Provides extra functionality for Java Number classes.
+ * + * @since 2.0 + * @version $Id$ + */ +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(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(String str, int defaultValue) {
+ if(str == null) {
+ return defaultValue;
+ }
+ try {
+ return Integer.parseInt(str);
+ } catch (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(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(String str, long defaultValue) {
+ if (str == null) {
+ return defaultValue;
+ }
+ try {
+ return Long.parseLong(str);
+ } catch (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(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(String str, float defaultValue) {
+ if (str == null) {
+ return defaultValue;
+ }
+ try {
+ return Float.parseFloat(str);
+ } catch (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(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(String str, double defaultValue) {
+ if (str == null) {
+ return defaultValue;
+ }
+ try {
+ return Double.parseDouble(str);
+ } catch (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(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(String str, byte defaultValue) {
+ if(str == null) {
+ return defaultValue;
+ }
+ try {
+ return Byte.parseByte(str);
+ } catch (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(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(String str, short defaultValue) {
+ if(str == null) {
+ return defaultValue;
+ }
+ try {
+ return Short.parseShort(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)
+ // 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.
+ * + *First, the value is examined for a type qualifier on the end
+ * ('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.
If the string starts with 0x or -0x (lower or upper case), it
+ * will be interpreted as a hexadecimal integer. Values with leading
+ * 0's will not be interpreted as octal.
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(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 || expPos > str.length()) { + 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) { + if (expPos > str.length()) { + throw new NumberFormatException(str + " is not a valid number."); + } + mant = str.substring(0, expPos); + } else { + mant = 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.. + 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 + && (numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) { + try { + return createLong(numeric); + } catch (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 { + 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 (NumberFormatException nfe) { // NOPMD + // ignore the bad number + } + //$FALL-THROUGH$ + case 'd' : + case 'D' : + try { + Double d = NumberUtils.createDouble(numeric); + if (!(d.isInfinite() || (d.floatValue() == 0.0D && !allZeros))) { + return d; + } + } catch (NumberFormatException nfe) { // NOPMD + // ignore the bad number + } + try { + return createBigDecimal(numeric); + } catch (NumberFormatException e) { // NOPMD + // ignore the bad number + } + //$FALL-THROUGH$ + 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) { // NOPMD + // ignore the bad number + } + try { + return createLong(str); + } catch (NumberFormatException nfe) { // NOPMD + // ignore the bad number + } + 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) { // NOPMD + // ignore the bad number + } + try { + Double d = createDouble(str); + if (!(d.isInfinite() || (d.doubleValue() == 0.0D && !allZeros))) { + return d; + } + } catch (NumberFormatException nfe) { // NOPMD + // ignore the bad number + } + + return createBigDecimal(str); + + } + } + } + + /** + *Utility method for {@link #createNumber(java.lang.String)}.
+ * + *Returns true if s is null.
null
+ */
+ 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;
+ }
+
+ //-----------------------------------------------------------------------
+ /**
+ * Convert a String to a Float.
Returns null if the string is null.
String to convert, may be null
+ * @return converted Float
+ * @throws NumberFormatException if the value cannot be converted
+ */
+ public static Float createFloat(String str) {
+ if (str == null) {
+ return null;
+ }
+ return Float.valueOf(str);
+ }
+
+ /**
+ * Convert a String to a Double.
Returns null if the string is null.
String to convert, may be null
+ * @return converted Double
+ * @throws NumberFormatException if the value cannot be converted
+ */
+ public static Double createDouble(String str) {
+ if (str == null) {
+ return null;
+ }
+ return Double.valueOf(str);
+ }
+
+ /**
+ * Convert a String to a Integer, handling
+ * hex and octal notations.
Returns null if the string is null.
String to convert, may be null
+ * @return converted Integer
+ * @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);
+ }
+
+ /**
+ * Convert a String to a Long.
Returns null if the string is null.
String to convert, may be null
+ * @return converted Long
+ * @throws NumberFormatException if the value cannot be converted
+ */
+ public static Long createLong(String str) {
+ if (str == null) {
+ return null;
+ }
+ return Long.valueOf(str);
+ }
+
+ /**
+ * Convert a String to a BigInteger.
Returns null if the string is null.
String to convert, may be null
+ * @return converted BigInteger
+ * @throws NumberFormatException if the value cannot be converted
+ */
+ public static BigInteger createBigInteger(String str) {
+ if (str == null) {
+ return null;
+ }
+ return new BigInteger(str);
+ }
+
+ /**
+ * Convert a String to a BigDecimal.
Returns null if the string is null.
String to convert, may be null
+ * @return converted BigDecimal
+ * @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
+ //--------------------------------------------------------------------
+ /**
+ * 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 ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * 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 ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * 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 ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * 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 ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ */
+ public static byte min(byte[] 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
+ 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 ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ * @see IEEE754rUtils#min(double[]) IEEE754rUtils for a version of this method that handles NaN differently
+ */
+ 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 (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 ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ * @see IEEE754rUtils#min(float[]) IEEE754rUtils for a version of this method that handles NaN differently
+ */
+ 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 (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 minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * Returns the maximum value in an array.
+ * + * @param array an array, must not be null or empty + * @return the minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * Returns the maximum value in an array.
+ * + * @param array an array, must not be null or empty + * @return the minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array 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;
+ }
+
+ /**
+ * Returns the maximum value in an array.
+ * + * @param array an array, must not be null or empty + * @return the minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ */
+ public static byte max(byte[] 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
+ 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 minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ * @see IEEE754rUtils#max(double[]) IEEE754rUtils for a version of this method that handles NaN differently
+ */
+ 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 (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 minimum value in the array + * @throws IllegalArgumentException ifarray is null
+ * @throws IllegalArgumentException if array is empty
+ * @see IEEE754rUtils#max(float[]) IEEE754rUtils for a version of this method that handles NaN differently
+ */
+ 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 (Float.isNaN(array[j])) {
+ return Float.NaN;
+ }
+ if (array[j] > max) {
+ max = array[j];
+ }
+ }
+
+ return max;
+ }
+
+ // 3 param min
+ //-----------------------------------------------------------------------
+ /**
+ * Gets the minimum of three long values.
Gets the minimum of three int values.
Gets the minimum of three short values.
Gets the minimum of three byte values.
Gets the minimum of three double values.
If any value is NaN, NaN is
+ * returned. Infinity is handled.
Gets the minimum of three float values.
If any value is NaN, NaN is
+ * returned. Infinity is handled.
Gets the maximum of three long values.
Gets the maximum of three int values.
Gets the maximum of three short values.
Gets the maximum of three byte values.
Gets the maximum of three double values.
If any value is NaN, NaN is
+ * returned. Infinity is handled.
Gets the maximum of three float values.
If any value is NaN, NaN is
+ * returned. Infinity is handled.
Checks whether the String contains only
+ * digit characters.
Null and empty String will return
+ * false.
String to check
+ * @return true if str contains only Unicode numeric
+ */
+ public static boolean isDigits(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
+ * qualifier, scientific notation and numbers marked with a type
+ * qualifier (e.g. 123L).
Null and empty String will return
+ * false.
String to check
+ * @return true if the string is a correctly formatted number
+ */
+ public static boolean isNumber(String str) {
+ if (StringUtils.isEmpty(str)) {
+ 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 && 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 (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;
+ }
+
+}