package it.unimi.dsi.util;
/*
* DSI utilities
*
* Copyright (C) 2003-2009 Paolo Boldi and Sebastiano Vigna
*
* This library 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 2.1 of the License, or (at your option)
* any later version.
*
* This library 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
import java.util.Comparator;
/** A class providing static methods and objects that do useful things with intervals.
*
* @see Interval
*/
public class Intervals {
private Intervals() {}
public final static Interval[] EMPTY_ARRAY = {};
/** An empty (singleton) interval. */
public final static Interval EMPTY_INTERVAL = new Interval( 1, 0 );
/** A singleton located at −&infty;. */
public final static Interval MINUS_INFINITY = new Interval( Integer.MIN_VALUE, Integer.MIN_VALUE );
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>'] iff
* the first interval starts before or prolongs the second one, that is,
* iff <var>a</var> < <var>a</var>' or <var>a</var>=<var>a</var>' and <var>b</var>' < <var>b</var>.
*/
public final static Comparator<Interval> STARTS_BEFORE_OR_PROLONGS = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.left != i2.left ) return i1.left < i2.left ? -1 : 1;
if ( i1.right != i2.right ) return i2.right < i1.right ? -1 : 1;
return 0;
}
};
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>'] iff
* the first interval ends before or is a suffix of the second one, that is,
* iff <var>b</var> < <var>b</var>' or <var>b</var>=<var>b</var>' and <var>a</var>' < <var>a</var>.
*/
public final static Comparator<Interval> ENDS_BEFORE_OR_IS_SUFFIX = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.right != i2.right ) return i1.right < i2.right ? -1 : 1;
if ( i1.left != i2.left ) return i2.left < i1.left ? -1 : 1;
return 0;
}
};
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>']
* iff the first interval starts <em>after</em> the second one, that is,
* iff <var>a</var>' < <var>a</var>.
*/
public final static Comparator<Interval> STARTS_AFTER = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.left != i2.left ) return i2.left < i1.left ? -1 : 1;
return 0;
}
};
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>']
* iff the first interval starts <em>before</em> the second one, that is,
* iff <var>a</var>' > <var>a</var>.
*/
public final static Comparator<Interval> STARTS_BEFORE = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.left != i2.left ) return i2.left < i1.left ? 1 : -1;
return 0;
}
};
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>']
* iff the first interval ends <em>after</em> the second one, that is,
* iff <var>b</var>' < <var>b</var>.
*/
public final static Comparator<Interval> ENDS_AFTER = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.right != i2.right ) return i2.right < i1.right ? -1 : 1;
return 0;
}
};
/** A comparator between intervals defined as follows:
* [<var>a</var>..<var>b</var>] is less than [<var>a</var>'..<var>b</var>']
* iff the first interval ends <em>before</em> the second one, that is,
* iff <var>b</var>' > <var>b</var>.
*/
public final static Comparator<Interval> ENDS_BEFORE = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
if ( i1.right != i2.right ) return i2.right < i1.right ? 1 : -1;
return 0;
}
};
/** A comparator between intervals based on their length. */
public final static Comparator<Interval> LENGTH_COMPARATOR = new Comparator<Interval>() {
public int compare( final Interval i1, final Interval i2 ) {
return i1.length() - i2.length();
}
};
}