New (StringTokenizer constructor): Difference between revisions

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Create new StringTokenizer object (StringTokenizer class)


This method returns a new instance of a StringTokenizer object. It has three optional arguments that let you specify the delimiter characters that determine the tokens in the string that is being tokenized.

Syntax

%stringTokenizer = [%(StringTokenizer):]New[( [TokenChars= string], - [Spaces= string], - [Quotes= string], - [Separators= string])]

Syntax terms

%stringTokenizer A StringTokenizer object expression to contain the new object instance.
[%(StringTokenizer):] The optional class name in parentheses denotes a Constructor. See "Usage notes", below, for more information about invoking a StringTokenizer Constructor.
TokenChars This name required string argument TokenChars is a set of single-character token-delimiters (delimiters that are also tokens) that may be separated by whitespace characters. TokenChars is an optional argument that defaults to a null string.
Spaces This name required string argument Spaces is a set of "whitespace" characters, that is, characters that separate tokens. Each of these characters is a "non-token delimiter," a delimiter that is not itself a token. Spaces is an optional argument that defaults to a blank character.
Quotes This name required string argument Quotes is a set of quotation characters. The text between each disjoint pair of identical quotation characters (a "quoted region") is treated as a single token, and any delimiter characters (Quote, Space, or TokenChar) within a quoted region are treated as non-delimiters. Quotes is an optional argument that defaults to a null string.

Usage notes

  • As described in "Using New or other Constructors", New can be invoked with no object, with an explicit class name, or with an object variable in the class, even if that object is Null:

    %stringTokenizer = new %stringTokenizer = %(StringTokenizer):new %stringTokenizer = %stringTokenizer:new

  • A character may belong to at most one of the Spaces, Quotes, or TokenChars sets of characters.
  • If you are specifying Spaces, Quotes, or TokenChars, each character in the string is a quotation character — that is, you may not separate characters — and no character may repeat (except for apostrophe, which may be doubled).
  • A quoted region is not affected by the TokensToLower and TokensToUpper properties.

Examples

In the following request, a variety of delimiters is on display:

begin %tok is object stringtokenizer %tok = new(spaces=' ;', tokenchars='=_', quotes='"') %tok:string = '--=_alternative 0016B5A2CA2574DD_=; - Content-Type: text/plain; charset="US-ASCII"' repeat while not %tok:atEnd printText {~} is {%tok:nextToken} end repeat end

The result is:

%tok:nextToken is -- %tok:nextToken is = %tok:nextToken is _ %tok:nextToken is alternative %tok:nextToken is 0016B5A2CA2574DD %tok:nextToken is _ %tok:nextToken is = %tok:nextToken is Content-Type: %tok:nextToken is text/plain %tok:nextToken is charset %tok:nextToken is = %tok:nextToken is US-ASCII

See also