Java BigDecimal getFloatingPoint(Console console, Function validator)

Description

get Floating Point

License

Open Source License

Declaration

static BigDecimal getFloatingPoint(Console console, Function<BigDecimal, Boolean> validator) 

Method Source Code

//package com.java2s;
/*/* w  w w.j  a v  a2  s.c o  m*/
 * Copyright (C) 2016 Yadieet SA <yadieet@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.io.Console;
import java.math.BigDecimal;

import java.math.RoundingMode;

import java.util.function.Function;

public class Main {
    static BigDecimal getFloatingPoint(Console console, Function<BigDecimal, Boolean> validator) {
        if (validator == null)
            validator = value -> true;

        String answer;
        BigDecimal value;

        do {
            answer = readLine(console);
            try {
                value = stripAndOrRescale(new BigDecimal(answer));
                if (validator.apply(value))
                    break;
            } catch (NumberFormatException ignored) {
            }
        } while (true);

        return value;
    }

    static BigDecimal getFloatingPoint(Console console, BigDecimal minValue, BigDecimal maxValue) {
        if (minValue.compareTo(maxValue) > 0)
            throw new IllegalArgumentException("Invalid min-max value.");

        return getFloatingPoint(console, value -> value.compareTo(minValue) >= 0 && value.compareTo(maxValue) <= 0);
    }

    private static String readLine(Console console) {
        console.printf("> ");
        return console.readLine().trim();
    }

    private static BigDecimal stripAndOrRescale(BigDecimal value) {
        value = value.stripTrailingZeros();
        try {
            value.toBigIntegerExact();
            value = value.setScale(1, RoundingMode.UNNECESSARY);
        } catch (ArithmeticException ignored) {
        }
        return value;
    }
}

Related

1. getDigits(BigDecimal value)
2. getDistance(BigDecimal sourceLatitude, BigDecimal sourceLongitude, BigDecimal destLatitude, BigDecimal destLongitude)
3. getDividedBigDecimal(final int nDividend, final int nDivisor)
4. getDoubleBigDecimal(String amount, int afterDot)
5. getEndTimeByManDay(Date serviceStartTime, BigDecimal manDay)
6. getFormattedBigDecimal(BigDecimal value)
7. getFraction(BigDecimal b)
8. getFractionalPart(BigDecimal value)
9. getId(BigDecimal total, BigDecimal step)