org.apache.xmlgraphics.image.loader.util.Penalty Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: Penalty.java 1345683 2012-06-03 14:50:33Z gadams $ */
package org.apache.xmlgraphics.image.loader.util;
/**
* Immutable class representing a penalty value. It's valid value range is that of an
* {@link Integer}, but giving {@link Integer#MAX_VALUE} a special meaning: it means infinite
* penalty, i.e. a candidate with this penalty will be excluded from any choice.
*/
public final class Penalty {
public static final Penalty ZERO_PENALTY = new Penalty(0);
public static final Penalty INFINITE_PENALTY = new Penalty(Integer.MAX_VALUE);
private final int value;
/**
* Turns a penalty value into a penaly object.
* @param value the penalty value
* @return the penalty object
*/
public static Penalty toPenalty(int value) {
switch (value) {
case 0:
return ZERO_PENALTY;
case Integer.MAX_VALUE:
return INFINITE_PENALTY;
default:
return new Penalty(value);
}
}
private Penalty(int value) {
this.value = value;
}
/**
* Adds a penalty to this one and returns the combined penalty.
* @param value the penalty value to add
* @return the resulting penalty
*/
public Penalty add(Penalty value) {
return add(value.getValue());
}
/**
* Adds a penalty to this one and returns the combined penalty.
* @param value the penalty value to add
* @return the resulting penalty
*/
public Penalty add(int value) {
long p = (long)getValue() + value;
return toPenalty(truncate(p));
}
/**
* Returns the penalty value.
* @return the penalty value
*/
public int getValue() {
return this.value;
}
/**
* Indicates whether this is an infinite penalty, meaning that a solution with this penalty
* is effectively ineligible.
* @return true if this is an infinite penalty
*/
public boolean isInfinitePenalty() {
return (value == Integer.MAX_VALUE);
}
/** {@inheritDoc} */
public String toString() {
return "Penalty: " + (isInfinitePenalty() ? "INF" : Integer.toString(getValue()));
}
/**
* Truncates the long penalty value to an integer without sign side-effects.
* @param penalty the penalty value as a long
* @return the penalty value as an int
*/
public static int truncate(long penalty) {
penalty = Math.min(Integer.MAX_VALUE, penalty);
penalty = Math.max(Integer.MIN_VALUE, penalty);
return (int)penalty;
}
}