org.anchoranalysis.feature.calculate.part

Class CalculationPartMap<S,T extends FeatureInput,U,E extends Exception>

Object

CalculationPartMap<S,T,U,E>

Type Parameters:

S - result-type

T - feature input-type

U - key-type

E - an exception thrown if something goes wrong during the calculation

All Implemented Interfaces:

ResettableCalculation

Direct Known Subclasses:

CalculateIncrementalOperationMap

public abstract class CalculationPartMap<S,T extends FeatureInput,U,E extends Exception>
extends Object
implements ResettableCalculation

Similar to a CalculationPart but stores several evaluation results, differentiated by a key.

Author:

Owen Feehan

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	CalculationPartMap(int cacheSize) Creates for a particular cache-size.

Method Summary

Modifier and Type	Method and Description
abstract boolean	equals(Object other)
protected abstract S	execute(T input, U key) Calculates a result for a particular input and key.
S	getOrCalculate(T input, U key) Executes the operation and returns a result, either by doing the calculation, or retrieving a cached-result from a previous execution.
protected S	getOrNull(U key) Gets an existing result for the current input from the cache.
abstract int	hashCode()
protected boolean	hasKey(U key) Does a result exist for the current input, and a particular key?
void	invalidate() Invalidates the cache, removing any items already stored.
int	numberItemsCurrentlyStored() Number of items currently stored in cache.
protected void	put(U key, S result) Assigns a evaluation result to the cache for a particular key.

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CalculationPartMap

protected CalculationPartMap(int cacheSize)

Creates for a particular cache-size.

Parameters:

cacheSize - cache-size to use for the keys.

Method Detail

getOrCalculate

public S getOrCalculate(T input,
                        U key)
                 throws E extends Exception

Executes the operation and returns a result, either by doing the calculation, or retrieving a cached-result from a previous execution.

Parameters:

input - used to calculate a result, if there is no value already cached. Ignored if a result already exists.

key - the key, which determines if a result already exists or not.

Returns:

the result of the calculation.

Throws:

E - if the calculation cannot finish, for whatever reason.

E extends Exception

numberItemsCurrentlyStored

public int numberItemsCurrentlyStored()

Number of items currently stored in cache.

Returns:

then number of items.

invalidate

public void invalidate()

Invalidates the cache, removing any items already stored.

Specified by:

invalidate in interface ResettableCalculation

equals

public abstract boolean equals(Object other)

Overrides:

equals in class Object

hashCode

public abstract int hashCode()

Overrides:

hashCode in class Object

getOrNull

protected S getOrNull(U key)

Gets an existing result for the current input from the cache.

Parameters:

key - the key that identifies the existing result.

Returns:

a cached-result, or null if it doesn't exist.

hasKey

protected boolean hasKey(U key)

Does a result exist for the current input, and a particular key?

Parameters:

key - the key.

Returns:

true iff a result exists.

put

protected void put(U key,
                   S result)

Assigns a evaluation result to the cache for a particular key.

Parameters:

key - the key.

result - the result to assign.

execute

protected abstract S execute(T input,
                             U key)
                      throws E extends Exception

Calculates a result for a particular input and key.

Parameters:

input - the input.

key - the key.

Returns:

the evaluated result.

Throws:

E - if something goes wrong during calculation.

E extends Exception