com.aol.cyclops.matcher

Class Extractors

java.lang.Object

com.aol.cyclops.matcher.Extractors

public class Extractors
extends java.lang.Object

Generic extractors for use s pre and post data extractors.

Constructor Summary

Constructors

Constructor and Description
Extractors()

Method Summary

Modifier and Type	Method and Description
static <R> Extractor<java.lang.Iterable<R>,R>	at(int pos) Iterate to position and retieve value at position in an iterable data structure.
static <T,R> Extractor<T,R>	decompose()
static <R> Extractor<?,R>	first() Return element or first element in an Iterable.
static <R> Extractor<java.util.List<R>,R>	get(int pos) Look up element at position in a list
static <K,R> Extractor<java.util.Map<K,R>,R>	get(K key)
static <T,R> Extractor<T,R>	memoised(Extractor<T,R> extractor) An extractor that caches the extraction result
static <V1,V2> Extractor<java.lang.Iterable,Two<V1,V2>>	of(int v1, int v2) An extractor that will generte a Tuple2 with two values at the specified index.
static <T,R> void	registerDecompositionFunction(java.lang.Class<T> c, java.util.function.Function<T,R> f) Register decomposition function in standard hashmap Global mutable state - use with care
static <R> Extractor<R,R>	same()

Methods inherited from class java.lang.Object

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

Constructor Detail

Extractors

public Extractors()

Method Detail

registerDecompositionFunction

public static final <T,R> void registerDecompositionFunction(java.lang.Class<T> c,
                                                             java.util.function.Function<T,R> f)

Register decomposition function in standard hashmap Global mutable state - use with care

Parameters:

c - Class to decompose

f - Function to do decomposition

memoised

public static final <T,R> Extractor<T,R> memoised(Extractor<T,R> extractor)

An extractor that caches the extraction result

Parameters:

extractor - to memoise (cache result of)

Returns:

Memoised extractor

decompose

public static final <T,R> Extractor<T,R> decompose()

Returns:

Extractor that decomposes Case classes into iterables

of

public static final <V1,V2> Extractor<java.lang.Iterable,Two<V1,V2>> of(int v1,
                                                                        int v2)

An extractor that will generte a Tuple2 with two values at the specified index. Works on Iterable data structures.

Parameters:

v1 - position of the first element to extract

v2 - position of the second element to extract

Returns:

Tuple with 2 specified elements

first

public static final <R> Extractor<?,R> first()

Return element or first element in an Iterable.

Returns:

value

at

public static final <R> Extractor<java.lang.Iterable<R>,R> at(int pos)

Iterate to position and retieve value at position in an iterable data structure.

Parameters:

pos - Position to extract

Returns:

value

get

public static final <R> Extractor<java.util.List<R>,R> get(int pos)

Look up element at position in a list

Parameters:

pos - Position to extract element from

Returns:

Value at position

get

public static final <K,R> Extractor<java.util.Map<K,R>,R> get(K key)

Parameters:

key - Look up a value from a map

Returns:

Value for key specified

same

public static final <R> Extractor<R,R> same()

Returns:

identity extractor, returns same value