gistfile1.rb

# Playing with java topology suite in jruby
require 'java'
require 'rubygems'
require 'mvn:com.vividsolutions:jts'

java_import "com.vividsolutions.jts.geom.PrecisionModel"
java_import "com.vividsolutions.jts.geom.GeometryFactory"
java_import "com.vividsolutions.jts.geom.Coordinate"
java_import "com.vividsolutions.jts.geom.Point"
java_import "com.vividsolutions.jts.geom.LineString"
java_import "com.vividsolutions.jts.geom.LinearRing"
java_import "com.vividsolutions.jts.geom.Polygon"
java_import "com.vividsolutions.jts.geom.Coordinate"
java_import "com.vividsolutions.jts.geom.GeometryCollection"

pm = PrecisionModel.new PrecisionModel::FIXED
factory = GeometryFactory.new pm

p1 = factory.createPoint(Coordinate.new(0,0))
p2 = factory.createPoint(Coordinate.new(1,1))
p1.distance p2

linear_ring = factory.create_linear_ring(
  [
    Coordinate.new(0, 0), 
    Coordinate.new(10, 0), 
    Coordinate.new(10, 10),
    Coordinate.new(0, 10),
    Coordinate.new(0, 0)
  ].to_java('com.vividsolutions.jts.geom.Coordinate')
)
polygon1 = factory.create_polygon linear_ring, nil
polygon1.valid?
polygon1.area
polygon1.contains p1
polygon1.contains p2

linear_ring = factory.create_linear_ring(
  [
    Coordinate.new(5, 5),
    Coordinate.new(15, 5),
    Coordinate.new(15, 15),
    Coordinate.new(5, 15),
    Coordinate.new(5, 5)
  ].to_java('com.vividsolutions.jts.geom.Coordinate')
)
polygon2 = factory.create_polygon linear_ring, nil
polygon2.valid?
polygon2.area
polygon2.contains p1
polygon2.contains p2

polygon1.overlaps? polygon2
polygon1.covers? polygon2

polygon3 = polygon1.union polygon2
polygon3.get_coordinates
polygon3.area
polygon1.within polygon3
polygon2.within polygon3

polygon4 = polygon1.difference polygon2
polygon4.get_coordinates
polygon4.area
polygon4.within? polygon3