Class TypeFormat


  • public final class TypeFormat
    extends Object

    This class provides utility methods to parse CharSequence into primitive types and to format primitive types into StringBuffer.

    Methods from this utility class do not create temporary objects and are typically faster than standard library methods (e.g parseDouble(java.lang.CharSequence) is up to 15x faster than Double.parseDouble).

    For class instances, formatting is typically performed using specialized java.text.Format (Locale sensitive) and/or using conventional methods (class sensitive). For example:
         public class Foo {
             public static Foo valueOf(CharSequence chars) {...} // Parses.
             public StringBuffer appendTo(StringBuffer sb) {...} // Formats.
             public String toString() {
                 return appendTo(new StringBuffer()).toString();
             }
         }
     

    This class is public domain (not copyrighted).

    Version:
    4.6, June 22, 2003
    Author:
    Jean-Marie Dautelle
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static StringBuffer format​(boolean b, StringBuffer sb)
      Formats the specified boolean and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(double d, double precision, StringBuffer sb)
      Formats the specified double and appends the resulting text to the StringBuffer argument; the number of significative digits is deduced from the specified precision.
      static StringBuffer format​(double d, int digits, StringBuffer sb)
      Formats the specified double and appends the resulting text to the StringBuffer argument; the number of significand digits is specified as integer argument.
      static StringBuffer format​(double d, StringBuffer sb)
      Formats the specified double and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(float f, float precision, StringBuffer sb)
      Formats the specified float and appends the resulting text to the StringBuffer argument; the number of significative digits is deduced from the specified precision.
      static StringBuffer format​(float f, StringBuffer sb)
      Formats the specified float and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(int i, int radix, StringBuffer sb)
      Formats the specified int in the specified radix and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(int i, StringBuffer sb)
      Formats the specified int and appends the resulting text (decimal representation) to the StringBuffer argument.
      static StringBuffer format​(long l, int radix, StringBuffer sb)
      Formats the specified long in the specified radix and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(long l, StringBuffer sb)
      Formats the specified long and appends the resulting text (decimal representation) to the StringBuffer argument.
      static StringBuffer format​(short s, int radix, StringBuffer sb)
      Formats the specified short in the specified radix and appends the resulting text to the StringBuffer argument.
      static StringBuffer format​(short s, StringBuffer sb)
      Formats the specified short and appends the resulting text (decimal representation) to the StringBuffer argument.
      static int indexOf​(CharSequence pattern, CharSequence chars, int fromIndex)
      Searches for a particular sequence within a character sequence (general purpose parsing function).
      static boolean parseBoolean​(CharSequence chars)
      Parses the specified CharSequence as a boolean.
      static double parseDouble​(CharSequence chars)
      Parses this CharSequence as a double.
      static float parseFloat​(CharSequence chars)
      Parses this CharSequence as a float.
      static int parseInt​(CharSequence chars)
      Parses the specified CharSequence as a signed decimal int.
      static int parseInt​(CharSequence chars, int radix)
      Parses the specified CharSequence as a signed int in the specified radix.
      static long parseLong​(CharSequence chars)
      Parses the specified CharSequence as a signed decimal long.
      static long parseLong​(CharSequence chars, int radix)
      Parses the specified CharSequence as a signed long in the specified radix.
      static short parseShort​(CharSequence chars)
      Parses the specified CharSequence as a signed decimal short.
      static short parseShort​(CharSequence chars, int radix)
      Parses the specified CharSequence as a signed short in the specified radix.
    • Method Detail

      • indexOf

        public static int indexOf​(CharSequence pattern,
                                  CharSequence chars,
                                  int fromIndex)
        Searches for a particular sequence within a character sequence (general purpose parsing function).
        Parameters:
        pattern - the character sequence to search for.
        chars - the character sequence being searched.
        fromIndex - the index in chars to start the search from.
        Returns:
        the index in the range [fromIndex, chars.length()-pattern.length()] or -1 if the character sequence is not found.
      • parseBoolean

        public static boolean parseBoolean​(CharSequence chars)
        Parses the specified CharSequence as a boolean.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        the corresponding boolean.
      • parseShort

        public static short parseShort​(CharSequence chars)
        Parses the specified CharSequence as a signed decimal short.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        parseShort(chars, 10)
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable short.
        See Also:
        parseShort(CharSequence, int)
      • parseShort

        public static short parseShort​(CharSequence chars,
                                       int radix)
        Parses the specified CharSequence as a signed short in the specified radix. The characters in the string must all be digits of the specified radix, except the first character which may be a plus sign '+' or a minus sign '-'.
        Parameters:
        chars - the character sequence to parse.
        radix - the radix to be used while parsing.
        Returns:
        the corresponding short.
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable short.
      • parseInt

        public static int parseInt​(CharSequence chars)
        Parses the specified CharSequence as a signed decimal int.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        parseInt(chars, 10)
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable int.
        See Also:
        parseInt(CharSequence, int)
      • parseInt

        public static int parseInt​(CharSequence chars,
                                   int radix)
        Parses the specified CharSequence as a signed int in the specified radix. The characters in the string must all be digits of the specified radix, except the first character which may be a plus sign '+' or a minus sign '-'.
        Parameters:
        chars - the character sequence to parse.
        radix - the radix to be used while parsing.
        Returns:
        the corresponding int.
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable int.
      • parseLong

        public static long parseLong​(CharSequence chars)
        Parses the specified CharSequence as a signed decimal long.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        parseLong(chars, 10)
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable long.
        See Also:
        parseLong(CharSequence, int)
      • parseLong

        public static long parseLong​(CharSequence chars,
                                     int radix)
        Parses the specified CharSequence as a signed long in the specified radix. The characters in the string must all be digits of the specified radix, except the first character which may be a plus sign '+' or a minus sign '-'.
        Parameters:
        chars - the character sequence to parse.
        radix - the radix to be used while parsing.
        Returns:
        the corresponding long.
        Throws:
        NumberFormatException - if the specified character sequence does not contain a parsable long.
      • parseFloat

        public static float parseFloat​(CharSequence chars)
        Parses this CharSequence as a float.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        the float number represented by the specified character sequence.
        Throws:
        NumberFormatException - if the character sequence does not contain a parsable float.
      • parseDouble

        public static double parseDouble​(CharSequence chars)
                                  throws NumberFormatException
        Parses this CharSequence as a double.
        Parameters:
        chars - the character sequence to parse.
        Returns:
        the double number represented by this character sequence.
        Throws:
        NumberFormatException - if the character sequence does not contain a parsable double.
      • format

        public static StringBuffer format​(boolean b,
                                          StringBuffer sb)
        Formats the specified boolean and appends the resulting text to the StringBuffer argument.
        Parameters:
        b - a boolean.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        See Also:
        parseBoolean(java.lang.CharSequence)
      • format

        public static StringBuffer format​(short s,
                                          StringBuffer sb)
        Formats the specified short and appends the resulting text (decimal representation) to the StringBuffer argument.

        Note: This method is preferred to StringBuffer.append(short) as it does not create temporary String objects (several times faster for small numbers).

        Parameters:
        s - the short number.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        See Also:
        parseShort(java.lang.CharSequence)
      • format

        public static StringBuffer format​(int i,
                                          StringBuffer sb)
        Formats the specified int and appends the resulting text (decimal representation) to the StringBuffer argument.

        Note: This method is preferred to StringBuffer.append(int) as it does not create temporary String objects (several times faster for small numbers).

        Parameters:
        i - the int number.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        See Also:
        parseInt(java.lang.CharSequence)
      • format

        public static StringBuffer format​(long l,
                                          StringBuffer sb)
        Formats the specified long and appends the resulting text (decimal representation) to the StringBuffer argument.

        Note: This method is preferred to StringBuffer.append(long) as it does not create temporary String objects (several times faster for small numbers).

        Parameters:
        l - the long number.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        See Also:
        parseLong(java.lang.CharSequence)
      • format

        public static StringBuffer format​(float f,
                                          StringBuffer sb)
        Formats the specified float and appends the resulting text to the StringBuffer argument.
        Parameters:
        f - the float number.
        sb - the StringBuffer to append.
        Returns:
        format(f, 0.0f, sb)
        See Also:
        format(float, float, StringBuffer)
      • format

        public static StringBuffer format​(float f,
                                          float precision,
                                          StringBuffer sb)
        Formats the specified float and appends the resulting text to the StringBuffer argument; the number of significative digits is deduced from the specified precision. All digits at least as significant as the specified precision are represented. For example:
        • format(5.6f, 0.01f, sb) appends "5.60"
        • format(5.6f, 0.1f, sb) appends "5.6"
        • format(5.6f, 1f, sb) appends "6"
        If the precision is 0.0f, the precision is assumed to be the intrinsic float precision (64 bits IEEE 754 format); no formatting is performed, all significant digits are displayed and trailing zeros are removed.
        Parameters:
        f - the float number.
        precision - the maximum weight of the last digit represented.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        Throws:
        IllegalArgumentException - if the specified precision is negative or would result in too many digits (19+).
      • format

        public static StringBuffer format​(double d,
                                          StringBuffer sb)
        Formats the specified double and appends the resulting text to the StringBuffer argument.

        Note : This method is preferred to StringBuffer.append(double) or even String.valueOf(double) as it does not create temporary String or FloatingDecimal objects (several times faster, e.g. 15x faster for Double.MAX_VALUE).

        Parameters:
        d - the double number.
        sb - the StringBuffer to append.
        Returns:
        format(d, 0.0, sb)
        See Also:
        format(double, double, StringBuffer)
      • format

        public static StringBuffer format​(double d,
                                          int digits,
                                          StringBuffer sb)
        Formats the specified double and appends the resulting text to the StringBuffer argument; the number of significand digits is specified as integer argument.
        Parameters:
        d - the double number.
        digits - the number of significand digits (excludes exponent).
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        Throws:
        IllegalArgumentException - if the number of digits is not in range [1..19].
      • format

        public static StringBuffer format​(double d,
                                          double precision,
                                          StringBuffer sb)
        Formats the specified double and appends the resulting text to the StringBuffer argument; the number of significative digits is deduced from the specified precision. All digits at least as significant as the specified precision are represented. For example:
        • format(5.6, 0.01, sb) appends "5.60"
        • format(5.6, 0.1, sb) appends "5.6"
        • format(5.6, 1, sb) appends "6"
        If the precision is 0.0, the precision is assumed to be the intrinsic double precision (64 bits IEEE 754 format); no formatting is performed, all significant digits are displayed and trailing zeros are removed.
        Parameters:
        d - the double number.
        precision - the maximum weight of the last digit represented.
        sb - the StringBuffer to append.
        Returns:
        the specified StringBuffer object.
        Throws:
        IllegalArgumentException - if the specified precision is negative or would result in too many digits (19+).