Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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 {
    /**
     * Parses the string argument as if it was an int value and returns the
     * result. Throws NumberFormatException if the string does not represent an
     * int quantity.
     *
     * @param chars a string representation of an int quantity.
     * @return int the value represented by the argument
     * @throws NumberFormatException if the argument could not be parsed as an int quantity.
     */
    public static int parseInt(char[] chars) throws NumberFormatException {
        return parseInt(chars, 0, chars.length, 10);
    }

    /**
     * Parses a char array into an int.
     * @param chars the character array
     * @param offset The offset into the array
     * @param len The length
     * @return the int
     * @throws NumberFormatException if it can't parse
     */
    public static int parseInt(char[] chars, int offset, int len) throws NumberFormatException {
        return parseInt(chars, offset, len, 10);
    }

    /**
     * Parses the string argument as if it was an int value and returns the
     * result. Throws NumberFormatException if the string does not represent an
     * int quantity. The second argument specifies the radix to use when parsing
     * the value.
     *
     * @param chars a string representation of an int quantity.
     * @param radix the base to use for conversion.
     * @return int the value represented by the argument
     * @throws NumberFormatException if the argument could not be parsed as an int quantity.
     */
    public static int parseInt(char[] chars, int offset, int len, int radix) throws NumberFormatException {
        if (chars == null || radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) {
            throw new NumberFormatException();
        }
        int i = 0;
        if (len == 0) {
            throw new NumberFormatException("chars length is 0");
        }
        boolean negative = chars[offset + i] == '-';
        if (negative && ++i == len) {
            throw new NumberFormatException("can't convert to an int");
        }
        if (negative == true) {
            offset++;
            len--;
        }
        return parse(chars, offset, len, radix, negative);
    }

    private static int parse(char[] chars, int offset, int len, int radix, boolean negative)
            throws NumberFormatException {
        int max = Integer.MIN_VALUE / radix;
        int result = 0;
        for (int i = 0; i < len; i++) {
            int digit = Character.digit(chars[i + offset], radix);
            if (digit == -1) {
                throw new NumberFormatException("Unable to parse");
            }
            if (max > result) {
                throw new NumberFormatException("Unable to parse");
            }
            int next = result * radix - digit;
            if (next > result) {
                throw new NumberFormatException("Unable to parse");
            }
            result = next;
        }
        /*while (offset < len) {
            
        }*/
        if (!negative) {
            result = -result;
            if (result < 0) {
                throw new NumberFormatException("Unable to parse");
            }
        }
        return result;
    }
}