org.apache.mahout.math.map

Class AbstractByteLongMap

java.lang.Object

org.apache.mahout.math.PersistentObject

org.apache.mahout.math.set.AbstractSet

org.apache.mahout.math.map.AbstractByteLongMap

All Implemented Interfaces:

Serializable, Cloneable

Direct Known Subclasses:

OpenByteLongHashMap

public abstract class AbstractByteLongMap
extends AbstractSet

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.mahout.math.set.AbstractSet

DEFAULT_CAPACITY, DEFAULT_MAX_LOAD_FACTOR, DEFAULT_MIN_LOAD_FACTOR, distinct, highWaterMark, lowWaterMark, maxLoadFactor, minLoadFactor

Constructor Summary

Constructors

Constructor and Description
AbstractByteLongMap()

Method Summary

Methods

Modifier and Type	Method and Description
long	adjustOrPutValue(byte key, long newValue, long incrValue) Check the map for a key.
boolean	containsKey(byte key) Returns true if the receiver contains the specified key.
boolean	containsValue(long value) Returns true if the receiver contains the specified value.
AbstractByteLongMap	copy() Returns a deep copy of the receiver; uses clone() and casts the result.
boolean	equals(Object obj) Compares the specified object with this map for equality.
abstract boolean	forEachKey(ByteProcedure procedure) Applies a procedure to each key of the receiver, if any.
boolean	forEachPair(ByteLongProcedure procedure) Applies a procedure to each (key,value) pair of the receiver, if any.
abstract long	get(byte key) Returns the value associated with the specified key.
int	hashCode()
ByteArrayList	keys() Returns a list filled with all keys contained in the receiver.
void	keys(ByteArrayList list) Fills all keys contained in the receiver into the specified list.
void	keysSortedByValue(ByteArrayList keyList) Fills all keys sorted ascending by their associated value into the specified list.
void	pairsMatching(ByteLongProcedure condition, ByteArrayList keyList, LongArrayList valueList) Fills all pairs satisfying a given condition into the specified lists.
void	pairsSortedByKey(ByteArrayList keyList, LongArrayList valueList) Fills all keys and values sorted ascending by key into the specified lists.
void	pairsSortedByValue(ByteArrayList keyList, LongArrayList valueList) Fills all keys and values sorted ascending by value into the specified lists.
abstract boolean	put(byte key, long value) Associates the given key with the given value.
abstract boolean	removeKey(byte key) Removes the given key with its associated element from the receiver, if present.
String	toString() Returns a string representation of the receiver, containing the String representation of each key-value pair, sorted ascending by key.
String	toStringByValue() Returns a string representation of the receiver, containing the String representation of each key-value pair, sorted ascending by value.
LongArrayList	values() Returns a list filled with all values contained in the receiver.
void	values(LongArrayList list) Fills all values contained in the receiver into the specified list.

Methods inherited from class org.apache.mahout.math.set.AbstractSet

chooseGrowCapacity, chooseHighWaterMark, chooseLowWaterMark, chooseMeanCapacity, chooseShrinkCapacity, clear, ensureCapacity, equalsMindTheNull, isEmpty, nextPrime, setUp, size, trimToSize

Methods inherited from class org.apache.mahout.math.PersistentObject

clone

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractByteLongMap

public AbstractByteLongMap()

Method Detail

containsKey

public boolean containsKey(byte key)

Returns true if the receiver contains the specified key.

Returns:

true if the receiver contains the specified key.

containsValue

public boolean containsValue(long value)

Returns true if the receiver contains the specified value.

Returns:

true if the receiver contains the specified value.

copy

public AbstractByteLongMap copy()

Returns a deep copy of the receiver; uses clone() and casts the result.

Returns:

a deep copy of the receiver.

equals

public boolean equals(Object obj)

Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings. More formally, two maps m1 and m2 represent the same mappings iff

 m1.forEachPair(
    new ByteLongProcedure() {
      public boolean apply(byte key, long value) {
        return m2.containsKey(key) && m2.get(key) == value;
      }
    }
  )
 &&
 m2.forEachPair(
    new ByteLongProcedure() {
      public boolean apply(byte key, long value) {
        return m1.containsKey(key) && m1.get(key) == value;
      }
    }
  );
 

This implementation first checks if the specified object is this map; if so it returns true. Then, it checks if the specified object is a map whose size is identical to the size of this set; if not, it it returns false. If so, it applies the iteration as described above.

Overrides:

equals in class Object

Parameters:

obj - object to be compared for equality with this map.

Returns:

true if the specified object is equal to this map.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

forEachKey

public abstract boolean forEachKey(ByteProcedure procedure)

Applies a procedure to each key of the receiver, if any. Note: Iterates over the keys in no particular order. Subclasses can define a particular order, for example, "sorted by key". All methods which can be expressed in terms of this method (most methods can) must guarantee to use the same order defined by this method, even if it is no particular order. This is necessary so that, for example, methods keys and values will yield association pairs, not two uncorrelated lists.

Parameters:

procedure - the procedure to be applied. Stops iteration if the procedure returns false, otherwise continues.

Returns:

false if the procedure stopped before all keys where iterated over, true otherwise.

forEachPair

public boolean forEachPair(ByteLongProcedure procedure)

Applies a procedure to each (key,value) pair of the receiver, if any. Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

Parameters:

procedure - the procedure to be applied. Stops iteration if the procedure returns false, otherwise continues.

Returns:

false if the procedure stopped before all keys where iterated over, true otherwise.

get

public abstract long get(byte key)

Returns the value associated with the specified key. It is often a good idea to first check with containsKey(byte) whether the given key has a value associated or not, i.e. whether there exists an association for the given key or not.

Parameters:

key - the key to be searched for.

Returns:

the value associated with the specified key; 0 if no such key is present.

keys

public ByteArrayList keys()

Returns a list filled with all keys contained in the receiver. The returned list has a size that equals this.size(). Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

This method can be used to iterate over the keys of the receiver.

Returns:

the keys.

keys

public void keys(ByteArrayList list)

Fills all keys contained in the receiver into the specified list. Fills the list, starting at index 0. After this call returns the specified list has a new size that equals this.size(). Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

This method can be used to iterate over the keys of the receiver.

Parameters:

list - the list to be filled, can have any size.

keysSortedByValue

public void keysSortedByValue(ByteArrayList keyList)

Fills all keys sorted ascending by their associated value into the specified list. Fills into the list, starting at index 0. After this call returns the specified list has a new size that equals this.size(). Primary sort criterium is "value", secondary sort criterium is "key". This means that if any two values are equal, the smaller key comes first.

Example:
keys = (8,7,6), values = (1,2,2) --> keyList = (8,6,7)

Parameters:

keyList - the list to be filled, can have any size.

pairsMatching

public void pairsMatching(ByteLongProcedure condition,
                 ByteArrayList keyList,
                 LongArrayList valueList)

Fills all pairs satisfying a given condition into the specified lists. Fills into the lists, starting at index 0. After this call returns the specified lists both have a new size, the number of pairs satisfying the condition. Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

Example:

 IntIntProcedure condition = new IntIntProcedure() { // match even keys only
 public boolean apply(int key, int value) { return key%2==0; }
 }
 keys = (8,7,6), values = (1,2,2) --> keyList = (6,8), valueList = (2,1)
 

Parameters:

condition - the condition to be matched. Takes the current key as first and the current value as second argument.

keyList - the list to be filled with keys, can have any size.

valueList - the list to be filled with values, can have any size.

pairsSortedByKey

public void pairsSortedByKey(ByteArrayList keyList,
                    LongArrayList valueList)

Fills all keys and values sorted ascending by key into the specified lists. Fills into the lists, starting at index 0. After this call returns the specified lists both have a new size that equals this.size().

Example:
keys = (8,7,6), values = (1,2,2) --> keyList = (6,7,8), valueList = (2,2,1)

Parameters:

keyList - the list to be filled with keys, can have any size.

valueList - the list to be filled with values, can have any size.

pairsSortedByValue

public void pairsSortedByValue(ByteArrayList keyList,
                      LongArrayList valueList)

Fills all keys and values sorted ascending by value into the specified lists. Fills into the lists, starting at index 0. After this call returns the specified lists both have a new size that equals this.size(). Primary sort criterium is "value", secondary sort criterium is "key". This means that if any two values are equal, the smaller key comes first.

Example:
keys = (8,7,6), values = (1,2,2) --> keyList = (8,6,7), valueList = (1,2,2)

Parameters:

keyList - the list to be filled with keys, can have any size.

valueList - the list to be filled with values, can have any size.

put

public abstract boolean put(byte key,
          long value)

Associates the given key with the given value. Replaces any old (key,someOtherValue) association, if existing.

Parameters:

key - the key the value shall be associated with.

value - the value to be associated.

Returns:

true if the receiver did not already contain such a key; false if the receiver did already contain such a key - the new value has now replaced the formerly associated value.

removeKey

public abstract boolean removeKey(byte key)

Removes the given key with its associated element from the receiver, if present.

Parameters:

key - the key to be removed from the receiver.

Returns:

true if the receiver contained the specified key, false otherwise.

toString

public String toString()

Returns a string representation of the receiver, containing the String representation of each key-value pair, sorted ascending by key.

Overrides:

toString in class Object

toStringByValue

public String toStringByValue()

Returns a string representation of the receiver, containing the String representation of each key-value pair, sorted ascending by value.

values

public LongArrayList values()

Returns a list filled with all values contained in the receiver. The returned list has a size that equals this.size(). Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

This method can be used to iterate over the values of the receiver.

Returns:

the values.

values

public void values(LongArrayList list)

Fills all values contained in the receiver into the specified list. Fills the list, starting at index 0. After this call returns the specified list has a new size that equals this.size(). Iteration order is guaranteed to be identical to the order used by method forEachKey(ByteProcedure).

This method can be used to iterate over the values of the receiver.

Parameters:

list - the list to be filled, can have any size.

adjustOrPutValue

public long adjustOrPutValue(byte key,
                    long newValue,
                    long incrValue)

Check the map for a key. If present, add an increment to the value. If absent, store a specified value.

Parameters:

key - the key.

newValue - the value to store if the key is not currently in the map.

incrValue - the value to be added to the current value in the map.