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/*
* Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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 General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package pkg1;
/*
* Example from JSR 201, which borrowed it from "Effective Java".
*/
/**
* Arithmetic operations.
*/
public abstract enum Operation {
/** Addition */
plus {
/** Add 'em up. */
double eval(double x, double y) { return x + y; }
},
minus {
double eval(double x, double y) { return x - y; }
},
times {
double eval(double x, double y) { return x * y; }
},
divided_by {
double eval(double x, double y) { return x / y; }
};
/**
* Perform arithmetic operation represented by this constant.
*/
abstract double eval(double x, double y);
}
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