- /* ====================================================================
- * The Apache Software License, Version 1.1
- *
- * Copyright (c) 2002-2003 The Apache Software Foundation. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. The end-user documentation included with the redistribution, if
- * any, must include the following acknowledgement:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowledgement may appear in the software itself,
- * if and wherever such third-party acknowledgements normally appear.
- *
- * 4. The names "The Jakarta Project", "Commons", and "Apache Software
- * Foundation" must not be used to endorse or promote products derived
- * from this software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache"
- * nor may "Apache" appear in their names without prior written
- * permission of the Apache Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- */
- package org.apache.commons.lang.math;
-
- import java.math.BigDecimal;
- import java.math.BigInteger;
-
- import org.apache.commons.lang.StringUtils;
-
- /**
- * <p>Provides extra functionality for Java Number classes.</p>
- *
- * @author <a href="mailto:bayard@generationjava.com">Henri Yandell</a>
- * @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a>
- * @author Stephen Colebourne
- * @author <a href="mailto:steve.downey@netfolio.com">Steve Downey</a>
- * @author Eric Pugh
- * @author Phil Steitz
- * @author Matthew Hawthorne
- * @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a>
- * @since 2.0
- * @version $Id: NumberUtils.java,v 1.10 2003/08/18 02:22:24 bayard Exp $
- */
- public class NumberUtils {
-
- /** Reusable Long constant for zero. */
- public static final Long LONG_ZERO = new Long(0L);
- /** Reusable Long constant for one. */
- public static final Long LONG_ONE = new Long(1L);
- /** Reusable Long constant for minus one. */
- public static final Long LONG_MINUS_ONE = new Long(-1L);
- /** Reusable Integer constant for zero. */
- public static final Integer INTEGER_ZERO = new Integer(0);
- /** Reusable Integer constant for one. */
- public static final Integer INTEGER_ONE = new Integer(1);
- /** Reusable Integer constant for minus one. */
- public static final Integer INTEGER_MINUS_ONE = new Integer(-1);
- /** Reusable Short constant for zero. */
- public static final Short SHORT_ZERO = new Short((short) 0);
- /** Reusable Short constant for one. */
- public static final Short SHORT_ONE = new Short((short) 1);
- /** Reusable Short constant for minus one. */
- public static final Short SHORT_MINUS_ONE = new Short((short) -1);
- /** Reusable Byte constant for zero. */
- public static final Byte BYTE_ZERO = new Byte((byte) 0);
- /** Reusable Byte constant for one. */
- public static final Byte BYTE_ONE = new Byte((byte) 1);
- /** Reusable Byte constant for minus one. */
- public static final Byte BYTE_MINUS_ONE = new Byte((byte) -1);
- /** Reusable Double constant for zero. */
- public static final Double DOUBLE_ZERO = new Double(0.0d);
- /** Reusable Double constant for one. */
- public static final Double DOUBLE_ONE = new Double(1.0d);
- /** Reusable Double constant for minus one. */
- public static final Double DOUBLE_MINUS_ONE = new Double(-1.0d);
- /** Reusable Float constant for zero. */
- public static final Float FLOAT_ZERO = new Float(0.0f);
- /** Reusable Float constant for one. */
- public static final Float FLOAT_ONE = new Float(1.0f);
- /** Reusable Float constant for minus one. */
- public static final Float FLOAT_MINUS_ONE = new Float(-1.0f);
-
- /**
- * <p><code>NumberUtils</code> instances should NOT be constructed in standard programming.
- * Instead, the class should be used as <code>NumberUtils.stringToInt("6");</code>.</p>
- *
- * <p>This constructor is public to permit tools that require a JavaBean instance
- * to operate.</p>
- */
- public NumberUtils() {
- }
-
- //-----------------------------------------------------------------------
- /**
- * <p>Convert a <code>String</code> to an <code>int</code>, returning
- * <code>zero</code> if the conversion fails.</p>
- *
- * <p>If the string is <code>null</code>, <code>zero</code> is returned.</p>
- *
- * @param str the string to convert, may be null
- * @return the int represented by the string, or <code>zero</code> if
- * conversion fails
- */
- public static int stringToInt(String str) {
- return stringToInt(str, 0);
- }
-
- /**
- * <p>Convert a <code>String</code> to an <code>int</code>, returning a
- * default value if the conversion fails.</p>
- *
- * <p>If the string is <code>null</code>, the default value is returned.</p>
- *
- * @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
- */
- public static int stringToInt(String str, int defaultValue) {
- try {
- return Integer.parseInt(str);
- } catch (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)
- // new Float(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)
- // new Integer(String)
- // new Double(String)
- // new Byte(String)
- // new Long(String)
- // Long.getLong(String)
- // Long.getLong(String,int)
- // Long.getLong(String,Integer)
- // Long.valueOf(String,int)
- // Long.valueOf(String)
- // new Short(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.
-
- /**
- * <p>Turns a string value into a java.lang.Number.</p>
- *
- * <p>First, the value is examined for a type qualifier on the end
- * (<code>'f','F','d','D','l','L'</code>). 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.</p>
- *
- * <p>If a type specifier is not found, it will check for a decimal point
- * and then try successively larger types from <code>Integer</code> to
- * <code>BigInteger</code> and from <code>Float</code> to
- * <code>BigDecimal</code>.</p>
- *
- * <p>If the string starts with <code>0x</code> or <code>-0x</code>, it
- * will be interpreted as a hexadecimal integer. Values with leading
- * <code>0</code>'s will not be interpreted as octal.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * <p>This method does not trim the input string, i.e., strings with leading
- * or trailing spaces will generate NumberFormatExceptions.</p>
- *
- * @param str String containing a number, may be null
- * @return Number created from the string
- * @throws NumberFormatException if the value cannot be converted
- */
- public static Number createNumber(String str) throws NumberFormatException {
- if (str == null) {
- return null;
- }
- if (StringUtils.isBlank(str)) {
- throw new NumberFormatException("A blank string is not a valid number");
- }
- if (str.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.
- return null;
- }
- if (str.startsWith("0x") || str.startsWith("-0x")) {
- return createInteger(str);
- }
- char lastChar = str.charAt(str.length() - 1);
- String mant;
- String dec;
- String exp;
- int decPos = str.indexOf('.');
- int expPos = str.indexOf('e') + str.indexOf('E') + 1;
-
- if (decPos > -1) {
-
- if (expPos > -1) {
- if (expPos < decPos) {
- throw new NumberFormatException(str + " is not a valid number.");
- }
- dec = str.substring(decPos + 1, expPos);
- } else {
- dec = str.substring(decPos + 1);
- }
- mant = str.substring(0, decPos);
- } else {
- if (expPos > -1) {
- mant = str.substring(0, expPos);
- } else {
- mant = str;
- }
- dec = null;
- }
- if (!Character.isDigit(lastChar)) {
- if (expPos > -1 && expPos < str.length() - 1) {
- exp = str.substring(expPos + 1, str.length() - 1);
- } else {
- exp = null;
- }
- //Requesting a specific type..
- String numeric = str.substring(0, str.length() - 1);
- boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
- switch (lastChar) {
- case 'l' :
- case 'L' :
- if (dec == null
- && exp == null
- && isDigits(numeric.substring(1))
- && (numeric.charAt(0) == '-' || Character.isDigit(numeric.charAt(0)))) {
- try {
- return createLong(numeric);
- } catch (NumberFormatException nfe) {
- //Too big for a long
- }
- return createBigInteger(numeric);
-
- }
- throw new NumberFormatException(str + " is not a valid number.");
- case 'f' :
- case 'F' :
- try {
- 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 doens't have the presision we want
- return f;
- }
-
- } catch (NumberFormatException nfe) {
- }
- //Fall through
- case 'd' :
- case 'D' :
- try {
- Double d = NumberUtils.createDouble(numeric);
- if (!(d.isInfinite() || (d.floatValue() == 0.0D && !allZeros))) {
- return d;
- }
- } catch (NumberFormatException nfe) {
- }
- try {
- return createBigDecimal(numeric);
- } catch (NumberFormatException e) {
- }
- //Fall through
- default :
- throw new NumberFormatException(str + " is not a valid number.");
-
- }
- } else {
- //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) {
- //Must be an int,long,bigint
- try {
- return createInteger(str);
- } catch (NumberFormatException nfe) {
- }
- try {
- return createLong(str);
- } catch (NumberFormatException nfe) {
- }
- return createBigInteger(str);
-
- } else {
- //Must be a float,double,BigDec
- boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
- try {
- Float f = createFloat(str);
- if (!(f.isInfinite() || (f.floatValue() == 0.0F && !allZeros))) {
- return f;
- }
- } catch (NumberFormatException nfe) {
- }
- try {
- Double d = createDouble(str);
- if (!(d.isInfinite() || (d.doubleValue() == 0.0D && !allZeros))) {
- return d;
- }
- } catch (NumberFormatException nfe) {
- }
-
- return createBigDecimal(str);
-
- }
- }
- }
-
- /**
- * <p>Utility method for {@link #createNumber(java.lang.String)}.</p>
- *
- * <p>Returns <code>true</code> if s is <code>null</code>.</p>
- *
- * @param str the String to check
- * @return if it is all zeros or <code>null</code>
- */
- private static boolean isAllZeros(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;
- }
-
- //-----------------------------------------------------------------------
- /**
- * <p>Convert a <code>String</code> to a <code>Float</code>.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>Float</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static Float createFloat(String str) {
- if (str == null) {
- return null;
- }
- return Float.valueOf(str);
- }
-
- /**
- * <p>Convert a <code>String</code> to a <code>Double</code>.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>Double</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static Double createDouble(String str) {
- if (str == null) {
- return null;
- }
- return Double.valueOf(str);
- }
-
- /**
- * <p>Convert a <code>String</code> to a <code>Integer</code>, handling
- * hex and octal notations.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>Integer</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static Integer createInteger(String str) {
- if (str == null) {
- return null;
- }
- // decode() handles 0xAABD and 0777 (hex and octal) as well.
- return Integer.decode(str);
- }
-
- /**
- * <p>Convert a <code>String</code> to a <code>Long</code>.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>Long</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static Long createLong(String str) {
- if (str == null) {
- return null;
- }
- return Long.valueOf(str);
- }
-
- /**
- * <p>Convert a <code>String</code> to a <code>BigInteger</code>.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>BigInteger</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static BigInteger createBigInteger(String str) {
- if (str == null) {
- return null;
- }
- return new BigInteger(str);
- }
-
- /**
- * <p>Convert a <code>String</code> to a <code>BigDecimal</code>.</p>
- *
- * <p>Returns <code>null</code> if the string is <code>null</code>.</p>
- *
- * @param str a <code>String</code> to convert, may be null
- * @return converted <code>BigDecimal</code>
- * @throws NumberFormatException if the value cannot be converted
- */
- public static BigDecimal createBigDecimal(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");
- }
- return new BigDecimal(str);
- }
-
- // Min in array
- //--------------------------------------------------------------------
- /**
- * <p>Returns the minimum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static long min(long[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the minimum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static int min(int[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the minimum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static short min(short[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the minimum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static double min(double[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // Finds and returns min
- double min = array[0];
- for (int i = 1; i < array.length; i++) {
- if (array[i] < min) {
- min = array[i];
- }
- }
-
- return min;
- }
-
- /**
- * <p>Returns the minimum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static float min(float[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // Finds and returns min
- float min = array[0];
- for (int i = 1; i < array.length; i++) {
- if (array[i] < min) {
- min = array[i];
- }
- }
-
- return min;
- }
-
- // Max in array
- //--------------------------------------------------------------------
- /**
- * <p>Returns the maximum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static long max(long[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the maximum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static int max(int[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the maximum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static short max(short[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // 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;
- }
-
- /**
- * <p>Returns the maximum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static double max(double[] array) {
- // Validates input
- if (array== null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // Finds and returns max
- double max = array[0];
- for (int j = 1; j < array.length; j++) {
- if (array[j] > max) {
- max = array[j];
- }
- }
-
- return max;
- }
-
- /**
- * <p>Returns the maximum value in an array.</p>
- *
- * @param array an array, must not be null or empty
- * @return the minimum value in the array
- * @throws IllegalArgumentException if <code>array</code> is <code>null</code>
- * @throws IllegalArgumentException if <code>array</code> is empty
- */
- public static float max(float[] array) {
- // Validates input
- if (array == null) {
- throw new IllegalArgumentException("The Array must not be null");
- } else if (array.length == 0) {
- throw new IllegalArgumentException("Array cannot be empty.");
- }
-
- // Finds and returns max
- float max = array[0];
- for (int j = 1; j < array.length; j++) {
- if (array[j] > max) {
- max = array[j];
- }
- }
-
- return max;
- }
-
- // 3 param min
- //-----------------------------------------------------------------------
- /**
- * <p>Gets the minimum of three <code>long</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static long min(long a, long b, long c) {
- if (b < a) {
- a = b;
- }
- if (c < a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the minimum of three <code>int</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static int min(int a, int b, int c) {
- if (b < a) {
- a = b;
- }
- if (c < a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the minimum of three <code>short</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static short min(short a, short b, short c) {
- if (b < a) {
- a = b;
- }
- if (c < a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the minimum of three <code>byte</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static byte min(byte a, byte b, byte c) {
- if (b < a) {
- a = b;
- }
- if (c < a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the minimum of three <code>double</code> values.</p>
- *
- * <p>If any value is <code>NaN</code>, <code>NaN</code> is
- * returned. Infinity is handled.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static double min(double a, double b, double c) {
- return Math.min(Math.min(a, b), c);
- }
-
- /**
- * <p>Gets the minimum of three <code>float</code> values.</p>
- *
- * <p>If any value is <code>NaN</code>, <code>NaN</code> is
- * returned. Infinity is handled.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the smallest of the values
- */
- public static float min(float a, float b, float c) {
- return Math.min(Math.min(a, b), c);
- }
-
- // 3 param max
- //-----------------------------------------------------------------------
- /**
- * <p>Gets the maximum of three <code>long</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static long max(long a, long b, long c) {
- if (b > a) {
- a = b;
- }
- if (c > a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the maximum of three <code>int</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static int max(int a, int b, int c) {
- if (b > a) {
- a = b;
- }
- if (c > a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the maximum of three <code>short</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static short max(short a, short b, short c) {
- if (b > a) {
- a = b;
- }
- if (c > a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the maximum of three <code>byte</code> values.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static byte max(byte a, byte b, byte c) {
- if (b > a) {
- a = b;
- }
- if (c > a) {
- a = c;
- }
- return a;
- }
-
- /**
- * <p>Gets the maximum of three <code>double</code> values.</p>
- *
- * <p>If any value is <code>NaN</code>, <code>NaN</code> is
- * returned. Infinity is handled.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static double max(double a, double b, double c) {
- return Math.max(Math.max(a, b), c);
- }
-
- /**
- * <p>Gets the maximum of three <code>float</code> values.</p>
- *
- * <p>If any value is <code>NaN</code>, <code>NaN</code> is
- * returned. Infinity is handled.</p>
- *
- * @param a value 1
- * @param b value 2
- * @param c value 3
- * @return the largest of the values
- */
- public static float max(float a, float b, float c) {
- return Math.max(Math.max(a, b), c);
- }
-
- //-----------------------------------------------------------------------
- /**
- * <p>Compares two <code>doubles</code> for order.</p>
- *
- * <p>This method is more comprehensive than the standard Java greater
- * than, less than and equals operators.</p>
- * <ul>
- * <li>It returns <code>-1</code> if the first value is less than the second.</li>
- * <li>It returns <code>+1</code> if the first value is greater than the second.</li>
- * <li>It returns <code>0</code> if the values are equal.</li>
- * </ul>
- *
- * <p>
- * The ordering is as follows, largest to smallest:
- * <ul>
- * <li>NaN
- * <li>Positive infinity
- * <li>Maximum double
- * <li>Normal positve numbers
- * <li>+0.0
- * <li>-0.0
- * <li>Normal negative numbers
- * <li>Minimum double (<code>-Double.MAX_VALUE</code>)
- * <li>Negative infinity
- * </ul>
- * </p>
- *
- * <p>Comparing <code>NaN</code> with <code>NaN</code> will
- * return <code>0</code>.</p>
- *
- * @param lhs the first <code>double</code>
- * @param rhs the second <code>double</code>
- * @return <code>-1</code> if lhs is less, <code>+1</code> if greater,
- * <code>0</code> if equal to rhs
- */
- public static int compare(double lhs, double rhs) {
- if (lhs < rhs) {
- return -1;
- }
- if (lhs > rhs) {
- return +1;
- }
- // Need to compare bits to handle 0.0 == -0.0 being true
- // compare should put -0.0 < +0.0
- // Two NaNs are also == for compare purposes
- // where NaN == NaN is false
- long lhsBits = Double.doubleToLongBits(lhs);
- long rhsBits = Double.doubleToLongBits(rhs);
- if (lhsBits == rhsBits) {
- return 0;
- }
- // Something exotic! A comparison to NaN or 0.0 vs -0.0
- // Fortunately NaN's long is > than everything else
- // Also negzeros bits < poszero
- // NAN: 9221120237041090560
- // MAX: 9218868437227405311
- // NEGZERO: -9223372036854775808
- if (lhsBits < rhsBits) {
- return -1;
- } else {
- return +1;
- }
- }
-
- /**
- * <p>Compares two floats for order.</p>
- *
- * <p>This method is more comprhensive than the standard Java greater than,
- * less than and equals operators.</p>
- * <ul>
- * <li>It returns <code>-1</code> if the first value is less than the second.
- * <li>It returns <code>+1</code> if the first value is greater than the second.
- * <li>It returns <code>0</code> if the values are equal.
- * </ul>
- *
- * <p> The ordering is as follows, largest to smallest:
- * <ul>
- * <li>NaN
- * <li>Positive infinity
- * <li>Maximum float
- * <li>Normal positve numbers
- * <li>+0.0
- * <li>-0.0
- * <li>Normal negative numbers
- * <li>Minimum float (<code>-Float.MAX_VALUE</code>)
- * <li>Negative infinity
- * </ul>
- *
- * <p>Comparing <code>NaN</code> with <code>NaN</code> will return
- * <code>0</code>.</p>
- *
- * @param lhs the first <code>float</code>
- * @param rhs the second <code>float</code>
- * @return <code>-1</code> if lhs is less, <code>+1</code> if greater,
- * <code>0</code> if equal to rhs
- */
- public static int compare(float lhs, float rhs) {
- if (lhs < rhs) {
- return -1;
- }
- if (lhs > rhs) {
- return +1;
- }
- //Need to compare bits to handle 0.0 == -0.0 being true
- // compare should put -0.0 < +0.0
- // Two NaNs are also == for compare purposes
- // where NaN == NaN is false
- int lhsBits = Float.floatToIntBits(lhs);
- int rhsBits = Float.floatToIntBits(rhs);
- if (lhsBits == rhsBits) {
- return 0;
- }
- //Something exotic! A comparison to NaN or 0.0 vs -0.0
- //Fortunately NaN's int is > than everything else
- //Also negzeros bits < poszero
- //NAN: 2143289344
- //MAX: 2139095039
- //NEGZERO: -2147483648
- if (lhsBits < rhsBits) {
- return -1;
- } else {
- return +1;
- }
- }
-
- //-----------------------------------------------------------------------
- /**
- * <p>Checks whether the <code>String</code> contains only
- * digit characters.</p>
- *
- * <p><code>Null</code> and empty String will return
- * <code>false</code>.</p>
- *
- * @param str the <code>String</code> to check
- * @return <code>true</code> if str contains only unicode numeric
- */
- public static boolean isDigits(String str) {
- if ((str == null) || (str.length() == 0)) {
- return false;
- }
- for (int i = 0; i < str.length(); i++) {
- if (!Character.isDigit(str.charAt(i))) {
- return false;
- }
- }
- return true;
- }
-
- /**
- * <p>Checks whether the String a valid Java number.</p>
- *
- * <p>Valid numbers include hexadecimal marked with the <code>0x</code>
- * qualifier, scientific notation and numbers marked with a type
- * qualifier (e.g. 123L).</p>
- *
- * <p><code>Null</code> and empty String will return
- * <code>false</code>.</p>
- *
- * @param str the <code>String</code> to check
- * @return <code>true</code> if the string is a correctly formatted number
- */
- public static boolean isNumber(String str) {
- if ((str == null) || (str.length() == 0)) {
- return false;
- }
- 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
- int start = (chars[0] == '-') ? 1 : 0;
- if (sz > start + 1) {
- if (chars[start] == '0' && chars[start + 1] == 'x') {
- 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;
- }
- }
- 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 (!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 exponoent
- return foundDigit && !hasExp;
- }
- // 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;
- }
-
- }