    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.lang3.math;
    018
    019import java.lang.reflect.Array;
    020import java.math.BigDecimal;
    021import java.math.BigInteger;
    022import java.math.RoundingMode;
    023import java.util.Objects;
    024
    025import org.apache.commons.lang3.StringUtils;
    026import org.apache.commons.lang3.Validate;
    027
    028/**
    029 * Provides extra functionality for Java Number classes.
    030 *
    031 * @since 2.0
    032 */
    033public class NumberUtils {
    034
    035    /** Reusable Long constant for zero. */
    036    public static final Long LONG_ZERO = Long.valueOf(0L);
    037    /** Reusable Long constant for one. */
    038    public static final Long LONG_ONE = Long.valueOf(1L);
    039    /** Reusable Long constant for minus one. */
    040    public static final Long LONG_MINUS_ONE = Long.valueOf(-1L);
    041    /** Reusable Integer constant for zero. */
    042    public static final Integer INTEGER_ZERO = Integer.valueOf(0);
    043    /** Reusable Integer constant for one. */
    044    public static final Integer INTEGER_ONE = Integer.valueOf(1);
    045    /** Reusable Integer constant for two */
    046    public static final Integer INTEGER_TWO = Integer.valueOf(2);
    047    /** Reusable Integer constant for minus one. */
    048    public static final Integer INTEGER_MINUS_ONE = Integer.valueOf(-1);
    049    /** Reusable Short constant for zero. */
    050    public static final Short SHORT_ZERO = Short.valueOf((short) 0);
    051    /** Reusable Short constant for one. */
    052    public static final Short SHORT_ONE = Short.valueOf((short) 1);
    053    /** Reusable Short constant for minus one. */
    054    public static final Short SHORT_MINUS_ONE = Short.valueOf((short) -1);
    055    /** Reusable Byte constant for zero. */
    056    public static final Byte BYTE_ZERO = Byte.valueOf((byte) 0);
    057    /** Reusable Byte constant for one. */
    058    public static final Byte BYTE_ONE = Byte.valueOf((byte) 1);
    059    /** Reusable Byte constant for minus one. */
    060    public static final Byte BYTE_MINUS_ONE = Byte.valueOf((byte) -1);
    061    /** Reusable Double constant for zero. */
    062    public static final Double DOUBLE_ZERO = Double.valueOf(0.0d);
    063    /** Reusable Double constant for one. */
    064    public static final Double DOUBLE_ONE = Double.valueOf(1.0d);
    065    /** Reusable Double constant for minus one. */
    066    public static final Double DOUBLE_MINUS_ONE = Double.valueOf(-1.0d);
    067    /** Reusable Float constant for zero. */
    068    public static final Float FLOAT_ZERO = Float.valueOf(0.0f);
    069    /** Reusable Float constant for one. */
    070    public static final Float FLOAT_ONE = Float.valueOf(1.0f);
    071    /** Reusable Float constant for minus one. */
    072    public static final Float FLOAT_MINUS_ONE = Float.valueOf(-1.0f);
    073
    074    /**
    075     * {@link Integer#MAX_VALUE} as a {@link Long}.
    076     *
    077     * @since 3.12.0
    078     */
    079    public static final Long LONG_INT_MAX_VALUE = Long.valueOf(Integer.MAX_VALUE);
    080
    081    /**
    082     * {@link Integer#MIN_VALUE} as a {@link Long}.
    083     *
    084     * @since 3.12.0
    085     */
    086    public static final Long LONG_INT_MIN_VALUE = Long.valueOf(Integer.MIN_VALUE);
    087
    088
    089    /**
    090     * Compares two {@code byte} values numerically. This is the same functionality as provided in Java 7.
    091     *
    092     * @param x the first {@code byte} to compare
    093     * @param y the second {@code byte} to compare
    094     * @return the value {@code 0} if {@code x == y};
    095     *         a value less than {@code 0} if {@code x < y}; and
    096     *         a value greater than {@code 0} if {@code x > y}
    097     * @since 3.4
    098     */
    099    public static int compare(final byte x, final byte y) {
    100        return x - y;
    101    }
    102
    103    /**
    104     * Compares two {@code int} values numerically. This is the same functionality as provided in Java 7.
    105     *
    106     * @param x the first {@code int} to compare
    107     * @param y the second {@code int} to compare
    108     * @return the value {@code 0} if {@code x == y};
    109     *         a value less than {@code 0} if {@code x < y}; and
    110     *         a value greater than {@code 0} if {@code x > y}
    111     * @since 3.4
    112     */
    113    public static int compare(final int x, final int y) {
    114        if (x == y) {
    115            return 0;
    116        }
    117        return x < y ? -1 : 1;
    118    }
    119
    120    /**
    121     * Compares to {@code long} values numerically. This is the same functionality as provided in Java 7.
    122     *
    123     * @param x the first {@code long} to compare
    124     * @param y the second {@code long} to compare
    125     * @return the value {@code 0} if {@code x == y};
    126     *         a value less than {@code 0} if {@code x < y}; and
    127     *         a value greater than {@code 0} if {@code x > y}
    128     * @since 3.4
    129     */
    130    public static int compare(final long x, final long y) {
    131        if (x == y) {
    132            return 0;
    133        }
    134        return x < y ? -1 : 1;
    135    }
    136
    137    /**
    138     * Compares to {@code short} values numerically. This is the same functionality as provided in Java 7.
    139     *
    140     * @param x the first {@code short} to compare
    141     * @param y the second {@code short} to compare
    142     * @return the value {@code 0} if {@code x == y};
    143     *         a value less than {@code 0} if {@code x < y}; and
    144     *         a value greater than {@code 0} if {@code x > y}
    145     * @since 3.4
    146     */
    147    public static int compare(final short x, final short y) {
    148        if (x == y) {
    149            return 0;
    150        }
    151        return x < y ? -1 : 1;
    152    }
    153
    154    /**
    155     * Convert a {@link String} to a {@link BigDecimal}.
    156     *
    157     * <p>Returns {@code null} if the string is {@code null}.</p>
    158     *
    159     * @param str  a {@link String} to convert, may be null
    160     * @return converted {@link BigDecimal} (or null if the input is null)
    161     * @throws NumberFormatException if the value cannot be converted
    162     */
    163    public static BigDecimal createBigDecimal(final String str) {
    164        if (str == null) {
    165            return null;
    166        }
    167        // handle JDK1.3.1 bug where "" throws IndexOutOfBoundsException
    168        if (StringUtils.isBlank(str)) {
    169            throw new NumberFormatException("A blank string is not a valid number");
    170        }
    171        return new BigDecimal(str);
    172    }
    173
    174    /**
    175     * Convert a {@link String} to a {@link BigInteger};
    176     * since 3.2 it handles hexadecimal (0x or #) and octal (0) notations.
    177     *
    178     * <p>Returns {@code null} if the string is {@code null}.</p>
    179     *
    180     * @param str  a {@link String} to convert, may be null
    181     * @return converted {@link BigInteger} (or null if the input is null)
    182     * @throws NumberFormatException if the value cannot be converted
    183     */
    184    public static BigInteger createBigInteger(final String str) {
    185        if (str == null) {
    186            return null;
    187        }
    188        if (str.isEmpty()) {
    189            throw new NumberFormatException("An empty string is not a valid number");
    190        }
    191        int pos = 0; // offset within string
    192        int radix = 10;
    193        boolean negate = false; // need to negate later?
    194        final char char0 = str.charAt(0);
    195        if (char0 == '-') {
    196            negate = true;
    197            pos = 1;
    198        } else if (char0 == '+') {
    199            pos = 1;
    200        }
    201        if (str.startsWith("0x", pos) || str.startsWith("0X", pos)) { // hex
    202            radix = 16;
    203            pos += 2;
    204        } else if (str.startsWith("#", pos)) { // alternative hex (allowed by Long/Integer)
    205            radix = 16;
    206            pos++;
    207        } else if (str.startsWith("0", pos) && str.length() > pos + 1) { // octal; so long as there are additional digits
    208            radix = 8;
    209            pos++;
    210        } // default is to treat as decimal
    211
    212        final BigInteger value = new BigInteger(str.substring(pos), radix);
    213        return negate ? value.negate() : value;
    214    }
    215
    216    /**
    217     * Convert a {@link String} to a {@link Double}.
    218     *
    219     * <p>Returns {@code null} if the string is {@code null}.</p>
    220     *
    221     * @param str  a {@link String} to convert, may be null
    222     * @return converted {@link Double} (or null if the input is null)
    223     * @throws NumberFormatException if the value cannot be converted
    224     */
    225    public static Double createDouble(final String str) {
    226        if (str == null) {
    227            return null;
    228        }
    229        return Double.valueOf(str);
    230    }
    231
    232    /**
    233     * Convert a {@link String} to a {@link Float}.
    234     *
    235     * <p>Returns {@code null} if the string is {@code null}.</p>
    236     *
    237     * @param str  a {@link String} to convert, may be null
    238     * @return converted {@link Float} (or null if the input is null)
    239     * @throws NumberFormatException if the value cannot be converted
    240     */
    241    public static Float createFloat(final String str) {
    242        if (str == null) {
    243            return null;
    244        }
    245        return Float.valueOf(str);
    246    }
    247
    248    /**
    249     * Convert a {@link String} to a {@link Integer}, handling
    250     * hexadecimal (0xhhhh) and octal (0dddd) notations.
    251     * N.B. a leading zero means octal; spaces are not trimmed.
    252     *
    253     * <p>Returns {@code null} if the string is {@code null}.</p>
    254     *
    255     * @param str  a {@link String} to convert, may be null
    256     * @return converted {@link Integer} (or null if the input is null)
    257     * @throws NumberFormatException if the value cannot be converted
    258     */
    259    public static Integer createInteger(final String str) {
    260        if (str == null) {
    261            return null;
    262        }
    263        // decode() handles 0xAABD and 0777 (hex and octal) as well.
    264        return Integer.decode(str);
    265    }
    266
    267    /**
    268     * Convert a {@link String} to a {@link Long};
    269     * since 3.1 it handles hexadecimal (0Xhhhh) and octal (0ddd) notations.
    270     * N.B. a leading zero means octal; spaces are not trimmed.
    271     *
    272     * <p>Returns {@code null} if the string is {@code null}.</p>
    273     *
    274     * @param str  a {@link String} to convert, may be null
    275     * @return converted {@link Long} (or null if the input is null)
    276     * @throws NumberFormatException if the value cannot be converted
    277     */
    278    public static Long createLong(final String str) {
    279        if (str == null) {
    280            return null;
    281        }
    282        return Long.decode(str);
    283    }
    284
    285    /**
    286     * Turns a string value into a java.lang.Number.
    287     *
    288     * <p>If the string starts with {@code 0x} or {@code -0x} (lower or upper case) or {@code #} or {@code -#}, it
    289     * will be interpreted as a hexadecimal Integer - or Long, if the number of digits after the
    290     * prefix is more than 8 - or BigInteger if there are more than 16 digits.
    291     * </p>
    292     * <p>Then, the value is examined for a type qualifier on the end, i.e. one of
    293     * {@code 'f', 'F', 'd', 'D', 'l', 'L'}.  If it is found, it starts
    294     * trying to create successively larger types from the type specified
    295     * until one is found that can represent the value.</p>
    296     *
    297     * <p>If a type specifier is not found, it will check for a decimal point
    298     * and then try successively larger types from {@link Integer} to
    299     * {@link BigInteger} and from {@link Float} to
    300     * {@link BigDecimal}.</p>
    301     *
    302     * <p>
    303     * Integral values with a leading {@code 0} will be interpreted as octal; the returned number will
    304     * be Integer, Long or BigDecimal as appropriate.
    305     * </p>
    306     *
    307     * <p>Returns {@code null} if the string is {@code null}.</p>
    308     *
    309     * <p>This method does not trim the input string, i.e., strings with leading
    310     * or trailing spaces will generate NumberFormatExceptions.</p>
    311     *
    312     * @param str  String containing a number, may be null
    313     * @return Number created from the string (or null if the input is null)
    314     * @throws NumberFormatException if the value cannot be converted
    315     */
    316    public static Number createNumber(final String str) {
    317        if (str == null) {
    318            return null;
    319        }
    320        if (StringUtils.isBlank(str)) {
    321            throw new NumberFormatException("A blank string is not a valid number");
    322        }
    323        // Need to deal with all possible hex prefixes here
    324        final String[] hexPrefixes = {"0x", "0X", "#"};
    325        final int length = str.length();
    326        final int offset = str.charAt(0) == '+' || str.charAt(0) == '-' ? 1 : 0;
    327        int pfxLen = 0;
    328        for (final String pfx : hexPrefixes) {
    329            if (str.startsWith(pfx, offset)) {
    330                pfxLen += pfx.length() + offset;
    331                break;
    332            }
    333        }
    334        if (pfxLen > 0) { // we have a hex number
    335            char firstSigDigit = 0; // strip leading zeroes
    336            for (int i = pfxLen; i < length; i++) {
    337                firstSigDigit = str.charAt(i);
    338                if (firstSigDigit != '0') {
    339                    break;
    340                }
    341                pfxLen++;
    342            }
    343            final int hexDigits = length - pfxLen;
    344            if (hexDigits > 16 || hexDigits == 16 && firstSigDigit > '7') { // too many for Long
    345                return createBigInteger(str);
    346            }
    347            if (hexDigits > 8 || hexDigits == 8 && firstSigDigit > '7') { // too many for an int
    348                return createLong(str);
    349            }
    350            return createInteger(str);
    351        }
    352        final char lastChar = str.charAt(length - 1);
    353        final String mant;
    354        final String dec;
    355        final String exp;
    356        final int decPos = str.indexOf('.');
    357        final int expPos = str.indexOf('e') + str.indexOf('E') + 1; // assumes both not present
    358        // if both e and E are present, this is caught by the checks on expPos (which prevent IOOBE)
    359        // and the parsing which will detect if e or E appear in a number due to using the wrong offset
    360
    361        // Detect if the return type has been requested
    362        final boolean requestType = !Character.isDigit(lastChar) && lastChar != '.';
    363        if (decPos > -1) { // there is a decimal point
    364            if (expPos > -1) { // there is an exponent
    365                if (expPos < decPos || expPos > length) { // prevents double exponent causing IOOBE
    366                    throw new NumberFormatException(str + " is not a valid number.");
    367                }
    368                dec = str.substring(decPos + 1, expPos);
    369            } else {
    370                // No exponent, but there may be a type character to remove
    371                dec = str.substring(decPos + 1, requestType ? length - 1 : length);
    372            }
    373            mant = getMantissa(str, decPos);
    374        } else {
    375            if (expPos > -1) {
    376                if (expPos > length) { // prevents double exponent causing IOOBE
    377                    throw new NumberFormatException(str + " is not a valid number.");
    378                }
    379                mant = getMantissa(str, expPos);
    380            } else {
    381                // No decimal, no exponent, but there may be a type character to remove
    382                mant = getMantissa(str, requestType ? length - 1 : length);
    383            }
    384            dec = null;
    385        }
    386        if (requestType) {
    387            if (expPos > -1 && expPos < length - 1) {
    388                exp = str.substring(expPos + 1, length - 1);
    389            } else {
    390                exp = null;
    391            }
    392            //Requesting a specific type.
    393            final String numeric = str.substring(0, length - 1);
    394            switch (lastChar) {
    395                case 'l' :
    396                case 'L' :
    397                    if (dec == null
    398                        && exp == null
    399                        && (!numeric.isEmpty() && numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) {
    400                        try {
    401                            return createLong(numeric);
    402                        } catch (final NumberFormatException ignored) {
    403                            // Too big for a long
    404                        }
    405                        return createBigInteger(numeric);
    406
    407                    }
    408                    throw new NumberFormatException(str + " is not a valid number.");
    409                case 'f' :
    410                case 'F' :
    411                    try {
    412                        final Float f = createFloat(str);
    413                        if (!(f.isInfinite() || f.floatValue() == 0.0F && !isZero(mant, dec))) {
    414                            //If it's too big for a float or the float value = 0 and the string
    415                            //has non-zeros in it, then float does not have the precision we want
    416                            return f;
    417                        }
    418
    419                    } catch (final NumberFormatException ignored) {
    420                        // ignore the bad number
    421                    }
    422                    //$FALL-THROUGH$
    423                case 'd' :
    424                case 'D' :
    425                    try {
    426                        final Double d = createDouble(str);
    427                        if (!(d.isInfinite() || d.doubleValue() == 0.0D && !isZero(mant, dec))) {
    428                            return d;
    429                        }
    430                    } catch (final NumberFormatException ignored) {
    431                        // ignore the bad number
    432                    }
    433                    try {
    434                        return createBigDecimal(numeric);
    435                    } catch (final NumberFormatException ignored) {
    436                        // ignore the bad number
    437                    }
    438                    //$FALL-THROUGH$
    439                default :
    440                    throw new NumberFormatException(str + " is not a valid number.");
    441
    442            }
    443        }
    444        //User doesn't have a preference on the return type, so let's start
    445        //small and go from there...
    446        if (expPos > -1 && expPos < length - 1) {
    447            exp = str.substring(expPos + 1);
    448        } else {
    449            exp = null;
    450        }
    451        if (dec == null && exp == null) { // no decimal point and no exponent
    452            //Must be an Integer, Long, Biginteger
    453            try {
    454                return createInteger(str);
    455            } catch (final NumberFormatException ignored) {
    456                // ignore the bad number
    457            }
    458            try {
    459                return createLong(str);
    460            } catch (final NumberFormatException ignored) {
    461                // ignore the bad number
    462            }
    463            return createBigInteger(str);
    464        }
    465
    466        //Must be a Float, Double, BigDecimal
    467        try {
    468            final Float f = createFloat(str);
    469            final Double d = createDouble(str);
    470            if (!f.isInfinite()
    471                    && !(f.floatValue() == 0.0F && !isZero(mant, dec))
    472                    && f.toString().equals(d.toString())) {
    473                return f;
    474            }
    475            if (!d.isInfinite() && !(d.doubleValue() == 0.0D && !isZero(mant, dec))) {
    476                final BigDecimal b = createBigDecimal(str);
    477                if (b.compareTo(BigDecimal.valueOf(d.doubleValue())) == 0) {
    478                    return d;
    479                }
    480                return b;
    481            }
    482        } catch (final NumberFormatException ignored) {
    483            // ignore the bad number
    484        }
    485        return createBigDecimal(str);
    486    }
    487
    488     /**
    489     * Utility method for {@link #createNumber(java.lang.String)}.
    490     *
    491     * <p>Returns mantissa of the given number.</p>
    492     *
    493     * @param str the string representation of the number
    494     * @param stopPos the position of the exponent or decimal point
    495     * @return mantissa of the given number
    496     */
    497    private static String getMantissa(final String str, final int stopPos) {
    498        final char firstChar = str.charAt(0);
    499        final boolean hasSign = firstChar == '-' || firstChar == '+';
    500
    501        return hasSign ? str.substring(1, stopPos) : str.substring(0, stopPos);
    502    }
    503
    504    /**
    505     * Utility method for {@link #createNumber(java.lang.String)}.
    506     *
    507     * <p>Returns {@code true} if s is {@code null} or empty.</p>
    508     *
    509     * @param str the String to check
    510     * @return if it is all zeros or {@code null}
    511     */
    512    private static boolean isAllZeros(final String str) {
    513        if (str == null) {
    514            return true;
    515        }
    516        for (int i = str.length() - 1; i >= 0; i--) {
    517            if (str.charAt(i) != '0') {
    518                return false;
    519            }
    520        }
    521        return true;
    522    }
    523
    524    /**
    525     * Checks whether the String is a valid Java number.
    526     *
    527     * <p>Valid numbers include hexadecimal marked with the {@code 0x} or
    528     * {@code 0X} qualifier, octal numbers, scientific notation and
    529     * numbers marked with a type qualifier (e.g. 123L).</p>
    530     *
    531     * <p>Non-hexadecimal strings beginning with a leading zero are
    532     * treated as octal values. Thus the string {@code 09} will return
    533     * {@code false}, since {@code 9} is not a valid octal value.
    534     * However, numbers beginning with {@code 0.} are treated as decimal.</p>
    535     *
    536     * <p>{@code null} and empty/blank {@link String} will return
    537     * {@code false}.</p>
    538     *
    539     * <p>Note, {@link #createNumber(String)} should return a number for every
    540     * input resulting in {@code true}.</p>
    541     *
    542     * @param str  the {@link String} to check
    543     * @return {@code true} if the string is a correctly formatted number
    544     * @since 3.5
    545     */
    546    public static boolean isCreatable(final String str) {
    547        if (StringUtils.isEmpty(str)) {
    548            return false;
    549        }
    550        final char[] chars = str.toCharArray();
    551        int sz = chars.length;
    552        boolean hasExp = false;
    553        boolean hasDecPoint = false;
    554        boolean allowSigns = false;
    555        boolean foundDigit = false;
    556        // deal with any possible sign up front
    557        final int start = chars[0] == '-' || chars[0] == '+' ? 1 : 0;
    558        if (sz > start + 1 && chars[start] == '0' && !StringUtils.contains(str, '.')) { // leading 0, skip if is a decimal number
    559            if (chars[start + 1] == 'x' || chars[start + 1] == 'X') { // leading 0x/0X
    560                int i = start + 2;
    561                if (i == sz) {
    562                    return false; // str == "0x"
    563                }
    564                // checking hex (it can't be anything else)
    565                for (; i < chars.length; i++) {
    566                    if ((chars[i] < '0' || chars[i] > '9')
    567                        && (chars[i] < 'a' || chars[i] > 'f')
    568                        && (chars[i] < 'A' || chars[i] > 'F')) {
    569                        return false;
    570                    }
    571                }
    572                return true;
    573           }
    574            if (Character.isDigit(chars[start + 1])) {
    575                   // leading 0, but not hex, must be octal
    576                   int i = start + 1;
    577                   for (; i < chars.length; i++) {
    578                       if (chars[i] < '0' || chars[i] > '7') {
    579                           return false;
    580                       }
    581                   }
    582                   return true;
    583               }
    584        }
    585        sz--; // don't want to loop to the last char, check it afterwards
    586              // for type qualifiers
    587        int i = start;
    588        // loop to the next to last char or to the last char if we need another digit to
    589        // make a valid number (e.g. chars[0..5] = "1234E")
    590        while (i < sz || i < sz + 1 && allowSigns && !foundDigit) {
    591            if (chars[i] >= '0' && chars[i] <= '9') {
    592                foundDigit = true;
    593                allowSigns = false;
    594
    595            } else if (chars[i] == '.') {
    596                if (hasDecPoint || hasExp) {
    597                    // two decimal points or dec in exponent
    598                    return false;
    599                }
    600                hasDecPoint = true;
    601            } else if (chars[i] == 'e' || chars[i] == 'E') {
    602                // we've already taken care of hex.
    603                if (hasExp) {
    604                    // two E's
    605                    return false;
    606                }
    607                if (!foundDigit) {
    608                    return false;
    609                }
    610                hasExp = true;
    611                allowSigns = true;
    612            } else if (chars[i] == '+' || chars[i] == '-') {
    613                if (!allowSigns) {
    614                    return false;
    615                }
    616                allowSigns = false;
    617                foundDigit = false; // we need a digit after the E
    618            } else {
    619                return false;
    620            }
    621            i++;
    622        }
    623        if (i < chars.length) {
    624            if (chars[i] >= '0' && chars[i] <= '9') {
    625                // no type qualifier, OK
    626                return true;
    627            }
    628            if (chars[i] == 'e' || chars[i] == 'E') {
    629                // can't have an E at the last byte
    630                return false;
    631            }
    632            if (chars[i] == '.') {
    633                if (hasDecPoint || hasExp) {
    634                    // two decimal points or dec in exponent
    635                    return false;
    636                }
    637                // single trailing decimal point after non-exponent is ok
    638                return foundDigit;
    639            }
    640            if (!allowSigns
    641                && (chars[i] == 'd'
    642                    || chars[i] == 'D'
    643                    || chars[i] == 'f'
    644                    || chars[i] == 'F')) {
    645                return foundDigit;
    646            }
    647            if (chars[i] == 'l'
    648                || chars[i] == 'L') {
    649                // not allowing L with an exponent or decimal point
    650                return foundDigit && !hasExp && !hasDecPoint;
    651            }
    652            // last character is illegal
    653            return false;
    654        }
    655        // allowSigns is true iff the val ends in 'E'
    656        // found digit it to make sure weird stuff like '.' and '1E-' doesn't pass
    657        return !allowSigns && foundDigit;
    658    }
    659
    660    /**
    661     * Checks whether the {@link String} contains only
    662     * digit characters.
    663     *
    664     * <p>{@code null} and empty String will return
    665     * {@code false}.</p>
    666     *
    667     * @param str  the {@link String} to check
    668     * @return {@code true} if str contains only Unicode numeric
    669     */
    670    public static boolean isDigits(final String str) {
    671        return StringUtils.isNumeric(str);
    672    }
    673
    674    /**
    675     * Checks whether the String is a valid Java number.
    676     *
    677     * <p>Valid numbers include hexadecimal marked with the {@code 0x} or
    678     * {@code 0X} qualifier, octal numbers, scientific notation and
    679     * numbers marked with a type qualifier (e.g. 123L).</p>
    680     *
    681     * <p>Non-hexadecimal strings beginning with a leading zero are
    682     * treated as octal values. Thus the string {@code 09} will return
    683     * {@code false}, since {@code 9} is not a valid octal value.
    684     * However, numbers beginning with {@code 0.} are treated as decimal.</p>
    685     *
    686     * <p>{@code null} and empty/blank {@link String} will return
    687     * {@code false}.</p>
    688     *
    689     * <p>Note, {@link #createNumber(String)} should return a number for every
    690     * input resulting in {@code true}.</p>
    691     *
    692     * @param str  the {@link String} to check
    693     * @return {@code true} if the string is a correctly formatted number
    694     * @since 3.3 the code supports hexadecimal {@code 0Xhhh} an
    695     *        octal {@code 0ddd} validation
    696     * @deprecated This feature will be removed in Lang 4,
    697     *             use {@link NumberUtils#isCreatable(String)} instead
    698     */
    699    @Deprecated
    700    public static boolean isNumber(final String str) {
    701        return isCreatable(str);
    702    }
    703
    704    /**
    705     * Checks whether the given String is a parsable number.
    706     *
    707     * <p>Parsable numbers include those Strings understood by {@link Integer#parseInt(String)},
    708     * {@link Long#parseLong(String)}, {@link Float#parseFloat(String)} or
    709     * {@link Double#parseDouble(String)}. This method can be used instead of catching {@link java.text.ParseException}
    710     * when calling one of those methods.</p>
    711     *
    712     * <p>Hexadecimal and scientific notations are <strong>not</strong> considered parsable.
    713     * See {@link #isCreatable(String)} on those cases.</p>
    714     *
    715     * <p>{@code null} and empty String will return {@code false}.</p>
    716     *
    717     * @param str the String to check.
    718     * @return {@code true} if the string is a parsable number.
    719     * @since 3.4
    720     */
    721    public static boolean isParsable(final String str) {
    722        if (StringUtils.isEmpty(str)) {
    723            return false;
    724        }
    725        if (str.charAt(str.length() - 1) == '.') {
    726            return false;
    727        }
    728        if (str.charAt(0) == '-') {
    729            if (str.length() == 1) {
    730                return false;
    731            }
    732            return withDecimalsParsing(str, 1);
    733        }
    734        return withDecimalsParsing(str, 0);
    735    }
    736
    737    /**
    738     * Utility method for {@link #createNumber(java.lang.String)}.
    739     *
    740     * <p>This will check if the magnitude of the number is zero by checking if there
    741     * are only zeros before and after the decimal place.</p>
    742     *
    743     * <p>Note: It is <strong>assumed</strong> that the input string has been converted
    744     * to either a Float or Double with a value of zero when this method is called.
    745     * This eliminates invalid input for example {@code ".", ".D", ".e0"}.</p>
    746     *
    747     * <p>Thus the method only requires checking if both arguments are null, empty or
    748     * contain only zeros.</p>
    749     *
    750     * <p>Given {@code s = mant + "." + dec}:</p>
    751     * <ul>
    752     * <li>{@code true} if s is {@code "0.0"}
    753     * <li>{@code true} if s is {@code "0."}
    754     * <li>{@code true} if s is {@code ".0"}
    755     * <li>{@code false} otherwise (this assumes {@code "."} is not possible)
    756     * </ul>
    757     *
    758     * @param mant the mantissa decimal digits before the decimal point (sign must be removed; never null)
    759     * @param dec the decimal digits after the decimal point (exponent and type specifier removed;
    760     *            can be null)
    761     * @return true if the magnitude is zero
    762     */
    763    private static boolean isZero(final String mant, final String dec) {
    764        return isAllZeros(mant) && isAllZeros(dec);
    765    }
    766
    767    /**
    768     * Returns the maximum value in an array.
    769     *
    770     * @param array  an array, must not be null or empty
    771     * @return the maximum value in the array
    772     * @throws NullPointerException if {@code array} is {@code null}
    773     * @throws IllegalArgumentException if {@code array} is empty
    774     * @since 3.4 Changed signature from max(byte[]) to max(byte...)
    775     */
    776    public static byte max(final byte... array) {
    777        // Validates input
    778        validateArray(array);
    779
    780        // Finds and returns max
    781        byte max = array[0];
    782        for (int i = 1; i < array.length; i++) {
    783            if (array[i] > max) {
    784                max = array[i];
    785            }
    786        }
    787
    788        return max;
    789    }
    790
    791    /**
    792     * Gets the maximum of three {@code byte} values.
    793     *
    794     * @param a  value 1
    795     * @param b  value 2
    796     * @param c  value 3
    797     * @return  the largest of the values
    798     */
    799    public static byte max(byte a, final byte b, final byte c) {
    800        if (b > a) {
    801            a = b;
    802        }
    803        if (c > a) {
    804            a = c;
    805        }
    806        return a;
    807    }
    808
    809    /**
    810     * Returns the maximum value in an array.
    811     *
    812     * @param array  an array, must not be null or empty
    813     * @return the maximum value in the array
    814     * @throws NullPointerException if {@code array} is {@code null}
    815     * @throws IllegalArgumentException if {@code array} is empty
    816     * @see IEEE754rUtils#max(double[]) IEEE754rUtils for a version of this method that handles NaN differently
    817     * @since 3.4 Changed signature from max(double[]) to max(double...)
    818     */
    819    public static double max(final double... array) {
    820        // Validates input
    821        validateArray(array);
    822
    823        // Finds and returns max
    824        double max = array[0];
    825        for (int j = 1; j < array.length; j++) {
    826            if (Double.isNaN(array[j])) {
    827                return Double.NaN;
    828            }
    829            if (array[j] > max) {
    830                max = array[j];
    831            }
    832        }
    833
    834        return max;
    835    }
    836
    837    /**
    838     * Gets the maximum of three {@code double} values.
    839     *
    840     * <p>If any value is {@code NaN}, {@code NaN} is
    841     * returned. Infinity is handled.</p>
    842     *
    843     * @param a  value 1
    844     * @param b  value 2
    845     * @param c  value 3
    846     * @return  the largest of the values
    847     * @see IEEE754rUtils#max(double, double, double) for a version of this method that handles NaN differently
    848     */
    849    public static double max(final double a, final double b, final double c) {
    850        return Math.max(Math.max(a, b), c);
    851    }
    852
    853    /**
    854     * Returns the maximum value in an array.
    855     *
    856     * @param array  an array, must not be null or empty
    857     * @return the maximum value in the array
    858     * @throws NullPointerException if {@code array} is {@code null}
    859     * @throws IllegalArgumentException if {@code array} is empty
    860     * @see IEEE754rUtils#max(float[]) IEEE754rUtils for a version of this method that handles NaN differently
    861     * @since 3.4 Changed signature from max(float[]) to max(float...)
    862     */
    863    public static float max(final float... array) {
    864        // Validates input
    865        validateArray(array);
    866
    867        // Finds and returns max
    868        float max = array[0];
    869        for (int j = 1; j < array.length; j++) {
    870            if (Float.isNaN(array[j])) {
    871                return Float.NaN;
    872            }
    873            if (array[j] > max) {
    874                max = array[j];
    875            }
    876        }
    877
    878        return max;
    879    }
    880
    881    // must handle Long, Float, Integer, Float, Short,
    882    //                  BigDecimal, BigInteger and Byte
    883    // useful methods:
    884    // Byte.decode(String)
    885    // Byte.valueOf(String, int radix)
    886    // Byte.valueOf(String)
    887    // Double.valueOf(String)
    888    // Float.valueOf(String)
    889    // Float.valueOf(String)
    890    // Integer.valueOf(String, int radix)
    891    // Integer.valueOf(String)
    892    // Integer.decode(String)
    893    // Integer.getInteger(String)
    894    // Integer.getInteger(String, int val)
    895    // Integer.getInteger(String, Integer val)
    896    // Integer.valueOf(String)
    897    // Double.valueOf(String)
    898    // new Byte(String)
    899    // Long.valueOf(String)
    900    // Long.getLong(String)
    901    // Long.getLong(String, int)
    902    // Long.getLong(String, Integer)
    903    // Long.valueOf(String, int)
    904    // Long.valueOf(String)
    905    // Short.valueOf(String)
    906    // Short.decode(String)
    907    // Short.valueOf(String, int)
    908    // Short.valueOf(String)
    909    // new BigDecimal(String)
    910    // new BigInteger(String)
    911    // new BigInteger(String, int radix)
    912    // Possible inputs:
    913    // 45 45.5 45E7 4.5E7 Hex Oct Binary xxxF xxxD xxxf xxxd
    914    // plus minus everything. Prolly more. A lot are not separable.
    915
    916    /**
    917     * Gets the maximum of three {@code float} values.
    918     *
    919     * <p>If any value is {@code NaN}, {@code NaN} is
    920     * returned. Infinity is handled.</p>
    921     *
    922     * @param a  value 1
    923     * @param b  value 2
    924     * @param c  value 3
    925     * @return  the largest of the values
    926     * @see IEEE754rUtils#max(float, float, float) for a version of this method that handles NaN differently
    927     */
    928    public static float max(final float a, final float b, final float c) {
    929        return Math.max(Math.max(a, b), c);
    930    }
    931
    932    /**
    933     * Returns the maximum value in an array.
    934     *
    935     * @param array  an array, must not be null or empty
    936     * @return the maximum value in the array
    937     * @throws NullPointerException if {@code array} is {@code null}
    938     * @throws IllegalArgumentException if {@code array} is empty
    939     * @since 3.4 Changed signature from max(int[]) to max(int...)
    940     */
    941    public static int max(final int... array) {
    942        // Validates input
    943        validateArray(array);
    944
    945        // Finds and returns max
    946        int max = array[0];
    947        for (int j = 1; j < array.length; j++) {
    948            if (array[j] > max) {
    949                max = array[j];
    950            }
    951        }
    952
    953        return max;
    954    }
    955
    956    /**
    957     * Gets the maximum of three {@code int} values.
    958     *
    959     * @param a  value 1
    960     * @param b  value 2
    961     * @param c  value 3
    962     * @return  the largest of the values
    963     */
    964    public static int max(int a, final int b, final int c) {
    965        if (b > a) {
    966            a = b;
    967        }
    968        if (c > a) {
    969            a = c;
    970        }
    971        return a;
    972    }
    973
    974    /**
    975     * Returns the maximum value in an array.
    976     *
    977     * @param array  an array, must not be null or empty
    978     * @return the maximum value in the array
    979     * @throws NullPointerException if {@code array} is {@code null}
    980     * @throws IllegalArgumentException if {@code array} is empty
    981     * @since 3.4 Changed signature from max(long[]) to max(long...)
    982     */
    983    public static long max(final long... array) {
    984        // Validates input
    985        validateArray(array);
    986
    987        // Finds and returns max
    988        long max = array[0];
    989        for (int j = 1; j < array.length; j++) {
    990            if (array[j] > max) {
    991                max = array[j];
    992            }
    993        }
    994
    995        return max;
    996    }
    997
    998    // 3 param max
    999    /**
    1000     * Gets the maximum of three {@code long} values.
    1001     *
    1002     * @param a  value 1
    1003     * @param b  value 2
    1004     * @param c  value 3
    1005     * @return  the largest of the values
    1006     */
    1007    public static long max(long a, final long b, final long c) {
    1008        if (b > a) {
    1009            a = b;
    1010        }
    1011        if (c > a) {
    1012            a = c;
    1013        }
    1014        return a;
    1015    }
    1016
    1017    /**
    1018     * Returns the maximum value in an array.
    1019     *
    1020     * @param array  an array, must not be null or empty
    1021     * @return the maximum value in the array
    1022     * @throws NullPointerException if {@code array} is {@code null}
    1023     * @throws IllegalArgumentException if {@code array} is empty
    1024     * @since 3.4 Changed signature from max(short[]) to max(short...)
    1025     */
    1026    public static short max(final short... array) {
    1027        // Validates input
    1028        validateArray(array);
    1029
    1030        // Finds and returns max
    1031        short max = array[0];
    1032        for (int i = 1; i < array.length; i++) {
    1033            if (array[i] > max) {
    1034                max = array[i];
    1035            }
    1036        }
    1037
    1038        return max;
    1039    }
    1040
    1041    /**
    1042     * Gets the maximum of three {@code short} values.
    1043     *
    1044     * @param a  value 1
    1045     * @param b  value 2
    1046     * @param c  value 3
    1047     * @return  the largest of the values
    1048     */
    1049    public static short max(short a, final short b, final short c) {
    1050        if (b > a) {
    1051            a = b;
    1052        }
    1053        if (c > a) {
    1054            a = c;
    1055        }
    1056        return a;
    1057    }
    1058
    1059    /**
    1060     * Returns the minimum value in an array.
    1061     *
    1062     * @param array  an array, must not be null or empty
    1063     * @return the minimum value in the array
    1064     * @throws NullPointerException if {@code array} is {@code null}
    1065     * @throws IllegalArgumentException if {@code array} is empty
    1066     * @since 3.4 Changed signature from min(byte[]) to min(byte...)
    1067     */
    1068    public static byte min(final byte... array) {
    1069        // Validates input
    1070        validateArray(array);
    1071
    1072        // Finds and returns min
    1073        byte min = array[0];
    1074        for (int i = 1; i < array.length; i++) {
    1075            if (array[i] < min) {
    1076                min = array[i];
    1077            }
    1078        }
    1079
    1080        return min;
    1081    }
    1082
    1083    /**
    1084     * Gets the minimum of three {@code byte} values.
    1085     *
    1086     * @param a  value 1
    1087     * @param b  value 2
    1088     * @param c  value 3
    1089     * @return  the smallest of the values
    1090     */
    1091    public static byte min(byte a, final byte b, final byte c) {
    1092        if (b < a) {
    1093            a = b;
    1094        }
    1095        if (c < a) {
    1096            a = c;
    1097        }
    1098        return a;
    1099    }
    1100
    1101    /**
    1102     * Returns the minimum value in an array.
    1103     *
    1104     * @param array  an array, must not be null or empty
    1105     * @return the minimum value in the array
    1106     * @throws NullPointerException if {@code array} is {@code null}
    1107     * @throws IllegalArgumentException if {@code array} is empty
    1108     * @see IEEE754rUtils#min(double[]) IEEE754rUtils for a version of this method that handles NaN differently
    1109     * @since 3.4 Changed signature from min(double[]) to min(double...)
    1110     */
    1111    public static double min(final double... array) {
    1112        // Validates input
    1113        validateArray(array);
    1114
    1115        // Finds and returns min
    1116        double min = array[0];
    1117        for (int i = 1; i < array.length; i++) {
    1118            if (Double.isNaN(array[i])) {
    1119                return Double.NaN;
    1120            }
    1121            if (array[i] < min) {
    1122                min = array[i];
    1123            }
    1124        }
    1125
    1126        return min;
    1127    }
    1128
    1129    /**
    1130     * Gets the minimum of three {@code double} values.
    1131     *
    1132     * <p>If any value is {@code NaN}, {@code NaN} is
    1133     * returned. Infinity is handled.</p>
    1134     *
    1135     * @param a  value 1
    1136     * @param b  value 2
    1137     * @param c  value 3
    1138     * @return  the smallest of the values
    1139     * @see IEEE754rUtils#min(double, double, double) for a version of this method that handles NaN differently
    1140     */
    1141    public static double min(final double a, final double b, final double c) {
    1142        return Math.min(Math.min(a, b), c);
    1143    }
    1144
    1145    /**
    1146     * Returns the minimum value in an array.
    1147     *
    1148     * @param array  an array, must not be null or empty
    1149     * @return the minimum value in the array
    1150     * @throws NullPointerException if {@code array} is {@code null}
    1151     * @throws IllegalArgumentException if {@code array} is empty
    1152     * @see IEEE754rUtils#min(float[]) IEEE754rUtils for a version of this method that handles NaN differently
    1153     * @since 3.4 Changed signature from min(float[]) to min(float...)
    1154     */
    1155    public static float min(final float... array) {
    1156        // Validates input
    1157        validateArray(array);
    1158
    1159        // Finds and returns min
    1160        float min = array[0];
    1161        for (int i = 1; i < array.length; i++) {
    1162            if (Float.isNaN(array[i])) {
    1163                return Float.NaN;
    1164            }
    1165            if (array[i] < min) {
    1166                min = array[i];
    1167            }
    1168        }
    1169
    1170        return min;
    1171    }
    1172
    1173    /**
    1174     * Gets the minimum of three {@code float} values.
    1175     *
    1176     * <p>If any value is {@code NaN}, {@code NaN} is
    1177     * returned. Infinity is handled.</p>
    1178     *
    1179     * @param a  value 1
    1180     * @param b  value 2
    1181     * @param c  value 3
    1182     * @return  the smallest of the values
    1183     * @see IEEE754rUtils#min(float, float, float) for a version of this method that handles NaN differently
    1184     */
    1185    public static float min(final float a, final float b, final float c) {
    1186        return Math.min(Math.min(a, b), c);
    1187    }
    1188
    1189    /**
    1190     * Returns the minimum value in an array.
    1191     *
    1192     * @param array  an array, must not be null or empty
    1193     * @return the minimum value in the array
    1194     * @throws NullPointerException if {@code array} is {@code null}
    1195     * @throws IllegalArgumentException if {@code array} is empty
    1196     * @since 3.4 Changed signature from min(int[]) to min(int...)
    1197     */
    1198    public static int min(final int... array) {
    1199        // Validates input
    1200        validateArray(array);
    1201
    1202        // Finds and returns min
    1203        int min = array[0];
    1204        for (int j = 1; j < array.length; j++) {
    1205            if (array[j] < min) {
    1206                min = array[j];
    1207            }
    1208        }
    1209
    1210        return min;
    1211    }
    1212
    1213     /**
    1214     * Gets the minimum of three {@code int} values.
    1215     *
    1216     * @param a  value 1
    1217     * @param b  value 2
    1218     * @param c  value 3
    1219     * @return  the smallest of the values
    1220     */
    1221    public static int min(int a, final int b, final int c) {
    1222        if (b < a) {
    1223            a = b;
    1224        }
    1225        if (c < a) {
    1226            a = c;
    1227        }
    1228        return a;
    1229    }
    1230
    1231    /**
    1232     * Returns the minimum value in an array.
    1233     *
    1234     * @param array  an array, must not be null or empty
    1235     * @return the minimum value in the array
    1236     * @throws NullPointerException if {@code array} is {@code null}
    1237     * @throws IllegalArgumentException if {@code array} is empty
    1238     * @since 3.4 Changed signature from min(long[]) to min(long...)
    1239     */
    1240    public static long min(final long... array) {
    1241        // Validates input
    1242        validateArray(array);
    1243
    1244        // Finds and returns min
    1245        long min = array[0];
    1246        for (int i = 1; i < array.length; i++) {
    1247            if (array[i] < min) {
    1248                min = array[i];
    1249            }
    1250        }
    1251
    1252        return min;
    1253    }
    1254
    1255    // 3 param min
    1256    /**
    1257     * Gets the minimum of three {@code long} values.
    1258     *
    1259     * @param a  value 1
    1260     * @param b  value 2
    1261     * @param c  value 3
    1262     * @return  the smallest of the values
    1263     */
    1264    public static long min(long a, final long b, final long c) {
    1265        if (b < a) {
    1266            a = b;
    1267        }
    1268        if (c < a) {
    1269            a = c;
    1270        }
    1271        return a;
    1272    }
    1273
    1274    /**
    1275     * Returns the minimum value in an array.
    1276     *
    1277     * @param array  an array, must not be null or empty
    1278     * @return the minimum value in the array
    1279     * @throws NullPointerException if {@code array} is {@code null}
    1280     * @throws IllegalArgumentException if {@code array} is empty
    1281     * @since 3.4 Changed signature from min(short[]) to min(short...)
    1282     */
    1283    public static short min(final short... array) {
    1284        // Validates input
    1285        validateArray(array);
    1286
    1287        // Finds and returns min
    1288        short min = array[0];
    1289        for (int i = 1; i < array.length; i++) {
    1290            if (array[i] < min) {
    1291                min = array[i];
    1292            }
    1293        }
    1294
    1295        return min;
    1296    }
    1297
    1298    /**
    1299     * Gets the minimum of three {@code short} values.
    1300     *
    1301     * @param a  value 1
    1302     * @param b  value 2
    1303     * @param c  value 3
    1304     * @return  the smallest of the values
    1305     */
    1306    public static short min(short a, final short b, final short c) {
    1307        if (b < a) {
    1308            a = b;
    1309        }
    1310        if (c < a) {
    1311            a = c;
    1312        }
    1313        return a;
    1314    }
    1315
    1316    /**
    1317     * Convert a {@link String} to a {@code byte}, returning
    1318     * {@code zero} if the conversion fails.
    1319     *
    1320     * <p>If the string is {@code null}, {@code zero} is returned.</p>
    1321     *
    1322     * <pre>
    1323     *   NumberUtils.toByte(null) = 0
    1324     *   NumberUtils.toByte("")   = 0
    1325     *   NumberUtils.toByte("1")  = 1
    1326     * </pre>
    1327     *
    1328     * @param str  the string to convert, may be null
    1329     * @return the byte represented by the string, or {@code zero} if
    1330     *  conversion fails
    1331     * @since 2.5
    1332     */
    1333    public static byte toByte(final String str) {
    1334        return toByte(str, (byte) 0);
    1335    }
    1336
    1337    /**
    1338     * Convert a {@link String} to a {@code byte}, returning a
    1339     * default value if the conversion fails.
    1340     *
    1341     * <p>If the string is {@code null}, the default value is returned.</p>
    1342     *
    1343     * <pre>
    1344     *   NumberUtils.toByte(null, 1) = 1
    1345     *   NumberUtils.toByte("", 1)   = 1
    1346     *   NumberUtils.toByte("1", 0)  = 1
    1347     * </pre>
    1348     *
    1349     * @param str  the string to convert, may be null
    1350     * @param defaultValue  the default value
    1351     * @return the byte represented by the string, or the default if conversion fails
    1352     * @since 2.5
    1353     */
    1354    public static byte toByte(final String str, final byte defaultValue) {
    1355        if (str == null) {
    1356            return defaultValue;
    1357        }
    1358        try {
    1359            return Byte.parseByte(str);
    1360        } catch (final NumberFormatException nfe) {
    1361            return defaultValue;
    1362        }
    1363    }
    1364
    1365    /**
    1366     * Convert a {@link BigDecimal} to a {@code double}.
    1367     *
    1368     * <p>If the {@link BigDecimal} {@code value} is
    1369     * {@code null}, then the specified default value is returned.</p>
    1370     *
    1371     * <pre>
    1372     *   NumberUtils.toDouble(null)                     = 0.0d
    1373     *   NumberUtils.toDouble(BigDecimal.valueOf(8.5d)) = 8.5d
    1374     * </pre>
    1375     *
    1376     * @param value the {@link BigDecimal} to convert, may be {@code null}.
    1377     * @return the double represented by the {@link BigDecimal} or
    1378     *  {@code 0.0d} if the {@link BigDecimal} is {@code null}.
    1379     * @since 3.8
    1380     */
    1381    public static double toDouble(final BigDecimal value) {
    1382        return toDouble(value, 0.0d);
    1383    }
    1384
    1385    /**
    1386     * Convert a {@link BigDecimal} to a {@code double}.
    1387     *
    1388     * <p>If the {@link BigDecimal} {@code value} is
    1389     * {@code null}, then the specified default value is returned.</p>
    1390     *
    1391     * <pre>
    1392     *   NumberUtils.toDouble(null, 1.1d)                     = 1.1d
    1393     *   NumberUtils.toDouble(BigDecimal.valueOf(8.5d), 1.1d) = 8.5d
    1394     * </pre>
    1395     *
    1396     * @param value the {@link BigDecimal} to convert, may be {@code null}.
    1397     * @param defaultValue the default value
    1398     * @return the double represented by the {@link BigDecimal} or the
    1399     *  defaultValue if the {@link BigDecimal} is {@code null}.
    1400     * @since 3.8
    1401     */
    1402    public static double toDouble(final BigDecimal value, final double defaultValue) {
    1403        return value == null ? defaultValue : value.doubleValue();
    1404    }
    1405
    1406    /**
    1407     * Convert a {@link String} to a {@code double}, returning
    1408     * {@code 0.0d} if the conversion fails.
    1409     *
    1410     * <p>If the string {@code str} is {@code null},
    1411     * {@code 0.0d} is returned.</p>
    1412     *
    1413     * <pre>
    1414     *   NumberUtils.toDouble(null)   = 0.0d
    1415     *   NumberUtils.toDouble("")     = 0.0d
    1416     *   NumberUtils.toDouble("1.5")  = 1.5d
    1417     * </pre>
    1418     *
    1419     * @param str the string to convert, may be {@code null}
    1420     * @return the double represented by the string, or {@code 0.0d}
    1421     *  if conversion fails
    1422     * @since 2.1
    1423     */
    1424    public static double toDouble(final String str) {
    1425        return toDouble(str, 0.0d);
    1426    }
    1427
    1428    /**
    1429     * Convert a {@link String} to a {@code double}, returning a
    1430     * default value if the conversion fails.
    1431     *
    1432     * <p>If the string {@code str} is {@code null}, the default
    1433     * value is returned.</p>
    1434     *
    1435     * <pre>
    1436     *   NumberUtils.toDouble(null, 1.1d)   = 1.1d
    1437     *   NumberUtils.toDouble("", 1.1d)     = 1.1d
    1438     *   NumberUtils.toDouble("1.5", 0.0d)  = 1.5d
    1439     * </pre>
    1440     *
    1441     * @param str the string to convert, may be {@code null}
    1442     * @param defaultValue the default value
    1443     * @return the double represented by the string, or defaultValue
    1444     *  if conversion fails
    1445     * @since 2.1
    1446     */
    1447    public static double toDouble(final String str, final double defaultValue) {
    1448      if (str == null) {
    1449          return defaultValue;
    1450      }
    1451      try {
    1452          return Double.parseDouble(str);
    1453      } catch (final NumberFormatException nfe) {
    1454          return defaultValue;
    1455      }
    1456    }
    1457
    1458    /**
    1459     * Convert a {@link String} to a {@code float}, returning
    1460     * {@code 0.0f} if the conversion fails.
    1461     *
    1462     * <p>If the string {@code str} is {@code null},
    1463     * {@code 0.0f} is returned.</p>
    1464     *
    1465     * <pre>
    1466     *   NumberUtils.toFloat(null)   = 0.0f
    1467     *   NumberUtils.toFloat("")     = 0.0f
    1468     *   NumberUtils.toFloat("1.5")  = 1.5f
    1469     * </pre>
    1470     *
    1471     * @param str the string to convert, may be {@code null}
    1472     * @return the float represented by the string, or {@code 0.0f}
    1473     *  if conversion fails
    1474     * @since 2.1
    1475     */
    1476    public static float toFloat(final String str) {
    1477        return toFloat(str, 0.0f);
    1478    }
    1479
    1480    /**
    1481     * Convert a {@link String} to a {@code float}, returning a
    1482     * default value if the conversion fails.
    1483     *
    1484     * <p>If the string {@code str} is {@code null}, the default
    1485     * value is returned.</p>
    1486     *
    1487     * <pre>
    1488     *   NumberUtils.toFloat(null, 1.1f)   = 1.0f
    1489     *   NumberUtils.toFloat("", 1.1f)     = 1.1f
    1490     *   NumberUtils.toFloat("1.5", 0.0f)  = 1.5f
    1491     * </pre>
    1492     *
    1493     * @param str the string to convert, may be {@code null}
    1494     * @param defaultValue the default value
    1495     * @return the float represented by the string, or defaultValue
    1496     *  if conversion fails
    1497     * @since 2.1
    1498     */
    1499    public static float toFloat(final String str, final float defaultValue) {
    1500      if (str == null) {
    1501          return defaultValue;
    1502      }
    1503      try {
    1504          return Float.parseFloat(str);
    1505      } catch (final NumberFormatException nfe) {
    1506          return defaultValue;
    1507      }
    1508    }
    1509
    1510    /**
    1511     * Convert a {@link String} to an {@code int}, returning
    1512     * {@code zero} if the conversion fails.
    1513     *
    1514     * <p>If the string is {@code null}, {@code zero} is returned.</p>
    1515     *
    1516     * <pre>
    1517     *   NumberUtils.toInt(null) = 0
    1518     *   NumberUtils.toInt("")   = 0
    1519     *   NumberUtils.toInt("1")  = 1
    1520     * </pre>
    1521     *
    1522     * @param str  the string to convert, may be null
    1523     * @return the int represented by the string, or {@code zero} if
    1524     *  conversion fails
    1525     * @since 2.1
    1526     */
    1527    public static int toInt(final String str) {
    1528        return toInt(str, 0);
    1529    }
    1530
    1531    /**
    1532     * Convert a {@link String} to an {@code int}, returning a
    1533     * default value if the conversion fails.
    1534     *
    1535     * <p>If the string is {@code null}, the default value is returned.</p>
    1536     *
    1537     * <pre>
    1538     *   NumberUtils.toInt(null, 1) = 1
    1539     *   NumberUtils.toInt("", 1)   = 1
    1540     *   NumberUtils.toInt("1", 0)  = 1
    1541     * </pre>
    1542     *
    1543     * @param str  the string to convert, may be null
    1544     * @param defaultValue  the default value
    1545     * @return the int represented by the string, or the default if conversion fails
    1546     * @since 2.1
    1547     */
    1548    public static int toInt(final String str, final int defaultValue) {
    1549        if (str == null) {
    1550            return defaultValue;
    1551        }
    1552        try {
    1553            return Integer.parseInt(str);
    1554        } catch (final NumberFormatException nfe) {
    1555            return defaultValue;
    1556        }
    1557    }
    1558
    1559    /**
    1560     * Convert a {@link String} to a {@code long}, returning
    1561     * {@code zero} if the conversion fails.
    1562     *
    1563     * <p>If the string is {@code null}, {@code zero} is returned.</p>
    1564     *
    1565     * <pre>
    1566     *   NumberUtils.toLong(null) = 0L
    1567     *   NumberUtils.toLong("")   = 0L
    1568     *   NumberUtils.toLong("1")  = 1L
    1569     * </pre>
    1570     *
    1571     * @param str  the string to convert, may be null
    1572     * @return the long represented by the string, or {@code 0} if
    1573     *  conversion fails
    1574     * @since 2.1
    1575     */
    1576    public static long toLong(final String str) {
    1577        return toLong(str, 0L);
    1578    }
    1579
    1580    /**
    1581     * Convert a {@link String} to a {@code long}, returning a
    1582     * default value if the conversion fails.
    1583     *
    1584     * <p>If the string is {@code null}, the default value is returned.</p>
    1585     *
    1586     * <pre>
    1587     *   NumberUtils.toLong(null, 1L) = 1L
    1588     *   NumberUtils.toLong("", 1L)   = 1L
    1589     *   NumberUtils.toLong("1", 0L)  = 1L
    1590     * </pre>
    1591     *
    1592     * @param str  the string to convert, may be null
    1593     * @param defaultValue  the default value
    1594     * @return the long represented by the string, or the default if conversion fails
    1595     * @since 2.1
    1596     */
    1597    public static long toLong(final String str, final long defaultValue) {
    1598        if (str == null) {
    1599            return defaultValue;
    1600        }
    1601        try {
    1602            return Long.parseLong(str);
    1603        } catch (final NumberFormatException nfe) {
    1604            return defaultValue;
    1605        }
    1606    }
    1607
    1608    /**
    1609     * Convert a {@link BigDecimal} to a {@link BigDecimal} with a scale of
    1610     * two that has been rounded using {@code RoundingMode.HALF_EVEN}. If the supplied
    1611     * {@code value} is null, then {@code BigDecimal.ZERO} is returned.
    1612     *
    1613     * <p>Note, the scale of a {@link BigDecimal} is the number of digits to the right of the
    1614     * decimal point.</p>
    1615     *
    1616     * @param value the {@link BigDecimal} to convert, may be null.
    1617     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1618     * @since 3.8
    1619     */
    1620    public static BigDecimal toScaledBigDecimal(final BigDecimal value) {
    1621        return toScaledBigDecimal(value, INTEGER_TWO, RoundingMode.HALF_EVEN);
    1622    }
    1623
    1624    /**
    1625     * Convert a {@link BigDecimal} to a {@link BigDecimal} whose scale is the
    1626     * specified value with a {@link RoundingMode} applied. If the input {@code value}
    1627     * is {@code null}, we simply return {@code BigDecimal.ZERO}.
    1628     *
    1629     * @param value the {@link BigDecimal} to convert, may be null.
    1630     * @param scale the number of digits to the right of the decimal point.
    1631     * @param roundingMode a rounding behavior for numerical operations capable of
    1632     *  discarding precision.
    1633     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1634     * @since 3.8
    1635     */
    1636    public static BigDecimal toScaledBigDecimal(final BigDecimal value, final int scale, final RoundingMode roundingMode) {
    1637        if (value == null) {
    1638            return BigDecimal.ZERO;
    1639        }
    1640        return value.setScale(
    1641            scale,
    1642            roundingMode == null ? RoundingMode.HALF_EVEN : roundingMode
    1643        );
    1644    }
    1645
    1646    /**
    1647     * Convert a {@link Double} to a {@link BigDecimal} with a scale of
    1648     * two that has been rounded using {@code RoundingMode.HALF_EVEN}. If the supplied
    1649     * {@code value} is null, then {@code BigDecimal.ZERO} is returned.
    1650     *
    1651     * <p>Note, the scale of a {@link BigDecimal} is the number of digits to the right of the
    1652     * decimal point.</p>
    1653     *
    1654     * @param value the {@link Double} to convert, may be null.
    1655     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1656     * @since 3.8
    1657     */
    1658    public static BigDecimal toScaledBigDecimal(final Double value) {
    1659        return toScaledBigDecimal(value, INTEGER_TWO, RoundingMode.HALF_EVEN);
    1660    }
    1661
    1662    /**
    1663     * Convert a {@link Double} to a {@link BigDecimal} whose scale is the
    1664     * specified value with a {@link RoundingMode} applied. If the input {@code value}
    1665     * is {@code null}, we simply return {@code BigDecimal.ZERO}.
    1666     *
    1667     * @param value the {@link Double} to convert, may be null.
    1668     * @param scale the number of digits to the right of the decimal point.
    1669     * @param roundingMode a rounding behavior for numerical operations capable of
    1670     *  discarding precision.
    1671     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1672     * @since 3.8
    1673     */
    1674    public static BigDecimal toScaledBigDecimal(final Double value, final int scale, final RoundingMode roundingMode) {
    1675        if (value == null) {
    1676            return BigDecimal.ZERO;
    1677        }
    1678        return toScaledBigDecimal(
    1679            BigDecimal.valueOf(value),
    1680            scale,
    1681            roundingMode
    1682        );
    1683    }
    1684
    1685    /**
    1686     * Convert a {@link Float} to a {@link BigDecimal} with a scale of
    1687     * two that has been rounded using {@code RoundingMode.HALF_EVEN}. If the supplied
    1688     * {@code value} is null, then {@code BigDecimal.ZERO} is returned.
    1689     *
    1690     * <p>Note, the scale of a {@link BigDecimal} is the number of digits to the right of the
    1691     * decimal point.</p>
    1692     *
    1693     * @param value the {@link Float} to convert, may be null.
    1694     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1695     * @since 3.8
    1696     */
    1697    public static BigDecimal toScaledBigDecimal(final Float value) {
    1698        return toScaledBigDecimal(value, INTEGER_TWO, RoundingMode.HALF_EVEN);
    1699    }
    1700
    1701    /**
    1702     * Convert a {@link Float} to a {@link BigDecimal} whose scale is the
    1703     * specified value with a {@link RoundingMode} applied. If the input {@code value}
    1704     * is {@code null}, we simply return {@code BigDecimal.ZERO}.
    1705     *
    1706     * @param value the {@link Float} to convert, may be null.
    1707     * @param scale the number of digits to the right of the decimal point.
    1708     * @param roundingMode a rounding behavior for numerical operations capable of
    1709     *  discarding precision.
    1710     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1711     * @since 3.8
    1712     */
    1713    public static BigDecimal toScaledBigDecimal(final Float value, final int scale, final RoundingMode roundingMode) {
    1714        if (value == null) {
    1715            return BigDecimal.ZERO;
    1716        }
    1717        return toScaledBigDecimal(
    1718            BigDecimal.valueOf(value),
    1719            scale,
    1720            roundingMode
    1721        );
    1722    }
    1723
    1724    /**
    1725     * Convert a {@link String} to a {@link BigDecimal} with a scale of
    1726     * two that has been rounded using {@code RoundingMode.HALF_EVEN}. If the supplied
    1727     * {@code value} is null, then {@code BigDecimal.ZERO} is returned.
    1728     *
    1729     * <p>Note, the scale of a {@link BigDecimal} is the number of digits to the right of the
    1730     * decimal point.</p>
    1731     *
    1732     * @param value the {@link String} to convert, may be null.
    1733     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1734     * @since 3.8
    1735     */
    1736    public static BigDecimal toScaledBigDecimal(final String value) {
    1737        return toScaledBigDecimal(value, INTEGER_TWO, RoundingMode.HALF_EVEN);
    1738    }
    1739
    1740    /**
    1741     * Convert a {@link String} to a {@link BigDecimal} whose scale is the
    1742     * specified value with a {@link RoundingMode} applied. If the input {@code value}
    1743     * is {@code null}, we simply return {@code BigDecimal.ZERO}.
    1744     *
    1745     * @param value the {@link String} to convert, may be null.
    1746     * @param scale the number of digits to the right of the decimal point.
    1747     * @param roundingMode a rounding behavior for numerical operations capable of
    1748     *  discarding precision.
    1749     * @return the scaled, with appropriate rounding, {@link BigDecimal}.
    1750     * @since 3.8
    1751     */
    1752    public static BigDecimal toScaledBigDecimal(final String value, final int scale, final RoundingMode roundingMode) {
    1753        if (value == null) {
    1754            return BigDecimal.ZERO;
    1755        }
    1756        return toScaledBigDecimal(
    1757            createBigDecimal(value),
    1758            scale,
    1759            roundingMode
    1760        );
    1761    }
    1762
    1763    /**
    1764     * Convert a {@link String} to a {@code short}, returning
    1765     * {@code zero} if the conversion fails.
    1766     *
    1767     * <p>If the string is {@code null}, {@code zero} is returned.</p>
    1768     *
    1769     * <pre>
    1770     *   NumberUtils.toShort(null) = 0
    1771     *   NumberUtils.toShort("")   = 0
    1772     *   NumberUtils.toShort("1")  = 1
    1773     * </pre>
    1774     *
    1775     * @param str  the string to convert, may be null
    1776     * @return the short represented by the string, or {@code zero} if
    1777     *  conversion fails
    1778     * @since 2.5
    1779     */
    1780    public static short toShort(final String str) {
    1781        return toShort(str, (short) 0);
    1782    }
    1783
    1784    /**
    1785     * Convert a {@link String} to an {@code short}, returning a
    1786     * default value if the conversion fails.
    1787     *
    1788     * <p>If the string is {@code null}, the default value is returned.</p>
    1789     *
    1790     * <pre>
    1791     *   NumberUtils.toShort(null, 1) = 1
    1792     *   NumberUtils.toShort("", 1)   = 1
    1793     *   NumberUtils.toShort("1", 0)  = 1
    1794     * </pre>
    1795     *
    1796     * @param str  the string to convert, may be null
    1797     * @param defaultValue  the default value
    1798     * @return the short represented by the string, or the default if conversion fails
    1799     * @since 2.5
    1800     */
    1801    public static short toShort(final String str, final short defaultValue) {
    1802        if (str == null) {
    1803            return defaultValue;
    1804        }
    1805        try {
    1806            return Short.parseShort(str);
    1807        } catch (final NumberFormatException nfe) {
    1808            return defaultValue;
    1809        }
    1810    }
    1811
    1812    /**
    1813     * Checks if the specified array is neither null nor empty.
    1814     *
    1815     * @param array  the array to check
    1816     * @throws IllegalArgumentException if {@code array} is empty
    1817     * @throws NullPointerException if {@code array} is {@code null}
    1818     */
    1819    private static void validateArray(final Object array) {
    1820        Objects.requireNonNull(array, "array");
    1821        Validate.isTrue(Array.getLength(array) != 0, "Array cannot be empty.");
    1822    }
    1823
    1824    private static boolean withDecimalsParsing(final String str, final int beginIdx) {
    1825        int decimalPoints = 0;
    1826        for (int i = beginIdx; i < str.length(); i++) {
    1827            final boolean isDecimalPoint = str.charAt(i) == '.';
    1828            if (isDecimalPoint) {
    1829                decimalPoints++;
    1830            }
    1831            if (decimalPoints > 1) {
    1832                return false;
    1833            }
    1834            if (!isDecimalPoint && !Character.isDigit(str.charAt(i))) {
    1835                return false;
    1836            }
    1837        }
    1838        return true;
    1839    }
    1840
    1841    /**
    1842     * {@link NumberUtils} instances should NOT be constructed in standard programming.
    1843     * Instead, the class should be used as {@code NumberUtils.toInt("6");}.
    1844     *
    1845     * <p>This constructor is public to permit tools that require a JavaBean instance
    1846     * to operate.</p>
    1847     */
    1848    public NumberUtils() {
    1849    }
    1850}