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/*
* LingPipe v. 4.1.0
* Copyright (C) 2003-2011 Alias-i
*
* This program is licensed under the Alias-i Royalty Free License
* Version 1 WITHOUT ANY WARRANTY, without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the Alias-i
* Royalty Free License Version 1 for more details.
*
* You should have received a copy of the Alias-i Royalty Free License
* Version 1 along with this program; if not, visit
* http://alias-i.com/lingpipe/licenses/lingpipe-license-1.txt or contact
* Alias-i, Inc. at 181 North 11th Street, Suite 401, Brooklyn, NY 11211,
* +1 (718) 290-9170.
*/
package com.aliasi.util;
import java.util.Comparator;
/**
* A ScoredObject provides an implementation of the
* Scored interface with an attached object. Scored
* objects are immutable and identity is reference. The object
* returned by the getter {@link #getObject()} is the actual object
* stored, so changes to it will affect the scored object of which it
* is a part.
*
* @author Bob Carpenter
* @version 3.8.3
* @since LingPipe2.0
* @param the type of object that is scored
*/
public class ScoredObject implements Scored {
private final E mObj;
private final double mScore;
/**
* Construct a scored object from the specified object
* and score.
*
* @param obj Object for the constructed scored object.
* @param score Score for the constructed scored object.
*/
public ScoredObject(E obj, double score) {
mObj = obj;
mScore = score;
}
/**
* Returns the object attached to this scored object.
*
* @return The object attached to this scored object.
*/
public E getObject() {
return mObj;
}
/**
* Returns the score for this scored object.
*
* @return The score for this scored object.
*/
public double score() {
return mScore;
}
/**
* Returns a string-based representation of this object consisting
* of the score followed by a colon (':'), followed
* by the object converted to a string.
*
* @return The string-based representation of this object.
*/
@Override
public String toString() {
return mScore + ":" + getObject();
}
/**
* Returns true if the specified object is
* a scored object with an object equal to this object's
* and equal scores.
*
* @param that Object to compare to this scored object.
* @return true if the object is a scored object
* equal to this one.
*/
@Override
@SuppressWarnings("rawtypes") // required for instanceof
public boolean equals(Object that) {
if (!(that instanceof ScoredObject))
return false;
ScoredObject thatSo = (ScoredObject) that;
return mObj.equals(thatSo.mObj)
&& mScore == thatSo.mScore;
}
/**
* Returns a comparator that sorts in ascending order of score.
*
* This comparator may not be consistent with equality on
* the objects being compared, as it only depends on the score.
*
The returned comparator may be used as the priority ordering
* for a priority queue of objects sorted by score. It may also
* be passed to {@link
* java.util.Arrays#sort(Object[],Comparator)}.
*
*
This implementation is a singleton -- the same comparator
* is used for all instances.
*
* @return The ascending score comparator.
* @param the type of scored objects being compared
*/
public static Comparator comparator() {
@SuppressWarnings({"unchecked","deprecation"})
Comparator result = (Comparator) SCORE_COMPARATOR;
return result;
}
/**
* Returns a comparator that sorts in descending order of score.
* This is just the inverse ordering of {@link #comparator()}; see
* that method's documentation for more details.
*
* @return The descending score comparator.
* @param the type of scored objects being compared
*/
public static Comparator reverseComparator() {
@SuppressWarnings({"unchecked", "deprecation"})
Comparator result = (Comparator) REVERSE_SCORE_COMPARATOR;
return result;
}
static final Comparator REVERSE_SCORE_COMPARATOR
= new ScoredObject.ReverseScoredComparator();
static final Comparator SCORE_COMPARATOR
= new ScoredObject.ScoredComparator();
// package privates can't go in interface, so park them here
static class ScoredComparator implements Comparator {
public int compare(Scored obj1, Scored obj2) {
return (obj1.score() > obj2.score())
? 1
: ( (obj1.score() < obj2.score())
? -1
: 0 );
}
};
static class ReverseScoredComparator
implements Comparator {
public int compare(Scored obj1, Scored obj2) {
return (obj1.score() > obj2.score())
? -1
: ( (obj1.score() < obj2.score())
? 1
: 0 );
}
};
}