DateRange.java

package mf;

/*Generated by MPS */

import java.util.Date;
import java.util.Arrays;

public class DateRange implements Comparable {
  public static DateRange EMPTY = new DateRange(new MfDate(2000, 4, 1), new MfDate(2000, 1, 1));
  private MfDate myStart;
  private MfDate myEnd;
  public DateRange(Date start, Date end) {
    this(new MfDate(start), new MfDate(end));
  }
  public DateRange(MfDate start, MfDate end) {
    this.myStart = start;
    this.myEnd = end;
  }
  public MfDate end() {
    return myEnd;
  }
  public MfDate start() {
    return myStart;
  }
  @Override
  public String toString() {
    if (isEmpty()) {
      return "Empty Date Range";
    }
    return myStart.toString() + " - " + myEnd.toString();
  }
  public boolean isEmpty() {
    return myStart.after(myEnd);
  }
  public boolean includes(MfDate arg) {
    return !(arg.before(myStart)) && !(arg.after(myEnd));
  }
  @Override
  public boolean equals(Object arg) {
    if (!((arg instanceof DateRange))) {
      return false;
    }
    DateRange other = (DateRange) arg;
    return myStart.equals(other.myStart) && myEnd.equals(other.myEnd);
  }
  @Override
  public int hashCode() {
    return myStart.hashCode();
  }
  public boolean overlaps(DateRange arg) {
    return arg.includes(myStart) || arg.includes(myEnd) || this.includes(arg);
  }
  public boolean includes(DateRange arg) {
    return this.includes(arg.myStart) && this.includes(arg.myEnd);
  }
  public DateRange gap(DateRange arg) {
    if (this.overlaps(arg)) {
      return EMPTY;
    }
    DateRange lower;
    DateRange higher;
    if (this.compareTo(arg) < 0) {
      lower = this;
      higher = arg;
    } else {
      lower = arg;
      higher = this;
    }
    return new DateRange(lower.myEnd.addDays(1), higher.myStart.addDays(-1));
  }
  @Override
  public int compareTo(Object arg) {
    DateRange other = (DateRange) arg;
    if (!(myStart.equals(other.myStart))) {
      return myStart.compareTo(other.myStart);
    }
    return myEnd.compareTo(other.myEnd);
  }
  public boolean abuts(DateRange arg) {
    return !(this.overlaps(arg)) && this.gap(arg).isEmpty();
  }
  public boolean partitionedBy(DateRange[] args) {
    if (!(DateRange.isContiguous(args))) {
      return false;
    }
    return this.equals(DateRange.combination(args));
  }
  public static DateRange upTo(MfDate end) {
    return new DateRange(MfDate.PAST, end);
  }
  public static DateRange startingOn(MfDate start) {
    return new DateRange(start, MfDate.FUTURE);
  }
  public static DateRange combination(DateRange[] args) {
    Arrays.sort(args);
    if (!(DateRange.isContiguous(args))) {
      throw new IllegalArgumentException("Unable to combine date ranges");
    }
    return new DateRange(args[0].myStart, args[args.length - 1].myEnd);
  }
  public static boolean isContiguous(DateRange[] args) {
    Arrays.sort(args);
    for (int i = 0; i < args.length - 1; i++) {
      if (!(args[i].abuts(args[i + 1]))) {
        return false;
      }
    }
    return true;
  }
}