Package org.apache.poi.ss.formula.ptg

Class Ptg

  • All Implemented Interfaces:
    Serializable, Duplicatable, GenericRecord
    Direct Known Subclasses:
    ArrayPtg, ControlPtg, OperandPtg, OperationPtg, ScalarConstantPtg, UnknownPtg
    public abstract class Ptg
extends Object
implements Duplicatable, GenericRecord, Serializable
    Ptg represents a syntactic token in a formula. 'PTG' is an acronym for 'parse thing'. Originally, the name referred to the single byte identifier at the start of the token, but in POI, Ptg encapsulates the whole formula token (initial byte + value data).

    Ptgs are logically arranged in a tree representing the structure of the parsed formula. However, in BIFF files Ptgs are written/read in Reverse-Polish Notation order. The RPN ordering also simplifies formula evaluation logic, so POI mostly accesses Ptgs in the same way.

    See Also:
    Serialized Form

    • Constructor Detail

      • Ptg

        protected Ptg()

      • Ptg

        protected Ptg​(Ptg other)

    • Method Detail

      • readTokens

        public static Ptg[] readTokens​(int size,
                               LittleEndianInput in)
        Reads size bytes of the input stream, to create an array of Ptgs. Extra data (beyond size) may be read if and ArrayPtgs are present.

      • getEncodedSize

        public static int getEncodedSize​(Ptg[] ptgs)
        This method will return the same result as getEncodedSizeWithoutArrayData(Ptg[]) if there are no array tokens present.
        Returns:
        the full size taken to encode the specified Ptgs

      • getEncodedSizeWithoutArrayData

        public static int getEncodedSizeWithoutArrayData​(Ptg[] ptgs)
        Used to calculate value that should be encoded at the start of the encoded Ptg token array;
        Returns:
        the size of the encoded Ptg tokens not including any trailing array data.

      • getEncodedSizeWithoutArrayData

        public static int getEncodedSizeWithoutArrayData​(Ptg[] ptgs,
                                                 SpreadsheetVersion version)

      • serializePtgs

        public static int serializePtgs​(Ptg[] ptgs,
                                byte[] array,
                                int offset)
        Writes the ptgs to the data buffer, starting at the specified offset.
        The 2 byte encode length field is not written by this method.
        Returns:
        number of bytes written

      • serializePtgs

        public static int serializePtgs​(Ptg[] ptgs,
                                byte[] array,
                                int offset,
                                SpreadsheetVersion version)

      • getSize

        public abstract int getSize​(SpreadsheetVersion version)
        Returns:
        the encoded length of this Ptg, including the initial Ptg type identifier byte.

      • toFormulaString

        public abstract String toFormulaString()
        return a string representation of this token alone

      • setClass

        public final void setClass​(byte thePtgClass)

      • getPtgClass

        public final byte getPtgClass()
        Returns:
        the 'operand class' (REF/VALUE/ARRAY) for this Ptg

      • getRVAType

        public final char getRVAType()
        Debug / diagnostic method to get this token's 'operand class' type.
        Returns:
        'R' for 'reference', 'V' for 'value', 'A' for 'array' and '.' for base tokens

      • getDefaultOperandClass

        public abstract byte getDefaultOperandClass()

      • isBaseToken

        public abstract boolean isBaseToken()
        Returns:
        false if this token is classified as 'reference', 'value', or 'array'

      • doesFormulaReferToDeletedCell

        public static boolean doesFormulaReferToDeletedCell​(Ptg[] ptgs)

      • copy

        public abstract Ptg copy()
        Specified by:
        copy in interface Duplicatable
        Returns:
        a deep copy of the implementing class / instance

      • getSid

        public abstract byte getSid()
        Returns:
        structure id of the parsed thing, or -1 if the record has no sid