Java Integer Divide divideWithoutOverflow(int x, int y)

Description

Integer divide without overflow

License

Apache License

Exception

Parameter	Description
ArithmeticException	on overflow or divide-by-zero

Declaration

public static int divideWithoutOverflow(int x, int y) 

Method Source Code

//package com.java2s;
/*//from w w  w.  j a  va2 s  . co  m
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.
 */

public class Main {
    /**
     * Integer divide without overflow
     * @throws ArithmeticException on overflow or divide-by-zero
     */
    public static int divideWithoutOverflow(int x, int y) {
        if (x == Integer.MIN_VALUE && y == -1) {
            throw new ArithmeticException("integer overflow");
        }
        return x / y;
    }

    /**
     * Long divide without overflow
     * @throws ArithmeticException on overflow or divide-by-zero
     */
    public static long divideWithoutOverflow(long x, long y) {
        if (x == Long.MIN_VALUE && y == -1L) {
            throw new ArithmeticException("long overflow");
        }
        return x / y;
    }

    /**
     * Divides two floats but throws {@code ArithmeticException}
     * if the result overflows, or would create NaN from finite
     * inputs ({@code x == 0, y == 0})
     */
    public static float divideWithoutOverflow(float x, float y) {
        return checkNaNFloat(x, y, checkInfFloat(x, y, x / y));
    }

    /**
     * Divides two doubles but throws {@code ArithmeticException}
     * if the result overflows, or would create NaN from finite
     * inputs ({@code x == 0, y == 0})
     */
    public static double divideWithoutOverflow(double x, double y) {
        return checkNaNDouble(x, y, checkInfDouble(x, y, x / y));
    }

    /**
     * Checks for NaN, result is NaN but operands are finite
     * @throws ArithmeticException if overflow occurred
     */
    private static float checkNaNFloat(float x, float y, float z) {
        if (Float.isNaN(z)) {
            if (Float.isFinite(x) && Float.isFinite(y)) {
                throw new ArithmeticException("NaN");
            }
        }
        return z;
    }

    /**
     * Checks for overflow, result is infinite but operands are finite
     * @throws ArithmeticException if overflow occurred
     */
    private static float checkInfFloat(float x, float y, float z) {
        if (Float.isInfinite(z)) {
            if (Float.isFinite(x) && Float.isFinite(y)) {
                throw new ArithmeticException("float overflow");
            }
        }
        return z;
    }

    /**
     * Checks for NaN, result is NaN but operands are finite
     * @throws ArithmeticException if overflow occurred
     */
    private static double checkNaNDouble(double x, double y, double z) {
        if (Double.isNaN(z)) {
            if (Double.isFinite(x) && Double.isFinite(y)) {
                throw new ArithmeticException("NaN");
            }
        }
        return z;
    }

    /**
     * Checks for NaN, result is infinite but operands are finite
     * @throws ArithmeticException if overflow occurred
     */
    private static double checkInfDouble(double x, double y, double z) {
        if (Double.isInfinite(z)) {
            if (Double.isFinite(x) && Double.isFinite(y)) {
                throw new ArithmeticException("double overflow");
            }
        }
        return z;
    }
}

Related

1. divideStringWithInt(String strDividend, int divisor)
2. divideToCeil(int numerator, int denominator)
3. divideToInt(String address)
4. divideUnsigned(int dividend, int divisor)
5. divideWithCeilingRoundingMode(int p, int q)
6. division(int i_Divisor, int i_Dividend)
7. divisor(int a, int b)
8. divisor(int m, int n)
9. divisorMod(int a, int n)