Field Detail

• EMPTY

  public static final CharSet EMPTY

  A CharSet defining no characters.

  Since:

  2.0

• ASCII_ALPHA

  public static final CharSet ASCII_ALPHA

  A CharSet defining ASCII alphabetic characters "a-zA-Z".

  Since:

  2.0

• ASCII_ALPHA_LOWER

  public static final CharSet ASCII_ALPHA_LOWER

  A CharSet defining ASCII alphabetic characters "a-z".

  Since:

  2.0

• ASCII_ALPHA_UPPER

  public static final CharSet ASCII_ALPHA_UPPER

  A CharSet defining ASCII alphabetic characters "A-Z".

  Since:

  2.0

• ASCII_NUMERIC

  public static final CharSet ASCII_NUMERIC

  A CharSet defining ASCII alphabetic characters "0-9".

  Since:

  2.0

• COMMON

  protected static final Map<String,CharSet> COMMON

  A Map of the common cases used in the factory. Subclasses can add more common patterns if desired

  Since:

  2.0

Constructor Detail

• CharSet

  protected CharSet(String... set)

  Constructs a new CharSet using the set syntax. Each string is merged in with the set.

  Parameters:

  set - Strings to merge into the initial set

  Throws:

  NullPointerException - if set is null

Method Detail

• getInstance

  public static CharSet getInstance(String... setStrs)

  Factory method to create a new CharSet using a special syntax.

  • null or empty string ("") - set containing no characters
  • Single character, such as "a" - set containing just that character
  • Multi character, such as "a-e" - set containing characters from one character to the other
  • Negated, such as "^a" or "^a-e" - set containing all characters except those defined
  • Combinations, such as "abe-g" - set containing all the characters from the individual sets

  The matching order is:

  1. Negated multi character range, such as "^a-e"
  2. Ordinary multi character range, such as "a-e"
  3. Negated single character, such as "^a"
  4. Ordinary single character, such as "a"

  Matching works left to right. Once a match is found the search starts again from the next character.

  If the same range is defined twice using the same syntax, only one range will be kept. Thus, "a-ca-c" creates only one range of "a-c".

  If the start and end of a range are in the wrong order, they are reversed. Thus "a-e" is the same as "e-a". As a result, "a-ee-a" would create only one range, as the "a-e" and "e-a" are the same.

  The set of characters represented is the union of the specified ranges.

  All CharSet objects returned by this method will be immutable.

  Parameters:

  setStrs - Strings to merge into the set, may be null

  Returns:

  a CharSet instance

  Since:

  2.4

• add

  protected void add(String str)

  Add a set definition string to the CharSet.

  Parameters:

  str - set definition string

• contains

  public boolean contains(char ch)

  Does the CharSet contain the specified character ch.

  Parameters:

  ch - the character to check for

  Returns:

  true if the set contains the characters

• equals

  public boolean equals(Object obj)

  Compares two CharSet objects, returning true if they represent exactly the same set of characters defined in the same way.

  The two sets abc and a-c are not equal according to this method.

  Overrides:

  equals in class Object

  Parameters:

  obj - the object to compare to

  Returns:

  true if equal

  Since:

  2.0

• hashCode

  public int hashCode()

  Gets a hash code compatible with the equals method.

  Overrides:

  hashCode in class Object

  Returns:

  a suitable hash code

  Since:

  2.0

• toString

  public String toString()

  Gets a string representation of the set.

  Overrides:

  toString in class Object

  Returns:

  string representation of the set