Java tutorial
/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* * AssociatorEvaluation.java * Copyright (C) 2006 University of Waikato, Hamilton, New Zealand */ package cba; import weka.core.Instances; import weka.core.Option; import weka.core.OptionHandler; import weka.core.RevisionHandler; import weka.core.RevisionUtils; import weka.core.Utils; import weka.core.Drawable; import weka.core.converters.ConverterUtils.DataSource; import java.util.Enumeration; import java.io.BufferedWriter; import java.io.FileWriter; /** * Class for evaluating Associaters. * * @author fracpete (fracpete at waikato dot ac dot nz) * @version $Revision: 1.5 $ */ public class AssociatorEvaluation implements RevisionHandler { /** the result string */ protected StringBuffer m_Result; /** * default constructor */ public AssociatorEvaluation() { super(); m_Result = new StringBuffer(); } /** * Generates an option string to output on the commandline. * * @param associator the associator to generate the string for * @return the option string */ protected static String makeOptionString(Associator associator) { StringBuffer text; text = new StringBuffer(); // general options text.append("\nGeneral options:\n\n"); text.append("-t <training file>\n"); text.append("\tThe name of the training file.\n"); text.append("-g <name of graph file>\n"); text.append("\tOutputs the graph representation (if supported) of the associator to a file.\n"); // associator specific options, if any if (associator instanceof OptionHandler) { text.append( "\nOptions specific to " + associator.getClass().getName().replaceAll(".*\\.", "") + ":\n\n"); Enumeration enm = ((OptionHandler) associator).listOptions(); while (enm.hasMoreElements()) { Option option = (Option) enm.nextElement(); text.append(option.synopsis() + "\n"); text.append(option.description() + "\n"); } } return text.toString(); } /** * Evaluates an associator with the options given in an array of strings. * * @param associatorString class of associator as a string * @param options the array of string containing the options * @throws Exception if model could not be evaluated successfully * @return a string describing the results */ public static String evaluate(String associatorString, String[] options) throws Exception { Associator associator; // Create associator try { associator = (Associator) Class.forName(associatorString).newInstance(); } catch (Exception e) { throw new Exception("Can't find class with name " + associatorString + '.'); } return evaluate(associator, options); } /** * Evaluates the associator with the given commandline options and returns * the evaluation string. * * @param associator the Associator to evaluate * @param options the commandline options * @return the generated output string * @throws Exception if evaluation fails */ public static String evaluate(Associator associator, String[] options) throws Exception { String trainFileString = ""; String graphFileName = ""; AssociatorEvaluation eval; DataSource loader; // help? if (Utils.getFlag('h', options)) throw new Exception("\nHelp requested.\n" + makeOptionString(associator)); try { // general options trainFileString = Utils.getOption('t', options); if (trainFileString.length() == 0) throw new Exception("No training file given!"); loader = new DataSource(trainFileString); graphFileName = Utils.getOption('g', options); // associator specific options if (associator instanceof OptionHandler) { ((OptionHandler) associator).setOptions(options); } // left-over options? Utils.checkForRemainingOptions(options); } catch (Exception e) { throw new Exception("\nWeka exception: " + e.getMessage() + "\n" + makeOptionString(associator)); } // load file and build associations eval = new AssociatorEvaluation(); String results = eval.evaluate(associator, new Instances(loader.getDataSet())); // If associator is drawable output string describing graph if ((associator instanceof Drawable) && (graphFileName.length() != 0)) { BufferedWriter writer = new BufferedWriter(new FileWriter(graphFileName)); writer.write(((Drawable) associator).graph()); writer.newLine(); writer.flush(); writer.close(); } return results; } /** * Evaluates the associator with the given commandline options and returns * the evaluation string. * * @param associator the Associator to evaluate * @param data the data to run the associator with * @return the generated output string * @throws Exception if evaluation fails */ public String evaluate(Associator associator, Instances data) throws Exception { long startTime; long endTime; // build associations startTime = System.currentTimeMillis(); associator.buildAssociations(data); endTime = System.currentTimeMillis(); m_Result = new StringBuffer(associator.toString()); m_Result.append("\n=== Evaluation ===\n\n"); m_Result.append("Elapsed time: " + (((double) (endTime - startTime)) / 1000) + "s"); m_Result.append("\n"); return m_Result.toString(); } /** * Tests whether the current evaluation object is equal to another * evaluation object * * @param obj the object to compare against * @return true if the two objects are equal */ public boolean equals(Object obj) { if ((obj == null) || !(obj.getClass().equals(this.getClass()))) return false; AssociatorEvaluation cmp = (AssociatorEvaluation) obj; // TODO: better comparison??? String associatingResults1 = m_Result.toString().replaceAll("Elapsed time.*", ""); String associatingResults2 = cmp.m_Result.toString().replaceAll("Elapsed time.*", ""); if (!associatingResults1.equals(associatingResults2)) return false; return true; } /** * returns a summary string of the evaluation with a no title * * @return the summary string */ public String toSummaryString() { return toSummaryString(""); } /** * returns a summary string of the evaluation with a default title * * @param title the title to print before the result * @return the summary string */ public String toSummaryString(String title) { StringBuffer result; result = new StringBuffer(title); if (title.length() != 0) result.append("\n"); result.append(m_Result); return result.toString(); } /** * returns the current result * * @return the currently stored result * @see #toSummaryString() */ public String toString() { return toSummaryString(); } /** * Returns the revision string. * * @return the revision */ public String getRevision() { return RevisionUtils.extract("$Revision: 1.5 $"); } /** * A test method for this class. Just extracts the first command line * argument as an associator class name and calls evaluate. * * @param args an array of command line arguments, the first of which * must be the class name of an associator. */ public static void main(String[] args) { try { if (args.length == 0) { throw new Exception("The first argument must be the class name of a kernel"); } String associator = args[0]; args[0] = ""; System.out.println(evaluate(associator, args)); } catch (Exception ex) { ex.printStackTrace(); System.err.println(ex.getMessage()); } } }