Java BigInteger Parse getBigInteger(Console console, Function validator)

Description

get Big Integer

License

Open Source License

Declaration

static BigInteger getBigInteger(Console console, Function<BigInteger, Boolean> validator) 

Method Source Code

//package com.java2s;
/*/*from ww w . j a v  a 2 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.BigInteger;

import java.util.function.Function;

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

        String answer;
        BigInteger value;

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

        return value;
    }

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

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

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

Related

1. getBigInteger(byte[] payload, int offset, int length)
2. getBigInteger(Number number)
3. getBigInteger(Number value)
4. getBigInteger(String value)
5. getBigIntegerArrayFromByteArray(byte[] buf)