Package net.sf.saxon.regex

Class OpChoice

java.lang.Object
net.sf.saxon.regex.Operation
net.sf.saxon.regex.OpChoice
public class OpChoice extends Operation
A choice of several branches within a regular expression

  • Method Details

    • getMatchLength

      public int getMatchLength()
      Description copied from class: Operation
      Get the length of the matches returned by this operation if they are fixed-length
      Overrides:
      getMatchLength in class Operation
      Returns:
      the length of the matches, or -1 if the length is variable

    • getMinimumMatchLength

      public int getMinimumMatchLength()
      Description copied from class: Operation
      Get the minimum length of the matches returned by this operation
      Overrides:
      getMinimumMatchLength in class Operation
      Returns:
      the length of the shortest string that will match the operation

    • matchesEmptyString

      public int matchesEmptyString()
      Description copied from class: Operation
      Ask whether the regular expression is known, after static analysis, to match a zero-length string
      Specified by:
      matchesEmptyString in class Operation
      Returns:
      a value indicating whether the regex is statically known to match a zero-length string. Specifically: Returning 0 means that it is not known statically whether or not the regex will match a zero-length string; this case typically arises when back-references are involved.

    • containsCapturingExpressions

      public boolean containsCapturingExpressions()
      Description copied from class: Operation
      Ask whether the expression contains any capturing sub-expressions
      Overrides:
      containsCapturingExpressions in class Operation
      Returns:
      true if the expression contains any capturing sub-expressions (but not if it is a capturing expression itself, unless it contains nested capturing expressions)

    • getInitialCharacterClass

      public CharacterClass getInitialCharacterClass(boolean caseBlind)
      Description copied from class: Operation
      Get a CharacterClass identifying the set of characters that can appear as the first character of a non-empty string that matches this term. This is allowed to be an over-estimate (that is, the returned Character class must match every character that can legitimately appear at the start of the matched string, but it can also match other characters).
      Overrides:
      getInitialCharacterClass in class Operation
      Parameters:
      caseBlind - true if case-blind matching is in force ("i" flag)

    • getMaxLoopingDepth

      public int getMaxLoopingDepth()
      Get the maximum depth of looping within this operation
      Overrides:
      getMaxLoopingDepth in class Operation
      Returns:
      the maximum number of nested iterations

    • optimize

      public Operation optimize(REProgram program, REFlags flags)
      Description copied from class: Operation
      Optimize the operation
      Overrides:
      optimize in class Operation
      Parameters:
      program - the program being optimized
      flags - the regular expression flags
      Returns:
      the optimized operation

    • iterateMatches

      public IntIterator iterateMatches(REMatcher matcher, int position)
      Description copied from class: Operation
      Get an iterator returning all the matches for this operation
      Specified by:
      iterateMatches in class Operation
      Parameters:
      matcher - supplies the context for the matching; may be updated with information about captured groups
      position - the start position to seek a match
      Returns:
      an iterator returning the endpoints of all matches starting at the supplied position

    • display

      public String display()
      Display the operation as a regular expression, possibly in abbreviated form
      Specified by:
      display in class Operation
      Returns:
      the operation in a form that is recognizable as a regular expression or abbreviated regular expression