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/**
* The ObjectBank class is designed to make it easy to change the format/source
* of data read in by other classes and to standardize how data is read in javaNLP
* classes. This should make reuse of existing code (by non-authors of the code)
* easier because one has to just create a new ObjectBank which knows where to
* look for the data and how to turn it into Objects, and then use the new
* ObjectBank in the class. This will also make it easier to reuse code for
* reading in the same data.
*
* An ObjectBank is a Collection of Objects. These objects are taken
* from input sources and then tokenized and parsed into the desired
* kind of Object. An ObjectBank requires a ReaderIteratorFactory and an
* IteratorFromReaderFactory. The ReaderIteratorFactory is used to get
* an Iterator over java.util.Readers which contain representations of
* the Objects. A ReaderIteratorFactory resembles a Collection that
* takes input sources and dispenses Iterators over java.util.Readers
* of those sources. An IteratorFromReaderFactory is used to turn a single
* java.util.Reader into an Iterator over Objects. The IteratorFromReaderFactory
* splits the contents of the java.util.Reader into Strings and then parses them
* into appropriate Objects.
*
* Example Usage:
*
* You have a collection of files in the directory /u/nlp/data/gre/questions. Each file
* contains several Puzzle documents which look like:
*
* <puzzle>
* <preamble> some text </preamble>
* <question> some intro text
* <answer> answer1 </answer>
* <answer> answer2 </answer>
* <answer> answer3 </answer>
* <answer> answer4 </answer>
* </question>
* <question> another question
* <answer> answer1 </answer>
* <answer> answer2 </answer>
* <answer> answer3 </answer>
* <answer> answer4 </answer>
* </question>
* </puzzle>
*
*
* First you need to build a ReaderIteratorFactory which will provide java.io.Readers
* over all the files in your directory:
*
*
* Next you need to make a IteratorFromReaderFactory which will take the java.io.Readers * vended by the ReaderIteratorFactory, split them up into documents (Strings) and * then convert the Strings into Objects. In this case we want to keep everything * between each set of <puzzle> </puzzle> tags so we would use a BeginEndIteratorFactory. * You would also need to write a class which extends Appliable and whose apply method * converts the String between the <puzzle> </puzzle> tags into Puzzle objects. * *
* public class PuzzleParser implements Appliable {
* public Object apply (Object o) {
* String s = (String)o;
* ...
* Puzzle p = new Puzzle(...);
* ...
* return p;
*
*
* Now to build the IteratorFromReaderFactory:
*
*
* IteratorFromReaderFactory rtif = BeginEndIterator.getFactory("<puzzle>", "</puzzle>", new PuzzleParser());
*
*
* Now, to create your ObjectBank you just give it the ReaderIteratorFactory and
* IteratorFromReaderFactory that you just created:
*
* * ObjectBank puzzles = new ObjectBank(rif, rtif); ** * Now, if you get a new set of puzzles that are located elsewhere and formatted differently * you create a new ObjectBank for reading them in and use that ObjectBank instead with only * trivial changes (or possible none at all if the ObjectBank is read in on a constructor) * to your code. Or even better, if someone else wants to use your code to evaluate their puzzles, * which are located elsewhere and formatted differently, they already know what they have to do * to make your code work for them. */ package edu.stanford.nlp.objectbank;