org.beandiff.core.LcsDiffEngine.scala Maven / Gradle / Ivy

Go to download
/**
 * Copyright (c) 2012-2013, Tomasz Kaczmarzyk.
 *
 * This file is part of BeanDiff.
 *
 * BeanDiff is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * BeanDiff is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with BeanDiff; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
package org.beandiff.core

import scala.collection.JavaConversions.asScalaBuffer
import org.beandiff.TypeDefs.JList
import org.beandiff.core.model.Diff
import org.beandiff.core.model.DeepDiff
import org.beandiff.core.model.Path
import org.beandiff.core.model.Path.EmptyPath
import org.beandiff.lcs.LcsCalc
import org.beandiff.support.CollectionSupport.convert
import org.beandiff.core.model.change.Deletion
import org.beandiff.core.model.change.Change
import org.beandiff.core.model.change.Deletion
import org.beandiff.core.model.change.Insertion
import org.beandiff.core.model.IndexProperty
import org.beandiff.support.ClassDictionary
import org.beandiff.equality.ObjectType

class LcsDiffEngine(
  private val delegate: DiffEngineCoordinator,
  val objTypes: ClassDictionary[ObjectType],
  private val lcsCalc: LcsCalc) extends DiffEngine {

  def calculateDiff(o1: Any, o2: Any) = {
    val xs = o1.asInstanceOf[JList]
    val ys = o2.asInstanceOf[JList]

    val lcs = lcsCalc.lcs(xs, ys)(objTypes)

    val deleted = xs.dropIndices(lcs.map(_.index1))
    val inserted = ys.dropIndices(lcs.map(_.index2))

    val dels = deleted.foldLeft(Diff(o1))( // TODO two similar and quite complex expressions, refactor
      (acc: Diff, elemWithIndex: (Any, Int)) => elemWithIndex match {
        case (elem, index) => acc.withChange(new Deletion(elem, index))
      })
    val delsAndInserts = inserted.foldLeft(dels)( // TODO two similar and quite complex expressions, refactor
      (acc: Diff, elemWithIndex: (Any, Int)) => elemWithIndex match {
        case (elem, index) => acc.withChange(new Insertion(elem, index))
      })

    lcs.foldLeft(delsAndInserts)(
      (accDiff, occurence) => {
        val ver1 = xs.get(occurence.index1)
        val ver2 = ys.get(occurence.index2)
        delegate.calculateDiff(accDiff, new IndexProperty(occurence.index1), ver1, ver2) // FIXME redundant when idInvestigator is full-diff-based?
      }
    )
  }
}