0N/A/*
2362N/A * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
0N/A *
0N/A * This code is free software; you can redistribute it and/or modify it
0N/A * under the terms of the GNU General Public License version 2 only, as
2362N/A * published by the Free Software Foundation. Oracle designates this
0N/A * particular file as subject to the "Classpath" exception as provided
2362N/A * by Oracle in the LICENSE file that accompanied this code.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
0N/A *
2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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0N/A */
0N/A
0N/Apackage sun.tools.jstat;
0N/A
0N/Aimport java.util.*;
0N/A
0N/A
0N/A/**
0N/A * A typesafe enumeration for describing mathematical operators.
0N/A *
0N/A * @author Brian Doherty
0N/A * @since 1.5
0N/A */
0N/Apublic abstract class Operator {
0N/A
0N/A private static int nextOrdinal = 0;
0N/A private static HashMap<String, Operator> map = new HashMap<String, Operator>();
0N/A
0N/A private final String name;
0N/A private final int ordinal = nextOrdinal++;
0N/A
0N/A private Operator(String name) {
0N/A this.name = name;
0N/A map.put(name, this);
0N/A }
0N/A
0N/A protected abstract double eval(double x, double y);
0N/A
0N/A /* Operator '+' */
0N/A public static final Operator PLUS = new Operator("+") {
0N/A protected double eval(double x, double y) {
0N/A return x + y;
0N/A }
0N/A };
0N/A
0N/A /* Operator '-' */
0N/A public static final Operator MINUS = new Operator("-") {
0N/A protected double eval(double x, double y) {
0N/A return x - y;
0N/A }
0N/A };
0N/A
0N/A /* Operator '/' */
0N/A public static final Operator DIVIDE = new Operator("/") {
0N/A protected double eval(double x, double y) {
0N/A if (y == 0) {
0N/A return Double.NaN;
0N/A }
0N/A return x / y;
0N/A }
0N/A };
0N/A
0N/A /* Operator '*' */
0N/A public static final Operator MULTIPLY = new Operator("*") {
0N/A protected double eval(double x, double y) {
0N/A return x * y;
0N/A }
0N/A };
0N/A
0N/A /**
0N/A * Returns the string representation of this Operator object.
0N/A *
0N/A * @return the string representation of this Operator object
0N/A */
0N/A public String toString() {
0N/A return name;
0N/A }
0N/A
0N/A /**
0N/A * Maps a string to its corresponding Operator object.
0N/A *
0N/A * @param s an string to match against Operator objects.
0N/A * @return The Operator object matching the given string.
0N/A */
0N/A public static Operator toOperator(String s) {
0N/A return map.get(s);
0N/A }
0N/A
0N/A /**
0N/A * Returns an enumeration of the keys for this enumerated type
0N/A *
0N/A * @param s an string to match against Operator objects.
0N/A * @return The Operator object matching the given string.
0N/A */
0N/A protected static Set keySet() {
0N/A return map.keySet();
0N/A }
0N/A}