

public String makeUniqueKey(String key)

Returns a unique key string for the hashtable based on a given key string.

Parameters:

key - A string that we want to base a hashtable key on.

Returns:

A unique key, which should be used as an input to the

invalid reference

put()

method.

appendKey

protected String appendKey(String key)
                    throws NullPointerException

Starts with a key that already exists in the hashtable and appends integers to its toString(). Throws a NullPointer Exception if a unique key can't be found after appending all the integer values.

Parameters:

key - DOCUMENT ME!

Returns:

returns the newly formed key.

Throws:

NullPointerException - thrown when key cannot be appended to make a unique key.