Package com.tangosol.coherence.dsltools.precedence

Class OPScanner

  • public class OPScanner
extends Object
    OPScanner gives clients a streaming api that returns a next OPToken by processing a java.lang.String using a TokenTable to convert lower level BaseTokens into the high functionality OPTokens. Since BaseTokens support a composite sequence token OPScanner supports nested scanning.
    Author:
    djl 2009.03.02

    • Field Detail

      • m_data

        protected BaseTokenStream m_data
        The source of BaseTokens to process

      • m_current

        protected BaseToken m_current
        The current BaseTokens from data

      • m_currentToken

        protected OPToken m_currentToken
        The current OPToken translated from current

      • m_tokenTable

        protected TokenTable m_tokenTable
        The TokenTable that defines the translation from BaseTokens to OPTokens

      • m_setOperators

        protected Set<CharSequence> m_setOperators
        The set of valid operators used by this scanner

    • Constructor Detail

      • OPScanner

        public OPScanner​(TokenTable tokenTable,
                 Set<CharSequence> setOperators)
        Construct a new OPScanner using the given TokenTable.
        Parameters:
        tokenTable - the TokenTable that defines the mapping from BaseTokens
        setOperators - the set of operators to use

    • Method Detail

      • scan

        public void scan​(String s)
        Initialize a new OPScanner to process the given String and load first token into current.
        Parameters:
        s - the String to convert to a stream of tokens

      • scan

        public void scan​(Reader r)
        Initialize a new OPScanner to process the given Reader and load first token into current.
        Parameters:
        r - the Reader to use as source for a stream of tokens

      • reset

        public void reset()
        Reset this scanner to process the current BaseTokenStream

      • setStrictness

        public void setStrictness​(boolean fStrict)
        The given flag determines the strictness in that an unknown token throws an exception otherwise they are turned into an identifier. The default setting is false.
        Parameters:
        fStrict - boolean to control the strictness

      • next

        public OPToken next()
        Move to the next token in the stream and return it.
        Returns:
        the current token

      • isEnd

        public boolean isEnd()
        If the Scanner is at the end answer true otherwise answer false.
        Returns:
        the boolean that answers as to whether the stream is atEnd

      • isEndOfStatement

        public boolean isEndOfStatement()
        If the scanner is at the end of a statement return true. A statement end is signified by either a semi-colon or the end of the token stream.
        Returns:
        true if the scanner is at the end of a statement

      • getCurrent

        public OPToken getCurrent()
        Answer the current OPToken.
        Returns:
        the current token

      • getCurrentBaseToken

        public BaseToken getCurrentBaseToken()
        Answer the current BaseToken.
        Returns:
        the current BaseToken

      • getCurrentAsString

        public String getCurrentAsString()
        Answer the string representation of the current BaseToken.
        Returns:
        the string representation of the current BaseToken

      • peekNextAsString

        public String peekNextAsString()
        Answer the string representation of the next BaseToken.
        Returns:
        the string representation of the next BaseToken

      • peekNext

        public BaseToken peekNext()
        Answer the string representation of the next BaseToken.
        Returns:
        the string representation of the next BaseToken

      • peekNext2AsStrings

        public String[] peekNext2AsStrings()
        Answer the String[] representation of the next two BaseTokens.
        Returns:
        the String[] representation of the next BaseToken

      • getCurrentAsStringWithAdvance

        public String getCurrentAsStringWithAdvance()
        Answer the string representation of the current BaseToken and advance.
        Returns:
        the string representation of the current BaseToken

      • matches

        public boolean matches​(String sWord)
        Test to see if the current BaseToken's string matches the given string. The token table's ignoringCase flag is consulted to see if case matters.
        Parameters:
        sWord - the string to match with
        Returns:
        a boolean indication of the success of the match

      • matches

        public boolean matches​(String sWord,
                       boolean fIgnoreCase)
        Test to see if the current BaseToken's string matches the given string. The given flag controls whether case is interesting.
        Parameters:
        sWord - the string to match with
        fIgnoreCase - the flag that indicates if case is interesting
        Returns:
        a boolean indication of the success of the match

      • advanceWhenMatching

        public boolean advanceWhenMatching​(String sWord)
        Test to see if the current BaseToken's string matches the given string and advance if true. * The token table's ignoringCase flag is consulted to see if case matters.
        Parameters:
        sWord - the string to match with
        Returns:
        a boolean indication of the success of the match

      • advance

        public OPToken advance​(String s)
        Advance to the next token and expect it to match the given string. If expectations are not met then throw an Exception. The token table's ignoringCase flag is consulted to see if case matters.
        Parameters:
        s - the string that should match the next token
        Returns:
        the next OPToken

      • advance

        public OPToken advance​(String s,
                       boolean fIgnoreCase)
        Advance to the next token and expect it to match the given string. If expectations are not met then throw an Exception. The given flag controls whether case is interesting.
        Parameters:
        s - the string that should match the next token
        fIgnoreCase - the flag that indicates if case is interesting
        Returns:
        the next OPToken

      • advance

        public OPToken advance()
        Advance to the next token.
        Returns:
        the next OPToken

      • pushStream

        public void pushStream​(BaseTokenStream ts)
        Remember the current BaseTokenStream and stream over the given stream.
        Parameters:
        ts - the BaseTokenStream to now stream over

      • popStream

        public void popStream()
        Restore the remembered BaseTokenStream as the source of streaming.

      • enableTokenNamed

        public void enableTokenNamed​(String name)
        Enable the token named by the given string.
        Parameters:
        name - the name of the OPToken to enable

      • disableTokenNamed

        public void disableTokenNamed​(String name)
        Disable the token named by the given string.
        Parameters:
        name - the name of the OPToken to disable

      • classify

        protected OPToken classify()
        Figure out how to map the current BaseToken to a OPToken and return it.
        Returns:
        the current OPToken