I'm not entirely sure whether it will help for the reading and writing formulas. This might help for the evaluator. Please take a good look at HSSF and see how you'd patch it. What we really need is a Excel formula notation -> RPN converter and vice versa. However the RPN has got to be based on Excel's tokens.
-Andy On Sat, 2002-04-13 at 12:11, Jocelyn Paine wrote: > What's the status of formula support? There are recent messages saying > it's in an early stage of development: message from Andy Oliver on March > 7th suggests you still have to write the parser. > > I've been developing a spreadsheet compiler/decompiler, and as part of > this, I have code to read and write SLK files. These are a lot simpler > than XLS (basically, one command per line, plain text and standard > notation for formulae, plus a few special tags), but perhaps my code could > be useful to you? > > The parser is written with the JavaCC parser-generator, see > http://www.webgain.com/products/java_cc/ . This is relatively easy to use > - standard declarative notation for syntax, plus semantic rules written in > Java - and comes with a number of examples. It's also free. I parse > formulae into trees, the standard way to represent expressions in compiler > writing. I've also written a module that converts these trees back into > strings, used when writing the formulae back out. > > If any of this is useful, I'm happy to donate the code. It would need some > adapting, but it would get you a fair way there, especially with the > parser. One of the things I've used it for is an 'Autopublisher' to which > one can submit spreadsheets and have them automatically converted into Web > pages plus server-side code to evaluate the spreadsheet. This reads SLK > files and uses the formulae in several ways: to be analysed for cell > dependencies, to be evaluated, and to be decompiled into a summary of the > calculations, so shows that my representation can be used in a variety of > ways. > > Jocelyn Paine > http://www.ifs.org.uk/~popx/ > > Spreadsheet Autopublisher: > http://www.bized.ac.uk/virtual/vla/autopublisher/ > > Model Master spreadsheet tools: > http://www.ifs.org.uk/~popx/mm_publications.html > > -- http://www.superlinksoftware.com http://jakarta.apache.org/poi - port of Excel/Word/OLE 2 Compound Document format to java http://developer.java.sun.com/developer/bugParade/bugs/4487555.html - fix java generics! The avalanche has already started. It is too late for the pebbles to vote. -Ambassador Kosh
