org.apache.commons.lang3.math.NumberUtils Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.commons.lang3.math;
import java.lang.reflect.Array;
import java.math.BigDecimal;
import java.math.BigInteger;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
/**
* Provides extra functionality for Java Number classes.
*
* @since 2.0
* @version $Id: NumberUtils.java 1663129 2015-03-01 16:48:22Z britter $
*/
public class NumberUtils {
/** Reusable Long constant for zero. */
public static final Long LONG_ZERO = Long.valueOf(0L);
/** Reusable Long constant for one. */
public static final Long LONG_ONE = Long.valueOf(1L);
/** Reusable Long constant for minus one. */
public static final Long LONG_MINUS_ONE = Long.valueOf(-1L);
/** Reusable Integer constant for zero. */
public static final Integer INTEGER_ZERO = Integer.valueOf(0);
/** Reusable Integer constant for one. */
public static final Integer INTEGER_ONE = Integer.valueOf(1);
/** Reusable Integer constant for minus one. */
public static final Integer INTEGER_MINUS_ONE = Integer.valueOf(-1);
/** Reusable Short constant for zero. */
public static final Short SHORT_ZERO = Short.valueOf((short) 0);
/** Reusable Short constant for one. */
public static final Short SHORT_ONE = Short.valueOf((short) 1);
/** Reusable Short constant for minus one. */
public static final Short SHORT_MINUS_ONE = Short.valueOf((short) -1);
/** Reusable Byte constant for zero. */
public static final Byte BYTE_ZERO = Byte.valueOf((byte) 0);
/** Reusable Byte constant for one. */
public static final Byte BYTE_ONE = Byte.valueOf((byte) 1);
/** Reusable Byte constant for minus one. */
public static final Byte BYTE_MINUS_ONE = Byte.valueOf((byte) -1);
/** Reusable Double constant for zero. */
public static final Double DOUBLE_ZERO = Double.valueOf(0.0d);
/** Reusable Double constant for one. */
public static final Double DOUBLE_ONE = Double.valueOf(1.0d);
/** Reusable Double constant for minus one. */
public static final Double DOUBLE_MINUS_ONE = Double.valueOf(-1.0d);
/** Reusable Float constant for zero. */
public static final Float FLOAT_ZERO = Float.valueOf(0.0f);
/** Reusable Float constant for one. */
public static final Float FLOAT_ONE = Float.valueOf(1.0f);
/** Reusable Float constant for minus one. */
public static final Float FLOAT_MINUS_ONE = Float.valueOf(-1.0f);
/**
* NumberUtils instances should NOT be constructed in standard programming.
* Instead, the class should be used as NumberUtils.toInt("6");.
*
* This constructor is public to permit tools that require a JavaBean instance
* to operate.
*/
public NumberUtils() {
super();
}
//-----------------------------------------------------------------------
/**
* Convert a String to an int, returning
* zero if the conversion fails.
*
* If the string is null, zero is returned.
*
*
* NumberUtils.toInt(null) = 0
* NumberUtils.toInt("") = 0
* NumberUtils.toInt("1") = 1
*
*
* @param str the string to convert, may be null
* @return the int represented by the string, or zero if
* conversion fails
* @since 2.1
*/
public static int toInt(final String str) {
return toInt(str, 0);
}
/**
* Convert a String to an int, returning a
* default value if the conversion fails.
*
* If the string is null, the default value is returned.
*
*
* NumberUtils.toInt(null, 1) = 1
* NumberUtils.toInt("", 1) = 1
* NumberUtils.toInt("1", 0) = 1
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the int represented by the string, or the default if conversion fails
* @since 2.1
*/
public static int toInt(final String str, final int defaultValue) {
if(str == null) {
return defaultValue;
}
try {
return Integer.parseInt(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
/**
* Convert a String to a long, returning
* zero if the conversion fails.
*
* If the string is null, zero is returned.
*
*
* NumberUtils.toLong(null) = 0L
* NumberUtils.toLong("") = 0L
* NumberUtils.toLong("1") = 1L
*
*
* @param str the string to convert, may be null
* @return the long represented by the string, or 0 if
* conversion fails
* @since 2.1
*/
public static long toLong(final String str) {
return toLong(str, 0L);
}
/**
* Convert a String to a long, returning a
* default value if the conversion fails.
*
* If the string is null, the default value is returned.
*
*
* NumberUtils.toLong(null, 1L) = 1L
* NumberUtils.toLong("", 1L) = 1L
* NumberUtils.toLong("1", 0L) = 1L
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the long represented by the string, or the default if conversion fails
* @since 2.1
*/
public static long toLong(final String str, final long defaultValue) {
if (str == null) {
return defaultValue;
}
try {
return Long.parseLong(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
/**
* Convert a String to a float, returning
* 0.0f if the conversion fails.
*
* If the string str is null,
* 0.0f is returned.
*
*
* NumberUtils.toFloat(null) = 0.0f
* NumberUtils.toFloat("") = 0.0f
* NumberUtils.toFloat("1.5") = 1.5f
*
*
* @param str the string to convert, may be null
* @return the float represented by the string, or 0.0f
* if conversion fails
* @since 2.1
*/
public static float toFloat(final String str) {
return toFloat(str, 0.0f);
}
/**
* Convert a String to a float, returning a
* default value if the conversion fails.
*
* If the string str is null, the default
* value is returned.
*
*
* NumberUtils.toFloat(null, 1.1f) = 1.0f
* NumberUtils.toFloat("", 1.1f) = 1.1f
* NumberUtils.toFloat("1.5", 0.0f) = 1.5f
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the float represented by the string, or defaultValue
* if conversion fails
* @since 2.1
*/
public static float toFloat(final String str, final float defaultValue) {
if (str == null) {
return defaultValue;
}
try {
return Float.parseFloat(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
/**
* Convert a String to a double, returning
* 0.0d if the conversion fails.
*
* If the string str is null,
* 0.0d is returned.
*
*
* NumberUtils.toDouble(null) = 0.0d
* NumberUtils.toDouble("") = 0.0d
* NumberUtils.toDouble("1.5") = 1.5d
*
*
* @param str the string to convert, may be null
* @return the double represented by the string, or 0.0d
* if conversion fails
* @since 2.1
*/
public static double toDouble(final String str) {
return toDouble(str, 0.0d);
}
/**
* Convert a String to a double, returning a
* default value if the conversion fails.
*
* If the string str is null, the default
* value is returned.
*
*
* NumberUtils.toDouble(null, 1.1d) = 1.1d
* NumberUtils.toDouble("", 1.1d) = 1.1d
* NumberUtils.toDouble("1.5", 0.0d) = 1.5d
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the double represented by the string, or defaultValue
* if conversion fails
* @since 2.1
*/
public static double toDouble(final String str, final double defaultValue) {
if (str == null) {
return defaultValue;
}
try {
return Double.parseDouble(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
//-----------------------------------------------------------------------
/**
* Convert a String to a byte, returning
* zero if the conversion fails.
*
* If the string is null, zero is returned.
*
*
* NumberUtils.toByte(null) = 0
* NumberUtils.toByte("") = 0
* NumberUtils.toByte("1") = 1
*
*
* @param str the string to convert, may be null
* @return the byte represented by the string, or zero if
* conversion fails
* @since 2.5
*/
public static byte toByte(final String str) {
return toByte(str, (byte) 0);
}
/**
* Convert a String to a byte, returning a
* default value if the conversion fails.
*
* If the string is null, the default value is returned.
*
*
* NumberUtils.toByte(null, 1) = 1
* NumberUtils.toByte("", 1) = 1
* NumberUtils.toByte("1", 0) = 1
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the byte represented by the string, or the default if conversion fails
* @since 2.5
*/
public static byte toByte(final String str, final byte defaultValue) {
if(str == null) {
return defaultValue;
}
try {
return Byte.parseByte(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
/**
* Convert a String to a short, returning
* zero if the conversion fails.
*
* If the string is null, zero is returned.
*
*
* NumberUtils.toShort(null) = 0
* NumberUtils.toShort("") = 0
* NumberUtils.toShort("1") = 1
*
*
* @param str the string to convert, may be null
* @return the short represented by the string, or zero if
* conversion fails
* @since 2.5
*/
public static short toShort(final String str) {
return toShort(str, (short) 0);
}
/**
* Convert a String to an short, returning a
* default value if the conversion fails.
*
* If the string is null, the default value is returned.
*
*
* NumberUtils.toShort(null, 1) = 1
* NumberUtils.toShort("", 1) = 1
* NumberUtils.toShort("1", 0) = 1
*
*
* @param str the string to convert, may be null
* @param defaultValue the default value
* @return the short represented by the string, or the default if conversion fails
* @since 2.5
*/
public static short toShort(final String str, final short defaultValue) {
if(str == null) {
return defaultValue;
}
try {
return Short.parseShort(str);
} catch (final NumberFormatException nfe) {
return defaultValue;
}
}
//-----------------------------------------------------------------------
// must handle Long, Float, Integer, Float, Short,
// BigDecimal, BigInteger and Byte
// useful methods:
// Byte.decode(String)
// Byte.valueOf(String,int radix)
// Byte.valueOf(String)
// Double.valueOf(String)
// Float.valueOf(String)
// Float.valueOf(String)
// Integer.valueOf(String,int radix)
// Integer.valueOf(String)
// Integer.decode(String)
// Integer.getInteger(String)
// Integer.getInteger(String,int val)
// Integer.getInteger(String,Integer val)
// Integer.valueOf(String)
// Double.valueOf(String)
// new Byte(String)
// Long.valueOf(String)
// Long.getLong(String)
// Long.getLong(String,int)
// Long.getLong(String,Integer)
// Long.valueOf(String,int)
// Long.valueOf(String)
// Short.valueOf(String)
// Short.decode(String)
// Short.valueOf(String,int)
// Short.valueOf(String)
// new BigDecimal(String)
// new BigInteger(String)
// new BigInteger(String,int radix)
// Possible inputs:
// 45 45.5 45E7 4.5E7 Hex Oct Binary xxxF xxxD xxxf xxxd
// plus minus everything. Prolly more. A lot are not separable.
/**
* Turns a string value into a java.lang.Number.
*
* If the string starts with {@code 0x} or {@code -0x} (lower or upper case) or {@code #} or {@code -#}, it
* will be interpreted as a hexadecimal Integer - or Long, if the number of digits after the
* prefix is more than 8 - or BigInteger if there are more than 16 digits.
*
* Then, the value is examined for a type qualifier on the end, i.e. one of
* 'f','F','d','D','l','L'. If it is found, it starts
* trying to create successively larger types from the type specified
* until one is found that can represent the value.
*
* If a type specifier is not found, it will check for a decimal point
* and then try successively larger types from Integer to
* BigInteger and from Float to
* BigDecimal.
*
*
* Integral values with a leading {@code 0} will be interpreted as octal; the returned number will
* be Integer, Long or BigDecimal as appropriate.
*
*
* Returns null if the string is null.
*
* This method does not trim the input string, i.e., strings with leading
* or trailing spaces will generate NumberFormatExceptions.
*
* @param str String containing a number, may be null
* @return Number created from the string (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static Number createNumber(final String str) throws NumberFormatException {
if (str == null) {
return null;
}
if (StringUtils.isBlank(str)) {
throw new NumberFormatException("A blank string is not a valid number");
}
// Need to deal with all possible hex prefixes here
final String[] hex_prefixes = {"0x", "0X", "-0x", "-0X", "#", "-#"};
int pfxLen = 0;
for(final String pfx : hex_prefixes) {
if (str.startsWith(pfx)) {
pfxLen += pfx.length();
break;
}
}
if (pfxLen > 0) { // we have a hex number
char firstSigDigit = 0; // strip leading zeroes
for(int i = pfxLen; i < str.length(); i++) {
firstSigDigit = str.charAt(i);
if (firstSigDigit == '0') { // count leading zeroes
pfxLen++;
} else {
break;
}
}
final int hexDigits = str.length() - pfxLen;
if (hexDigits > 16 || (hexDigits == 16 && firstSigDigit > '7')) { // too many for Long
return createBigInteger(str);
}
if (hexDigits > 8 || (hexDigits == 8 && firstSigDigit > '7')) { // too many for an int
return createLong(str);
}
return createInteger(str);
}
final char lastChar = str.charAt(str.length() - 1);
String mant;
String dec;
String exp;
final int decPos = str.indexOf('.');
final int expPos = str.indexOf('e') + str.indexOf('E') + 1; // assumes both not present
// if both e and E are present, this is caught by the checks on expPos (which prevent IOOBE)
// and the parsing which will detect if e or E appear in a number due to using the wrong offset
int numDecimals = 0; // Check required precision (LANG-693)
if (decPos > -1) { // there is a decimal point
if (expPos > -1) { // there is an exponent
if (expPos < decPos || expPos > str.length()) { // prevents double exponent causing IOOBE
throw new NumberFormatException(str + " is not a valid number.");
}
dec = str.substring(decPos + 1, expPos);
} else {
dec = str.substring(decPos + 1);
}
mant = getMantissa(str, decPos);
numDecimals = dec.length(); // gets number of digits past the decimal to ensure no loss of precision for floating point numbers.
} else {
if (expPos > -1) {
if (expPos > str.length()) { // prevents double exponent causing IOOBE
throw new NumberFormatException(str + " is not a valid number.");
}
mant = getMantissa(str, expPos);
} else {
mant = getMantissa(str);
}
dec = null;
}
if (!Character.isDigit(lastChar) && lastChar != '.') {
if (expPos > -1 && expPos < str.length() - 1) {
exp = str.substring(expPos + 1, str.length() - 1);
} else {
exp = null;
}
//Requesting a specific type..
final String numeric = str.substring(0, str.length() - 1);
final boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
switch (lastChar) {
case 'l' :
case 'L' :
if (dec == null
&& exp == null
&& (numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) {
try {
return createLong(numeric);
} catch (final NumberFormatException nfe) { // NOPMD
// Too big for a long
}
return createBigInteger(numeric);
}
throw new NumberFormatException(str + " is not a valid number.");
case 'f' :
case 'F' :
try {
final Float f = NumberUtils.createFloat(numeric);
if (!(f.isInfinite() || (f.floatValue() == 0.0F && !allZeros))) {
//If it's too big for a float or the float value = 0 and the string
//has non-zeros in it, then float does not have the precision we want
return f;
}
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
//$FALL-THROUGH$
case 'd' :
case 'D' :
try {
final Double d = NumberUtils.createDouble(numeric);
if (!(d.isInfinite() || (d.floatValue() == 0.0D && !allZeros))) {
return d;
}
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
try {
return createBigDecimal(numeric);
} catch (final NumberFormatException e) { // NOPMD
// ignore the bad number
}
//$FALL-THROUGH$
default :
throw new NumberFormatException(str + " is not a valid number.");
}
}
//User doesn't have a preference on the return type, so let's start
//small and go from there...
if (expPos > -1 && expPos < str.length() - 1) {
exp = str.substring(expPos + 1, str.length());
} else {
exp = null;
}
if (dec == null && exp == null) { // no decimal point and no exponent
//Must be an Integer, Long, Biginteger
try {
return createInteger(str);
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
try {
return createLong(str);
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
return createBigInteger(str);
}
//Must be a Float, Double, BigDecimal
final boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
try {
if(numDecimals <= 7){// If number has 7 or fewer digits past the decimal point then make it a float
final Float f = createFloat(str);
if (!(f.isInfinite() || (f.floatValue() == 0.0F && !allZeros))) {
return f;
}
}
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
try {
if(numDecimals <= 16){// If number has between 8 and 16 digits past the decimal point then make it a double
final Double d = createDouble(str);
if (!(d.isInfinite() || (d.doubleValue() == 0.0D && !allZeros))) {
return d;
}
}
} catch (final NumberFormatException nfe) { // NOPMD
// ignore the bad number
}
return createBigDecimal(str);
}
/**
* Utility method for {@link #createNumber(java.lang.String)}.
*
* Returns mantissa of the given number.
*
* @param str the string representation of the number
* @return mantissa of the given number
*/
private static String getMantissa(final String str) {
return getMantissa(str, str.length());
}
/**
* Utility method for {@link #createNumber(java.lang.String)}.
*
* Returns mantissa of the given number.
*
* @param str the string representation of the number
* @param stopPos the position of the exponent or decimal point
* @return mantissa of the given number
*/
private static String getMantissa(final String str, final int stopPos) {
final char firstChar = str.charAt(0);
final boolean hasSign = (firstChar == '-' || firstChar == '+');
return hasSign ? str.substring(1, stopPos) : str.substring(0, stopPos);
}
/**
* Utility method for {@link #createNumber(java.lang.String)}.
*
* Returns true if s is null.
*
* @param str the String to check
* @return if it is all zeros or null
*/
private static boolean isAllZeros(final String str) {
if (str == null) {
return true;
}
for (int i = str.length() - 1; i >= 0; i--) {
if (str.charAt(i) != '0') {
return false;
}
}
return str.length() > 0;
}
//-----------------------------------------------------------------------
/**
* Convert a String to a Float.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted Float (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static Float createFloat(final String str) {
if (str == null) {
return null;
}
return Float.valueOf(str);
}
/**
* Convert a String to a Double.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted Double (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static Double createDouble(final String str) {
if (str == null) {
return null;
}
return Double.valueOf(str);
}
/**
* Convert a String to a Integer, handling
* hex (0xhhhh) and octal (0dddd) notations.
* N.B. a leading zero means octal; spaces are not trimmed.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted Integer (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static Integer createInteger(final String str) {
if (str == null) {
return null;
}
// decode() handles 0xAABD and 0777 (hex and octal) as well.
return Integer.decode(str);
}
/**
* Convert a String to a Long;
* since 3.1 it handles hex (0Xhhhh) and octal (0ddd) notations.
* N.B. a leading zero means octal; spaces are not trimmed.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted Long (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static Long createLong(final String str) {
if (str == null) {
return null;
}
return Long.decode(str);
}
/**
* Convert a String to a BigInteger;
* since 3.2 it handles hex (0x or #) and octal (0) notations.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted BigInteger (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static BigInteger createBigInteger(final String str) {
if (str == null) {
return null;
}
int pos = 0; // offset within string
int radix = 10;
boolean negate = false; // need to negate later?
if (str.startsWith("-")) {
negate = true;
pos = 1;
}
if (str.startsWith("0x", pos) || str.startsWith("0X", pos)) { // hex
radix = 16;
pos += 2;
} else if (str.startsWith("#", pos)) { // alternative hex (allowed by Long/Integer)
radix = 16;
pos ++;
} else if (str.startsWith("0", pos) && str.length() > pos + 1) { // octal; so long as there are additional digits
radix = 8;
pos ++;
} // default is to treat as decimal
final BigInteger value = new BigInteger(str.substring(pos), radix);
return negate ? value.negate() : value;
}
/**
* Convert a String to a BigDecimal.
*
* Returns null if the string is null.
*
* @param str a String to convert, may be null
* @return converted BigDecimal (or null if the input is null)
* @throws NumberFormatException if the value cannot be converted
*/
public static BigDecimal createBigDecimal(final String str) {
if (str == null) {
return null;
}
// handle JDK1.3.1 bug where "" throws IndexOutOfBoundsException
if (StringUtils.isBlank(str)) {
throw new NumberFormatException("A blank string is not a valid number");
}
if (str.trim().startsWith("--")) {
// this is protection for poorness in java.lang.BigDecimal.
// it accepts this as a legal value, but it does not appear
// to be in specification of class. OS X Java parses it to
// a wrong value.
throw new NumberFormatException(str + " is not a valid number.");
}
return new BigDecimal(str);
}
// Min in array
//--------------------------------------------------------------------
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from min(long[]) to min(long...)
*/
public static long min(final long... array) {
// Validates input
validateArray(array);
// Finds and returns min
long min = array[0];
for (int i = 1; i < array.length; i++) {
if (array[i] < min) {
min = array[i];
}
}
return min;
}
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from min(int[]) to min(int...)
*/
public static int min(final int... array) {
// Validates input
validateArray(array);
// Finds and returns min
int min = array[0];
for (int j = 1; j < array.length; j++) {
if (array[j] < min) {
min = array[j];
}
}
return min;
}
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from min(short[]) to min(short...)
*/
public static short min(final short... array) {
// Validates input
validateArray(array);
// Finds and returns min
short min = array[0];
for (int i = 1; i < array.length; i++) {
if (array[i] < min) {
min = array[i];
}
}
return min;
}
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from min(byte[]) to min(byte...)
*/
public static byte min(final byte... array) {
// Validates input
validateArray(array);
// Finds and returns min
byte min = array[0];
for (int i = 1; i < array.length; i++) {
if (array[i] < min) {
min = array[i];
}
}
return min;
}
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @see IEEE754rUtils#min(double[]) IEEE754rUtils for a version of this method that handles NaN differently
* @since 3.4 Changed signature from min(double[]) to min(double...)
*/
public static double min(final double... array) {
// Validates input
validateArray(array);
// Finds and returns min
double min = array[0];
for (int i = 1; i < array.length; i++) {
if (Double.isNaN(array[i])) {
return Double.NaN;
}
if (array[i] < min) {
min = array[i];
}
}
return min;
}
/**
* Returns the minimum value in an array.
*
* @param array an array, must not be null or empty
* @return the minimum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @see IEEE754rUtils#min(float[]) IEEE754rUtils for a version of this method that handles NaN differently
* @since 3.4 Changed signature from min(float[]) to min(float...)
*/
public static float min(final float... array) {
// Validates input
validateArray(array);
// Finds and returns min
float min = array[0];
for (int i = 1; i < array.length; i++) {
if (Float.isNaN(array[i])) {
return Float.NaN;
}
if (array[i] < min) {
min = array[i];
}
}
return min;
}
// Max in array
//--------------------------------------------------------------------
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from max(long[]) to max(long...)
*/
public static long max(final long... array) {
// Validates input
validateArray(array);
// Finds and returns max
long max = array[0];
for (int j = 1; j < array.length; j++) {
if (array[j] > max) {
max = array[j];
}
}
return max;
}
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from max(int[]) to max(int...)
*/
public static int max(final int... array) {
// Validates input
validateArray(array);
// Finds and returns max
int max = array[0];
for (int j = 1; j < array.length; j++) {
if (array[j] > max) {
max = array[j];
}
}
return max;
}
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from max(short[]) to max(short...)
*/
public static short max(final short... array) {
// Validates input
validateArray(array);
// Finds and returns max
short max = array[0];
for (int i = 1; i < array.length; i++) {
if (array[i] > max) {
max = array[i];
}
}
return max;
}
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @since 3.4 Changed signature from max(byte[]) to max(byte...)
*/
public static byte max(final byte... array) {
// Validates input
validateArray(array);
// Finds and returns max
byte max = array[0];
for (int i = 1; i < array.length; i++) {
if (array[i] > max) {
max = array[i];
}
}
return max;
}
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @see IEEE754rUtils#max(double[]) IEEE754rUtils for a version of this method that handles NaN differently
* @since 3.4 Changed signature from max(double[]) to max(double...)
*/
public static double max(final double... array) {
// Validates input
validateArray(array);
// Finds and returns max
double max = array[0];
for (int j = 1; j < array.length; j++) {
if (Double.isNaN(array[j])) {
return Double.NaN;
}
if (array[j] > max) {
max = array[j];
}
}
return max;
}
/**
* Returns the maximum value in an array.
*
* @param array an array, must not be null or empty
* @return the maximum value in the array
* @throws IllegalArgumentException if array is null
* @throws IllegalArgumentException if array is empty
* @see IEEE754rUtils#max(float[]) IEEE754rUtils for a version of this method that handles NaN differently
* @since 3.4 Changed signature from max(float[]) to max(float...)
*/
public static float max(final float... array) {
// Validates input
validateArray(array);
// Finds and returns max
float max = array[0];
for (int j = 1; j < array.length; j++) {
if (Float.isNaN(array[j])) {
return Float.NaN;
}
if (array[j] > max) {
max = array[j];
}
}
return max;
}
/**
* Checks if the specified array is neither null nor empty.
*
* @param array the array to check
* @throws IllegalArgumentException if {@code array} is either {@code null} or empty
*/
private static void validateArray(final Object array) {
if (array == null) {
throw new IllegalArgumentException("The Array must not be null");
}
Validate.isTrue(Array.getLength(array) != 0, "Array cannot be empty.");
}
// 3 param min
//-----------------------------------------------------------------------
/**
* Gets the minimum of three long values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
*/
public static long min(long a, final long b, final long c) {
if (b < a) {
a = b;
}
if (c < a) {
a = c;
}
return a;
}
/**
* Gets the minimum of three int values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
*/
public static int min(int a, final int b, final int c) {
if (b < a) {
a = b;
}
if (c < a) {
a = c;
}
return a;
}
/**
* Gets the minimum of three short values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
*/
public static short min(short a, final short b, final short c) {
if (b < a) {
a = b;
}
if (c < a) {
a = c;
}
return a;
}
/**
* Gets the minimum of three byte values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
*/
public static byte min(byte a, final byte b, final byte c) {
if (b < a) {
a = b;
}
if (c < a) {
a = c;
}
return a;
}
/**
* Gets the minimum of three double values.
*
* If any value is NaN, NaN is
* returned. Infinity is handled.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
* @see IEEE754rUtils#min(double, double, double) for a version of this method that handles NaN differently
*/
public static double min(final double a, final double b, final double c) {
return Math.min(Math.min(a, b), c);
}
/**
* Gets the minimum of three float values.
*
* If any value is NaN, NaN is
* returned. Infinity is handled.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the smallest of the values
* @see IEEE754rUtils#min(float, float, float) for a version of this method that handles NaN differently
*/
public static float min(final float a, final float b, final float c) {
return Math.min(Math.min(a, b), c);
}
// 3 param max
//-----------------------------------------------------------------------
/**
* Gets the maximum of three long values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
*/
public static long max(long a, final long b, final long c) {
if (b > a) {
a = b;
}
if (c > a) {
a = c;
}
return a;
}
/**
* Gets the maximum of three int values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
*/
public static int max(int a, final int b, final int c) {
if (b > a) {
a = b;
}
if (c > a) {
a = c;
}
return a;
}
/**
* Gets the maximum of three short values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
*/
public static short max(short a, final short b, final short c) {
if (b > a) {
a = b;
}
if (c > a) {
a = c;
}
return a;
}
/**
* Gets the maximum of three byte values.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
*/
public static byte max(byte a, final byte b, final byte c) {
if (b > a) {
a = b;
}
if (c > a) {
a = c;
}
return a;
}
/**
* Gets the maximum of three double values.
*
* If any value is NaN, NaN is
* returned. Infinity is handled.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
* @see IEEE754rUtils#max(double, double, double) for a version of this method that handles NaN differently
*/
public static double max(final double a, final double b, final double c) {
return Math.max(Math.max(a, b), c);
}
/**
* Gets the maximum of three float values.
*
* If any value is NaN, NaN is
* returned. Infinity is handled.
*
* @param a value 1
* @param b value 2
* @param c value 3
* @return the largest of the values
* @see IEEE754rUtils#max(float, float, float) for a version of this method that handles NaN differently
*/
public static float max(final float a, final float b, final float c) {
return Math.max(Math.max(a, b), c);
}
//-----------------------------------------------------------------------
/**
* Checks whether the String contains only
* digit characters.
*
* Null and empty String will return
* false.
*
* @param str the String to check
* @return true if str contains only Unicode numeric
*/
public static boolean isDigits(final String str) {
if (StringUtils.isEmpty(str)) {
return false;
}
for (int i = 0; i < str.length(); i++) {
if (!Character.isDigit(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* Checks whether the String a valid Java number.
*
* Valid numbers include hexadecimal marked with the 0x or
* 0X qualifier, octal numbers, scientific notation and numbers
* marked with a type qualifier (e.g. 123L).
*
* Non-hexadecimal strings beginning with a leading zero are
* treated as octal values. Thus the string 09 will return
* false, since 9 is not a valid octal value.
* However, numbers beginning with {@code 0.} are treated as decimal.
*
* null and empty/blank {@code String} will return
* false.
*
* @param str the String to check
* @return true if the string is a correctly formatted number
* @since 3.3 the code supports hex {@code 0Xhhh} and octal {@code 0ddd} validation
*/
public static boolean isNumber(final String str) {
if (StringUtils.isEmpty(str)) {
return false;
}
final char[] chars = str.toCharArray();
int sz = chars.length;
boolean hasExp = false;
boolean hasDecPoint = false;
boolean allowSigns = false;
boolean foundDigit = false;
// deal with any possible sign up front
final int start = (chars[0] == '-') ? 1 : 0;
if (sz > start + 1 && chars[start] == '0') { // leading 0
if (
(chars[start + 1] == 'x') ||
(chars[start + 1] == 'X')
) { // leading 0x/0X
int i = start + 2;
if (i == sz) {
return false; // str == "0x"
}
// checking hex (it can't be anything else)
for (; i < chars.length; i++) {
if ((chars[i] < '0' || chars[i] > '9')
&& (chars[i] < 'a' || chars[i] > 'f')
&& (chars[i] < 'A' || chars[i] > 'F')) {
return false;
}
}
return true;
} else if (Character.isDigit(chars[start + 1])) {
// leading 0, but not hex, must be octal
int i = start + 1;
for (; i < chars.length; i++) {
if (chars[i] < '0' || chars[i] > '7') {
return false;
}
}
return true;
}
}
sz--; // don't want to loop to the last char, check it afterwords
// for type qualifiers
int i = start;
// loop to the next to last char or to the last char if we need another digit to
// make a valid number (e.g. chars[0..5] = "1234E")
while (i < sz || (i < sz + 1 && allowSigns && !foundDigit)) {
if (chars[i] >= '0' && chars[i] <= '9') {
foundDigit = true;
allowSigns = false;
} else if (chars[i] == '.') {
if (hasDecPoint || hasExp) {
// two decimal points or dec in exponent
return false;
}
hasDecPoint = true;
} else if (chars[i] == 'e' || chars[i] == 'E') {
// we've already taken care of hex.
if (hasExp) {
// two E's
return false;
}
if (!foundDigit) {
return false;
}
hasExp = true;
allowSigns = true;
} else if (chars[i] == '+' || chars[i] == '-') {
if (!allowSigns) {
return false;
}
allowSigns = false;
foundDigit = false; // we need a digit after the E
} else {
return false;
}
i++;
}
if (i < chars.length) {
if (chars[i] >= '0' && chars[i] <= '9') {
// no type qualifier, OK
return true;
}
if (chars[i] == 'e' || chars[i] == 'E') {
// can't have an E at the last byte
return false;
}
if (chars[i] == '.') {
if (hasDecPoint || hasExp) {
// two decimal points or dec in exponent
return false;
}
// single trailing decimal point after non-exponent is ok
return foundDigit;
}
if (!allowSigns
&& (chars[i] == 'd'
|| chars[i] == 'D'
|| chars[i] == 'f'
|| chars[i] == 'F')) {
return foundDigit;
}
if (chars[i] == 'l'
|| chars[i] == 'L') {
// not allowing L with an exponent or decimal point
return foundDigit && !hasExp && !hasDecPoint;
}
// last character is illegal
return false;
}
// allowSigns is true iff the val ends in 'E'
// found digit it to make sure weird stuff like '.' and '1E-' doesn't pass
return !allowSigns && foundDigit;
}
/**
* Checks whether the given String is a parsable number.
*
* Parsable numbers include those Strings understood by {@link Integer#parseInt(String)},
* {@link Long#parseLong(String)}, {@link Float#parseFloat(String)} or
* {@link Double#parseDouble(String)}. This method can be used instead of catching {@link java.text.ParseException}
* when calling one of those methods.
*
* Hexadecimal and scientific notations are not considered parsable.
* See {@link #isNumber(String)} on those cases.
*
* {@code Null} and empty String will return false.
*
* @param str the String to check.
* @return {@code true} if the string is a parsable number.
* @since 3.4
*/
public static boolean isParsable(final String str) {
if( StringUtils.endsWith( str, "." ) ) {
return false;
}
if( StringUtils.startsWith( str, "-" ) ) {
return isDigits( StringUtils.replaceOnce( str.substring(1), ".", StringUtils.EMPTY ) );
} else {
return isDigits( StringUtils.replaceOnce( str, ".", StringUtils.EMPTY ) );
}
}
/**
* Compares two {@code int} values numerically. This is the same functionality as provided in Java 7.
*
* @param x the first {@code int} to compare
* @param y the second {@code int} to compare
* @return the value {@code 0} if {@code x == y};
* a value less than {@code 0} if {@code x < y}; and
* a value greater than {@code 0} if {@code x > y}
* @since 3.4
*/
public static int compare(int x, int y) {
if (x == y) {
return 0;
}
if (x < y) {
return -1;
} else {
return 1;
}
}
/**
* Compares to {@code long} values numerically. This is the same functionality as provided in Java 7.
*
* @param x the first {@code long} to compare
* @param y the second {@code long} to compare
* @return the value {@code 0} if {@code x == y};
* a value less than {@code 0} if {@code x < y}; and
* a value greater than {@code 0} if {@code x > y}
* @since 3.4
*/
public static int compare(long x, long y) {
if (x == y) {
return 0;
}
if (x < y) {
return -1;
} else {
return 1;
}
}
/**
* Compares to {@code short} values numerically. This is the same functionality as provided in Java 7.
*
* @param x the first {@code short} to compare
* @param y the second {@code short} to compare
* @return the value {@code 0} if {@code x == y};
* a value less than {@code 0} if {@code x < y}; and
* a value greater than {@code 0} if {@code x > y}
* @since 3.4
*/
public static int compare(short x, short y) {
if (x == y) {
return 0;
}
if (x < y) {
return -1;
} else {
return 1;
}
}
/**
* Compares two {@code byte} values numerically. This is the same functionality as provided in Java 7.
*
* @param x the first {@code byte} to compare
* @param y the second {@code byte} to compare
* @return the value {@code 0} if {@code x == y};
* a value less than {@code 0} if {@code x < y}; and
* a value greater than {@code 0} if {@code x > y}
* @since 3.4
*/
public static int compare(byte x, byte y) {
return x-y;
}
}
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