package ca.pfv.spmf.algorithms.sequentialpatterns.lapin;
import java.util.ArrayList;
import java.util.List;
/***
* This is an implementation of a pair of items used by the LAPIN-SPAM algorithm to
* represent a 2-IE-sequence and its list of positions in a sequence.
*
* The LAPIN-SPAM algorithm was originally described in this paper:
*
* Zhenlu Yang and Masrau Kitsuregawa. LAPIN-SPAM: An improved algorithm for mining sequential pattern
* In Proc. of Int'l Special Workshop on Databases For Next Generation Researchers (SWOD'05)
* in conjunction with ICDE'05, pp. 8-11, Tokyo, Japan, Apr. 2005.
*
* Copyright (c) 2008-2013 Philippe Fournier-Viger
*
* This file is part of the SPMF DATA MINING SOFTWARE
* (http://www.philippe-fournier-viger.com/spmf).
*
* SPMF is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* SPMF 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with SPMF. If not, see <http://www.gnu.org/licenses/>.
*/
public class PairWithList implements Comparable<PairWithList> {
/** the first item */
protected int item1;
/** the second item */
protected int item2;
/** the list of positions where this pair appears */
List<Short> listPositions;
/**
* Constructor
* @param item1 the first item
* @param item2 the second item
*/
PairWithList(int item1, int item2){
this.item1 = item1;
this.item2 = item2;
}
/**
* Initialize the list of positions (by default it is not created)
*/
void createPositionList() {
listPositions = new ArrayList<Short>();
}
/**
* Compare this pair with another pair.
* @pram o the other pair
* @return a value > 0, == 0 or <0 if this pair is larger, equal of smaller than the other pair
*/
public int compareTo(PairWithList o) {
int val = this.item1 - o.item1;
if(val == 0) {
val = this.item2 - o.item2;
}
return val;
}
/**
* Method to check if this pair is equal to another
* @param obj the other pair
* @return true if both pair represents the same pair of items
*/
public boolean equals(Object obj) {
PairWithList pair = (PairWithList) obj;
return pair.item1 == this.item1 && pair.item2 == this.item2;
}
}