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
 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 context 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.
 java.lang.String getMatch()
          Returns the input text matched by the context immediately preceding the action expression that is currently being evaluated.
 int getMatchEndIndex()
          Returns the end index of the context 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 getMatchStartIndex()
          Returns the start index of the context immediately preceding the action expression that is currently being evaluated.
 Context<V> getParent()
          Returns the parent context, i.e.
 java.util.List<ParseError> getParseErrors()
          Returns the list of parse errors for the entire parsing run.
 MatcherPath getPath()
          Returns the MatcherPath to the currently running matcher.
 int getStartIndex()
          Returns the index into the underlying input buffer where the matcher of this context started its match.
 java.util.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()
          Returns true if this context or any sub node recorded a parse error.
 boolean inPredicate()
          Returns true if the current rule is running somewhere underneath a Test/TestNot rule.
 boolean isNodeSuppressed()
          Returns true if the current context is for or below a rule marked @SuppressNode or below one marked @SuppressSubnodes.
 

Method Detail

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

java.util.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

java.util.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()
Returns true 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

isNodeSuppressed

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

Returns:
true or false

hasError

boolean hasError()
Returns true 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

java.lang.String getMatch()

Returns the input text matched by the context 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 context 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 context 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 context 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

getValueStack

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

Returns:
the value stack