Class CMapAwareDocumentFont


  • public class CMapAwareDocumentFont
    extends DocumentFont
    Implementation of DocumentFont used while parsing PDF streams.
    Since:
    2.1.4
    • Field Detail

      • spaceWidth

        private int spaceWidth
        the width of a space for this font, in normalized 1000 point units
      • toUnicodeCmap

        private CMap toUnicodeCmap
        The CMap constructed from the ToUnicode map from the font's dictionary, if present. This CMap transforms CID values into unicode equivalent
      • cidbyte2uni

        private char[] cidbyte2uni
        Mapping between CID code (single byte only for now) and unicode equivalent as derived by the font's encoding. Only needed if the ToUnicode CMap is not provided.
    • Constructor Detail

      • CMapAwareDocumentFont

        public CMapAwareDocumentFont​(PRIndirectReference refFont)
        Creates an instance of a CMapAwareFont based on an indirect reference to a font.
        Parameters:
        refFont - the indirect reference to a font
    • Method Detail

      • processToUnicode

        private void processToUnicode()
        Parses the ToUnicode entry, if present, and constructs a CMap for it
        Since:
        2.1.7
      • processUni2Byte

        private void processUni2Byte()
        Inverts DocumentFont's uni2byte mapping to obtain a cid-to-unicode mapping based on the font's encoding
        Since:
        2.1.7
      • computeAverageWidth

        private int computeAverageWidth()
        For all widths of all glyphs, compute the average width in normalized 1000 point units. This is used to give some meaningful width in cases where we need an average font width (such as if the width of a space isn't specified by a given font)
        Returns:
        the average width of all non-zero width glyphs in the font
      • getWidth

        public int getWidth​(int char1)
        Description copied from class: DocumentFont
        Gets the width of a char in normalized 1000 units.
        Overrides:
        getWidth in class DocumentFont
        Parameters:
        char1 - the unicode char to get the width of
        Returns:
        the width in normalized 1000 units
        Since:
        2.1.5 Override to allow special handling for fonts that don't specify width of space character
        See Also:
        DocumentFont.getWidth(int)
      • decodeSingleCID

        private java.lang.String decodeSingleCID​(byte[] bytes,
                                                 int offset,
                                                 int len)
        Decodes a single CID (represented by one or two bytes) to a unicode String.
        Parameters:
        bytes - the bytes making up the character code to convert
        offset - an offset
        len - a length
        Returns:
        a String containing the encoded form of the input bytes using the font's encoding.
      • hasUnicodeCMAP

        public boolean hasUnicodeCMAP()
        Returns:
        true if this font has unicode information available.
      • hasTwoByteUnicodeCMAP

        public boolean hasTwoByteUnicodeCMAP()
        Returns:
        true if this font has unicode information available and if it is two bytes.
      • decode

        public java.lang.String decode​(byte[] cidbytes,
                                       int offset,
                                       int len)
        Decodes a string of bytes (encoded in the font's encoding) into a unicode string. This will use the ToUnicode map of the font, if available, otherwise it uses the font's encoding
        Parameters:
        cidbytes - the bytes that need to be decoded
        len - length
        offset - offset
        Returns:
        the unicode String that results from decoding
        Since:
        2.1.7
      • decode

        public java.lang.String decode​(java.lang.String chars)
        Decodes a string. This is a normal Java string, but if the range of character values exceeds the range of the encoding for the font, this will fail. Required since we need to process the characters of strings, and we can't determine the character boundaries in advance, especially because of Identity-H encoded fonts which have two-byte character indexes.

        PdfString is used to hold character code points, even though the bytes may not map 1-1. It's not possible to change the encoding once a string is in place.

        Parameters:
        chars - the Characters that need to be decoded
        Returns:
        the unicode String that results from decoding
        Since:
        2.1.
      • decode

        public java.lang.String decode​(char c)
                                throws java.lang.Error
        Decode single character whose value represents a code point in this font. Will fail if the characters do not have values that correspond to valid code points for the font.
        Parameters:
        c - character to decode
        Returns:
        Unicode character corresponding to the remapped code according to the font's current encoding.
        Throws:
        java.lang.Error - if the the character is out of range