Package org.parboiled

Interface Context<V>

All Known Implementing Classes:
MatcherContext
public interface Context<V>
A Context object is available to parser actions methods during their runtime and provides various support functionalities.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    fastStringMatching()
    Returns true if fast string matching is enabled for this parsing run.
    char
    getCurrentChar()
    Returns the character at the current index..
    int
    getCurrentIndex()
    Returns the current index in the input buffer.
    char
    getFirstMatchChar()
    Returns the first character of the input text matched by the rule immediately preceding the action expression that is currently being evaluated.
    InputBuffer
    getInputBuffer()
    Returns the InputBuffer the parser is currently running against
    int
    getLevel()
    Returns the current matcher level, with 0 being the root level, 1 being one level below the root and so on.
    String
    getMatch()
    Returns the input text matched by the rule immediately preceding the action expression that is currently being evaluated.
    int
    getMatchEndIndex()
    Returns the end index of the rule immediately preceding the action expression that is currently being evaluated.
    Matcher
    getMatcher()
    Returns the Matcher of this context or null, if this context is not valid anymore.
    int
    getMatchLength()
    Returns the number of characters matched by the rule immediately preceding the action expression that is currently being evaluated.
    IndexRange
    getMatchRange()
    Creates a new IndexRange instance covering the input text matched by the rule immediately preceding the action expression that is currently being evaluated.
    int
    getMatchStartIndex()
    Returns the start index of the rule immediately preceding the action expression that is currently being evaluated.
    Context<V>
    getParent()
    Returns the parent context, i.e.
    List<ParseError>
    getParseErrors()
    Returns the list of parse errors for the entire parsing run.
    MatcherPath
    getPath()
    Returns the MatcherPath to the currently running matcher.
    Position
    getPosition()
    Returns the current position in the underlying InputBuffer as a Position instance.
    int
    getStartIndex()
    Returns the index into the underlying input buffer where the matcher of this context started its match.
    List<Node<V>>
    getSubNodes()
    Returns the parse tree subnodes already created in the current context scope.
    ValueStack<V>
    getValueStack()
    Returns the value stack instance used during this parsing run.
    boolean
    hasError()
    Determines if this context or any sub node recorded a parse error.
    boolean
    inErrorRecovery()
    Determines if the action calling this method is run during the resynchronization phase of an error recovery.
    boolean
    inPredicate()
    Determines if the current rule is running somewhere underneath a Test/TestNot rule.
    boolean
    isNodeSuppressed()
    Determines if the current context is for or below a rule marked @SuppressNode or below one marked @SuppressSubnodes.

  • Method Details

    • getParent

      Context<V> getParent()
      Returns the parent context, i.e. the context for the currently running parent matcher.
      Returns:
      the parent context

    • getInputBuffer

      InputBuffer getInputBuffer()
      Returns the InputBuffer the parser is currently running against
      Returns:
      the InputBuffer

    • getMatcher

      Matcher getMatcher()
      Returns the Matcher of this context or null, if this context is not valid anymore.
      Returns:
      the matcher

    • getStartIndex

      int getStartIndex()
      Returns the index into the underlying input buffer where the matcher of this context started its match.
      Returns:
      the start index

    • getCurrentIndex

      int getCurrentIndex()
      Returns the current index in the input buffer.
      Returns:
      the current index

    • getCurrentChar

      char getCurrentChar()
      Returns the character at the current index..
      Returns:
      the current character

    • getParseErrors

      List<ParseError> getParseErrors()
      Returns the list of parse errors for the entire parsing run.
      Returns:
      the list of parse errors

    • getPath

      MatcherPath getPath()
      Returns the MatcherPath to the currently running matcher.
      Returns:
      the path

    • getLevel

      int getLevel()
      Returns the current matcher level, with 0 being the root level, 1 being one level below the root and so on.
      Returns:
      the current matcher level

    • fastStringMatching

      boolean fastStringMatching()

      Returns true if fast string matching is enabled for this parsing run.

      Fast string matching "short-circuits" the default practice of treating string rules as simple Sequence of character rules. When fast string matching is enabled strings are matched at once, without relying on inner CharacterMatchers. Even though this can lead to significant increases of parsing performance it does not play well with error reporting and recovery, which relies on character level matches. Therefore the ReportingParseRunner and RecoveringParseRunner implementations only enable fast string matching during their basic first parsing run and disable it once the input has proven to contain errors.

      Returns:
      true if fast string matching is enabled during the current parsing run

    • getSubNodes

      List<Node<V>> getSubNodes()
      Returns the parse tree subnodes already created in the current context scope. Note that the returned list is immutable.
      Returns:
      the parse tree subnodes already created in the current context scope

    • inPredicate

      boolean inPredicate()
      Determines if the current rule is running somewhere underneath a Test/TestNot rule.
      Returns:
      true if the current context has a parent which corresponds to a Test/TestNot rule

    • inErrorRecovery

      boolean inErrorRecovery()
      Determines if the action calling this method is run during the resynchronization phase of an error recovery.
      Returns:
      true if the action calling this method is run during the resynchronization phase of an error recovery

    • isNodeSuppressed

      boolean isNodeSuppressed()
      Determines if the current context is for or below a rule marked @SuppressNode or below one marked @SuppressSubnodes.
      Returns:
      true or false

    • hasError

      boolean hasError()
      Determines if this context or any sub node recorded a parse error.
      Returns:
      true if this context or any sub node recorded a parse error

    • getMatch

      String getMatch()

      Returns the input text matched by the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.

      Returns:
      the input text matched by the immediately preceding subcontext

    • getFirstMatchChar

      char getFirstMatchChar()

      Returns the first character of the input text matched by the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.

      If the immediately preceding rule did not match anything this method throws a GrammarException. If you need to able to handle that case use the getMatch() method.

      Returns:
      the input text matched by the immediately preceding subcontext

    • getMatchStartIndex

      int getMatchStartIndex()

      Returns the start index of the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.

      Returns:
      the start index of the context immediately preceding current action

    • getMatchEndIndex

      int getMatchEndIndex()

      Returns the end index of the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.

      Returns:
      the end index of the context immediately preceding current action, i.e. the index of the character immediately following the last matched character

    • getMatchLength

      int getMatchLength()

      Returns the number of characters matched by the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.

      Returns:
      the number of characters matched

    • getPosition

      Position getPosition()

      Returns the current position in the underlying InputBuffer as a Position instance.

      Returns:
      the current position in the underlying inputbuffer

    • getMatchRange

      IndexRange getMatchRange()
      Creates a new IndexRange instance covering the input text matched by the rule immediately preceding the action expression that is currently being evaluated. This call can only be used in actions that are part of a Sequence rule and are not at first position in this Sequence.
      Returns:
      a new IndexRange instance

    • getValueStack

      ValueStack<V> getValueStack()
      Returns the value stack instance used during this parsing run.
      Returns:
      the value stack