de.unistuttgart.ims.commons

Class Counter<K>

java.lang.Object

java.util.AbstractMap<K,V>

java.util.HashMap<K,Integer>

de.unistuttgart.ims.commons.Counter<K>

Type Parameters:

K - The class we want to count

All Implemented Interfaces:

Serializable, Cloneable, Map<K,Integer>

public class Counter<K>
extends HashMap<K,Integer>

This class counts things, based on a HashMap with an Integer value.

Author:

reiterns

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
Counter()
Counter(Counter<K> c) Copy constructor

Method Summary

Modifier and Type	Method and Description
void	add(K k) Increases the value of k by 1.
void	add(K k, int i) Increases the value of k by i.
void	addAll(Collection<? extends K> arg) Increases the value of all elements in arg by 1.
static Counter<String>	fromString(Reader r) A static function that creates a Counter<String> object from a stream.
Integer	get(Object k)
int	getHighestCount() Returns the maximal number
Set<K>	getKeysWithMaxCount()
org.apache.commons.math3.util.Pair<Integer,Set<K>>	getMax() Returns a pair with the maximal value and all elements that have it.
org.apache.commons.math3.util.Pair<Integer,Set<K>>	getMin() Returns a pair with the maximal value and all elements that have it.
void	subtract(K k) Decreases the value of k by 1.
void	subtractAll(Collection<? extends K> arg) Decreases the value of all elements in arg by 1.

Methods inherited from class java.util.HashMap

clear, clone, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, forEach, getOrDefault, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, 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

Counter

public Counter()

Counter

public Counter(Counter<K> c)

Copy constructor

Parameters:

c - A counter object to copy from

Method Detail

add

public void add(K k)

Increases the value of k by 1. If k was not in the map before, it will be afterwards.

Parameters:

k - the object we count

add

public void add(K k,
                int i)

Increases the value of k by i. Adds k to the map if necessary.

Parameters:

k - The countee

i - The amount

subtract

public void subtract(K k)

Decreases the value of k by 1.

Parameters:

k - the countee

addAll

public void addAll(Collection<? extends K> arg)

Increases the value of all elements in arg by 1.

Parameters:

arg - a collection of countees

subtractAll

public void subtractAll(Collection<? extends K> arg)

Decreases the value of all elements in arg by 1.

Parameters:

arg - a collection of countees

getMax

public org.apache.commons.math3.util.Pair<Integer,Set<K>> getMax()

Returns a pair with the maximal value and all elements that have it.

Returns:

a pair

getMin

public org.apache.commons.math3.util.Pair<Integer,Set<K>> getMin()

Returns a pair with the maximal value and all elements that have it.

Returns:

a pair

getHighestCount

public int getHighestCount()

Returns the maximal number

getKeysWithMaxCount

public Set<K> getKeysWithMaxCount()

Returns:

a set containing all things with the maximal number

get

public Integer get(Object k)

Specified by:

get in interface Map<K,Integer>

Overrides:

get in class HashMap<K,Integer>

fromString

public static Counter<String> fromString(Reader r)
                                  throws IOException

A static function that creates a Counter<String> object from a stream. The function assumes that string and count are separated by a tab character.

Parameters:

r - The reader object from which we read.

Returns:

A new Counter object.

Throws:

IOException - thrown in case of IO exceptions