ANTLR Rule Evaluation Parser

The Rule Evaluation Parser is and auto-generated parser that uses ANTLR. It evaluates whether an array against an expression and returns true or false.

About ANTLR

ANTLR is an acronym for ANother Tool for Language Recognition which describes a generator of parsers, lexers, and TreeParsers and is developed by Terence Parr.

More documentation can be found here: https://www.antlr.org/

Function

The boolean evaluation works as follows:

The method RuleEvaluation.evaluate() takes an expression (also called "rule", e.g. 235 & (411 | 425), and evaluates it against a set of String, e.g. [48, 50, 56, 110, 111, 117, 118, 122]. The result of the evaluation can either be TRUE or FALSE.

Operators

Known operators for the rule evaluation are:

& = and
| = or
! = not
( = curly bracket left
) = curly bracket right

Example set of rules which can be evaluated:

! (48 & 50 & 56 & 110 & 111 & 117 & 118 & 122)
(351 & 362)
235 & (411 | 425)
701 & (351 & 362)
A21 | B23 | P43

How to build the project

Use the command mvn clean package to build the code from project source directory.

As an alternative, the commands mvn clean & mvn package can be run sequentially.

How to run

Unit tests

Use the command mvn test to run unit tests from project source directory.

The project

The rule can be evaluated like this RuleEvaluation.evaluate("! (48 & 50 & 56 & 110 & 111 & 117 & 118 & 122)", [48, 118, 122])

Build and run the TreeUI with IntelliJ

The TreeUI can be used to show a graphical representation of the expression. In the example below, the expression ! (48 & 50 & 56 & 110 & 111 & 117 & 118 & 122) is represented.

The easiest way run the TreeUI is to create a run configuration. You can use the rule "! (48 & 50 & 56 & 110 & 111 & 117 & 118 & 122)" as Program Arguments. It will start a Java application and print out the tree view of the expression.