Java GDSII API (JGDS) 

Package com.ohrasys.cad.gds Description

Provides a set of objects that can be used to import, create and export GDSII database records. GDSII is the primary format used to transfer physical data representing circuit layout generated from EDA/CAD tools . The GDSII stream format is originally based on the CALMA format which is now obsolete. Below is a Bachus Naur representation of the GDSII stream syntax.

                                    <stream>     :: 
                                    HEADER BGNLIB [LIBDIRSIZE] [SRFNAME] [LIBSECUR]
                                    LIBNAME [REFLIBS] [FONTS] [ATTRTABLE]
                                    [GENERATIONS] [<formattype>] UNITS {<structure>}*
                                    ENDLIB

                                    <formattype> :: 
                                    FORMAT | FORMAT {MASK}+ ENDMASKS

                                    <structure>  :: 
                                    BGNSTR STRNAME [STRCLASS] {<element>}* ENDSTR

                                    <element>  :: 
                                    {<boundary> | <path> | <sref> | <aref> | 
                                    <text> | <node> | <box>} {<property>}*

                                    <boundary>  :: 
                                    BOUNDARY [ELFLAGS] [PLEX] LAYER DATATYPE XY
      
                                    <path>  :: 
                                    PATH  [ELFLAGS] [PLEX] LAYER DATATYPE [PATHTYPE] [WIDTH] [BGNEXTN]
                                    [ENDEXTN] XY

                                    <sref>  :: 
                                    SREF [ELFLAGS] [PLEX] SNAME [<strans>] XY

                                    <aref>  :: 
                                    AREF [ELFLAGS] [PLEX] SNAME [<strans>] COLROW XY

                                    <text>  :: 
                                    TEXT [ELFLAGS] [PLEX] LAYER <textbody>

                                    <node>  :: 
                                    NODE [ELFLAGS] [PLEX] LAYER NODETYPE XY

                                    <box>  :: 
                                    BOX [ELFLAGS] [PLEX] LAYER BOXTYPE XY

                                    <textbody>  :: 
                                    TEXTTYPE [PRESENTATION] [PATHTYPE] [WIDTH] [<strans>] XY STRING

                                    <strans>  :: 
                                    STRANS [MAG] [ANGLE]

                                    <property>  :: 
                                    PROPATTR PROPVALUE
                                

Please see The GDSII techincal reference for a more complete discussion of the GDSII stream syntax.

Example Code Snippet

  public List parseDesign(InputStream in, OutputStream out) {
    GDSStatistics stats = new GDSStatistics();
    DatabaseValidator isValid = new DatabaseValidator();
    boolean resultVld = true;
    List records = new ArrayList(estimateSize(in));
    stats.clear();
    isValid.reset();
    GDSRecord      record = null;
    GDSInputStream gdsin  = new GDSInputStream(in);
    try {
      while((record = gdsin.readRecord()) != null) {
        try {
          if(isValid.test(record.getRectype()) == isValid.FAILED)
            throw new GDSRecordException("Test failed");
        } catch(BNFTestException e) {
          throw new GDSRecordException(e.getMessage());
        }
        stats.record(record);
        records.add(record);
        if(record.getRectype() != GDSRecord.NULL)
          write(record.toString(), out);
      }
    } catch(GDSRecordException e) {
      write(e.getMessage(), out);
      resultVld = false;
    }
    close();
    if(resultVld)
    {return records;} else
    {return null;}
  }