Package com.itextpdf.io.font.otf

Class ContextualTableContextualRule>

java.lang.Object
com.itextpdf.io.font.otf.ContextualTable
Type Parameters:
T - the contextual rule type stored by this table
Direct Known Subclasses:
ChainingContextualTable, PosTableLookup7Format2, SubTableLookup5Format1, SubTableLookup5Format2, SubTableLookup5Format3
public abstract class ContextualTableContextualRule> extends Object
Represents the contextual table of an OpenType font.

  • Field Details

    • openReader

      protected OpenTypeFontTableReader openReader
      Stores open reader.

    • lookupFlag

      protected int lookupFlag
      Specifies processing options, e.g. whether to skip base glyphs, marks or ligatures during glyph substitution or positioning. See Lookup table

  • Constructor Details

    • ContextualTable

      protected ContextualTable (OpenTypeFontTableReader openReader, int lookupFlag)
      Creates a new contextual table.
      Parameters:
      openReader - the OpenType font reader
      lookupFlag - specifies processing options, e.g. whether to skip base glyphs, marks or ligatures during glyph substitution or positioning. See Lookup table

  • Method Details

    • getMatchingContextRule

      public T getMatchingContextRule (GlyphLine line)
      Gets a most preferable context rule that matches the line at current position. If no matching context rule is found, it returns null.

      NOTE: if matching context rule is found, the GlyphLine.start and GlyphLine.end will be changed in such way that they will point at start and end of the matching context glyph sequence inside the glyph line.
      Parameters:
      line - a line, which is to be checked if it matches some context.
      Returns:
      matching context rule or null, if none was found.

    • getSetOfRulesForStartGlyph

      protected abstract List<T> getSetOfRulesForStartGlyph (int startId)
      Gets a set of rules, which start with given glyph id.
      Parameters:
      startId - id of the first glyph in the sequence
      Returns:
      a list of ContextualSubstRule instances. The list will be empty if there are no rules that start with a given glyph id

    • checkIfContextMatch

      protected int checkIfContextMatch (GlyphLine line, T rule)
      Checks if given glyph line matches given rule.
      Parameters:
      line - glyph line to be checked
      rule - rule to be compared with a given glyph line
      Returns:
      either index which corresponds to the last glyph of the matching context inside the glyph line if context matches, or -1 if context doesn't match