blbutil

Class IndexMap

java.lang.Object

blbutil.IndexMap

public class IndexMap
extends java.lang.Object

Class IndexMap is a map whose keys are a bounded set of non-negative integers and whose values are integers.

Class IndexMap supports a clear() method, but it does not support a remove() method.

Class IndexMap is not thread-safe.

Constructor Summary

Constructors

Constructor and Description
IndexMap(int maxKey, int nil) Creates a new instance of IndexMap whose nil() method will return the specified nil value.

Method Summary

Modifier and Type	Method and Description
void	clear() Removes all key-value pairs from the map.
int	enumeratedKey(int index) Returns the specified key in an enumeration of the keys in the map.
int	enumeratedValue(int index) Returns the value associated with the specified key in an enumeration of the keys in the map.
int	get(int key) Returns the value associated with the specified key, or this.nil() if the specified key is not contained in the map.
int	maxKey() Returns the maximum key.
int	nil() Returns the value that is returned by this.get() if a key has no assigned value.
int	put(int key, int value) Adds the specified key and value to the map.
int	size() Returns the number of key-value pairs in the map.
java.lang.String	toString() Returns a string representation of this.

Methods inherited from class java.lang.Object

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

Constructor Detail

IndexMap

public IndexMap(int maxKey,
                int nil)

Creates a new instance of IndexMap whose nil() method will return the specified nil value.

Parameters:

maxKey - the maximum key

nil - the value that will be returned by the instance's get() method if a key has no assigned value

Throws:

java.lang.IllegalArgumentException - if maxKey < 0

Method Detail

nil

public int nil()

Returns the value that is returned by this.get() if a key has no assigned value.

Returns:

the value that is returned by this.get() if a key has no assigned value

put

public int put(int key,
               int value)

Adds the specified key and value to the map. If the map contains a value for the specified key when the method is invoked, the old value is replaced by the specified value.

Parameters:

key - the key

value - the value

Returns:

the previous value associated with key, or this.nil() if no such previous value exists

Throws:

java.lang.IllegalArgumentException - if value == this.nil()

java.lang.IndexOutOfBoundsException - if key < 0 || key > this.maxKey()

get

public int get(int key)

Returns the value associated with the specified key, or this.nil() if the specified key is not contained in the map.

Parameters:

key - the key

Returns:

the value associated with the specified key, or this.nil() if the specified key is not contained in the map.

Throws:

java.lang.IndexOutOfBoundsException - if key < 0 || key > this.maxKey()

size

public int size()

Returns the number of key-value pairs in the map.

Returns:

the number of key-value pairs in the map

maxKey

public int maxKey()

Returns the maximum key.

Returns:

the maximum key

clear

public void clear()

Removes all key-value pairs from the map.

enumeratedKey

public int enumeratedKey(int index)

Returns the specified key in an enumeration of the keys in the map.

Parameters:

index - an index of an element in the enumeration

Returns:

the specified key in an enumeration of the keys-value pairs in the map

Throws:

java.lang.IndexOutOfBoundsException - if index < 0 || index >= this.size()

enumeratedValue

public int enumeratedValue(int index)

Returns the value associated with the specified key in an enumeration of the keys in the map. If (index >= 0 && index < this.size()), then the returned value will satisfy: this.get(this.enumeratedKey(index)==this.enumeratedValue(index).

Parameters:

index - an index of an element in the enumeration

Returns:

the value associated with the specified key in an enumeration of the keys in the map

Throws:

java.lang.IndexOutOfBoundsException - if index < 0 || index >= this.size()

toString

public java.lang.String toString()

Returns a string representation of this. The exact details of the representation are unspecified and subject to change.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of this.