AppleCommander/lib/ac-api/src/main/java/com/webcodepro/applecommander/util/Range.java

90 lines
2.4 KiB
Java

/*
* AppleCommander - An Apple ][ image utility.
* Copyright (C) 2002-2022 by Robert Greene and others
* robgreene at users.sourceforge.net
*
* This program 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 2 of the License, or (at your
* option) any later version.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.webcodepro.applecommander.util;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Represents a range of numbers with helper methods to put them together.
*/
public class Range {
private int first;
private int last;
public Range(int first, int last) {
if (first < last) {
this.first = first;
this.last = last;
}
else {
this.first = last;
this.last = first;
}
}
public int getFirst() {
return first;
}
public int getLast() {
return last;
}
public int size() {
return last - first + 1;
}
@Override
public String toString() {
if (first == last) {
return String.format("%d", first);
}
else {
return String.format("%d-%d", first, last);
}
}
public static List<Range> from(List<Integer> numbers) {
List<Range> ranges = new ArrayList<>();
Collections.sort(numbers);
int first = -1;
int last = -1;
for (int number : numbers) {
if (first == -1) {
first = last = number;
}
else if (number == last+1) {
last = number;
}
else {
ranges.add(new Range(first, last));
first = last = number;
}
}
if (first != -1) {
ranges.add(new Range(first, last));
}
return ranges;
}
}