Interface Token


  • @InternalApi
    public interface Token
    A token is an individual element of a SQL statement.

    The available implementations of Token are primarily guided by the implementation of the tokenization and the needs of the parser and included visitors. It does not distinguish all types of tokens. For example there is QuotedIdentifierToken because the tokenization needs handling for quoted identifiers, while a normal identifier is a GenericToken, because that is handled by the fallback tokenization after checking for all other types. On the other hand, open and close curly braces, square brackets and parentheses each have their own type, as the parser may need this to find nested contexts.

    Since:
    5
    Author:
    Mark Rotteveel
    • Method Summary

      All Methods Instance Methods Abstract Methods Default Methods 
      Modifier and Type Method Description
      default void appendTo​(java.lang.StringBuilder sb)
      Appends the current token to the supplied String builder.
      default boolean equalsIgnoreCase​(java.lang.String tokenText)
      Case-insensitive equality of this tokens text using an equivalent of String.equalsIgnoreCase(String).
      default boolean isValidIdentifier()
      Detects if the token is valid as an identifier (ignoring length constraints).
      default boolean isWhitespaceOrComment()  
      int length()
      Token text length.
      int position()
      Token position.
      java.lang.String text()
      Token text.
      default java.lang.CharSequence textAsCharSequence()
      Token text as CharSequence.
    • Method Detail

      • text

        java.lang.String text()
        Token text.
        Returns:
        the text of the token; this is the original text from the source
        See Also:
        textAsCharSequence()
      • textAsCharSequence

        default java.lang.CharSequence textAsCharSequence()
        Token text as CharSequence.

        Default implementation returns text(). As an optimization, implementations may return their contained CharSequence to avoid unnecessary conversion to string.

        Returns:
        the text of the token; this is the original text from the source
        See Also:
        text()
      • appendTo

        default void appendTo​(java.lang.StringBuilder sb)
        Appends the current token to the supplied String builder.
        Parameters:
        sb - String builder to append to
      • position

        int position()
        Token position.
        Returns:
        0-based position of the occurrence of this token in the source (the first character)
      • length

        int length()
        Token text length.
        Returns:
        Length of the token text
      • isWhitespaceOrComment

        default boolean isWhitespaceOrComment()
        Returns:
        true if this token is whitespace or a comment, false for all other tokens
      • equalsIgnoreCase

        default boolean equalsIgnoreCase​(java.lang.String tokenText)
        Case-insensitive equality of this tokens text using an equivalent of String.equalsIgnoreCase(String).
        Parameters:
        tokenText - Token text to compare
        Returns:
        true if tokenText is equal - ignoring case - to the text of this token, false otherwise
      • isValidIdentifier

        default boolean isValidIdentifier()
        Detects if the token is valid as an identifier (ignoring length constraints).

        This will always return false for ReservedToken or other specialised tokens (e.g. OperatorToken with IS or LIKE) that can't occur as an identifier.

        Returns:
        true if the token is valid as an identifier, false otherwise