jrunx.util
Class OrderedHashMap

java.lang.Object
  |
  +--java.util.AbstractMap
        |
        +--java.util.HashMap
              |
              +--jrunx.util.OrderedHashMap

All Implemented Interfaces:

java.lang.Cloneable, java.util.Map, java.io.Serializable

public class OrderedHashMap

extends java.util.HashMap

Hashtable that maintains the order in which objects are inserted. This object is useful for enumerating through keys in the order that they were inserted.

See Also:

Serialized Form

Inner classes inherited from class java.util.Map

java.util.Map.Entry

Constructor Summary

OrderedHashMap()

Method Summary

void	clear() Clears this hashtable so that it contains no keys.
java.lang.Object	get(int index) Get the element at the specified index.
java.util.Iterator	iterator() Returns the ordered set of elements.
java.util.Iterator	keys() Returns the ordered set of keys.
java.lang.Object	put(java.lang.Object key, java.lang.Object value) Insert an object into the table using the specified key.
java.lang.Object	remove(java.lang.Object key) Remove the object associated with the specified key.

Methods inherited from class java.util.HashMap

clone, containsKey, containsValue, entrySet, get, isEmpty, keySet, putAll, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Detail

OrderedHashMap

public OrderedHashMap()

Method Detail

iterator

public java.util.Iterator iterator()

Returns the ordered set of elements. Elements are ordered by the insertion order of their keys. The top-most object is the oldest inserted element. The bottom-most object is the most recently inserted element. If an element has been hashed multiple times using different keys, then it will show up in the the enumeration once for each key.

get

public java.lang.Object get(int index)

Get the element at the specified index. Note: - this returns the element object, not the key.

Returns:

the element at the specified index.

keys

public java.util.Iterator keys()

Returns the ordered set of keys. Keys are ordered by their insertion order. The top-most object is the oldest inserted key. The bottom-most object is the most recently inserted key.

put

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

Insert an object into the table using the specified key. If this key already exists in the table, it will be removed and then reinserted at the bottom of the ordered list.

Overrides:

put in class java.util.HashMap

remove

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

Remove the object associated with the specified key.

Overrides:

remove in class java.util.HashMap

clear

public void clear()

Clears this hashtable so that it contains no keys.

Overrides:

clear in class java.util.HashMap