caffeine

Replaces common java.util classes along with providing exciting new Data Structures:

• Tries
• Graphs
  • Finite Automaton
  • Weighted/Unweighted
• Sequences
  • Lazy evaluation
  • Functional style
• Monadic Pipelines
  • 'Streams' implementation with extra functions
• Pattern Matching and Guards
  • Along with configure factory method for matching any object.
• Tuples(0-12 arity), Try class, Lazy class
• Cons list and recursive Trees using pattern matching.

Aims

• The only imports from java.util will be to implement an Interface
• Where possible, use generics and implement Collection, Set, Map, List, Iterable etc.
• Always reduce complexity in algorithms
• Always refactor to minimise repeated code

Pipelines

• I have implemented and augmented the API for java.util.streams.Stream with Pipeline
  • Upgraded to match JDK 9 Streams API, with addition of more functional features:
  • zipping, cartesian product, matching, streaming optionals, pattern matching.
• Implemented as a linked list of Nodes that perform operations on values passed to them

Sequences

I have combined my implementation of Pipelines with additional functions for use in creating sequences

• Pick an algorithm style from
  • Recursive (New terms are generated based on the previous ones)
  • Non Recursive (Terms are only dependent on their index)
• Users can then:
  • Set the range of terms in scope
  • filter only terms that pass a predicate
  • take terms while a predicate holds true
  • drop terms while a predicate holds true
  • add and remove these conditions on the same Sequence instance
  • view individual terms
  • convert to a Pipeline for more options;

• Terms are memoised for higher performance over multiple iterations.

• Terms are generated lazily, i.e. only when they are requested.

  • This saves complexity, especially when using nested sequences

• Sequences are enhanced by:

  • SequenceOf - Contains plenty of standard sequences, such as natural numbers, integers, primes, ranges
  • Functions - Contains anonymous functions for use with the total() method
  • PredicateFor - Contains predicates for use with filtering or to add conditions

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Prerequisites

• Java 8

Usage

1. Clone this repository onto your system
2. Include the package com.bishabosha.caffeine in your build path

Replace standard library with:

• HashMap built on HashTable, implements java.util.Map
• HashTable implements java.util.Set and also provides term() method
• TreeMap built on SearchTree implements java.util.Map AVL balanced
• TreeSet built on SearchTree implements java.util.Set AVL balanced
• LinkedList implements java.util.Queue, java.util.Deque and java.util.List

Other Collections:

• SearchTree implements java.util.Collection AVL balanced BST, pre/post/in/level-order traversal
• TrieSet, implements java.util.Set Get word completions
• TrieMap, implements java.util.Map Get word completions and map values
• Graph extends RelationGraph, using RelationSet
  • f: node -> node
• WeightedGraph extends RelationGraph, using WeightedRelationSet
  • g: node -> (node, weight)

Base Classes to Save Code:

• AbstractBase provides basic toString(), hashCode() toArray() functions
• AbstractCollection implements java.util.Collection
• AbstractMap implements java.util.Map
• IncompleteSet implements java.util.Set

Introducing Sequences

• Sequence Generate generic sequences, with pipeline api for filtering with Predicates
• PredicateFor Special predicates for use with filtering
• SequenceOf Common sequences and for Project Euler
• Functions Common scalar functions to apply across the whole sequence

Special Included Classes

• FiniteAutomaton pattern matching with generics
  • union, intersection, kleenestar, complement, concatenation
• FiniteAutomatonFactory build automatons from words
• RelationSet implements Relation simple adjacency list
• WeightedRelationSet implements WeightedRelation extends Relation
  • f: node -> weight
  • g: weight -> {node}

Helper Classes

• IntLoop loop in a range, with a specific step, used with sequences
• Range value range with generics, used with sequences
• ScannerPlus For programming challenge practise, eliminate boilerplate typing!

Built With

• java