content: /*
   *    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.
   */
  
  /*
   *    CSVResultListener.java
   *    Copyright (C) 1999 University of Waikato, Hamilton, New Zealand
   *
   */
  
  
  package weka.experiment;
  
  import weka.core.Option;
  import weka.core.OptionHandler;
  import weka.core.RevisionHandler;
  import weka.core.RevisionUtils;
  import weka.core.Utils;
  
  import java.io.BufferedOutputStream;
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.PrintWriter;
  import java.util.Enumeration;
  import java.util.Vector;
  
  /**
   <!-- globalinfo-start -->
   * Takes results from a result producer and assembles them into comma separated value form.
   * <p/>
   <!-- globalinfo-end -->
   *
   <!-- options-start -->
   * Valid options are: <p/>
   * 
   * <pre> -O &lt;file name&gt;
   *  The filename where output will be stored. Use - for stdout.
   *  (default temp file)</pre>
   * 
   <!-- options-end -->
   * 
   * @author Len Trigg (trigg@cs.waikato.ac.nz)
   * @version $Revision: 1.13 $
   */
  public class CSVResultListener 
    implements ResultListener, OptionHandler, RevisionHandler {
    
    /** for serialization */
    static final long serialVersionUID = -623185072785174658L;
  
    /** The ResultProducer sending us results */
    protected ResultProducer m_RP;
  
    /** The destination output file, null sends to System.out */
    protected File m_OutputFile = null;
  
    /** The name of the output file. Empty for temporary file. */
    protected String m_OutputFileName = "";
  
    /** The destination for results (typically connected to the output file) */
    protected transient PrintWriter m_Out = new PrintWriter(System.out, true);
  
    /** 
     * Sets temporary file.
     */
    public CSVResultListener() {
  
      File resultsFile;
      try {
        resultsFile = File.createTempFile("weka_experiment", ".csv");
        resultsFile.deleteOnExit();
      } catch (Exception e) {
        System.err.println("Cannot create temp file, writing to standard out.");
        resultsFile = new File("-");
      }
      setOutputFile(resultsFile);
      setOutputFileName("");
    }
  
    /**
     * Returns a string describing this result listener
     * @return a description of the result listener suitable for
     * displaying in the explorer/experimenter gui
     */
    public String globalInfo() {
      return "Takes results from a result producer and assembles them into "
        +"comma separated value form.";
    }
  
    /**
     * Returns an enumeration describing the available options..
     *
     * @return an enumeration of all the available options.
     */
    public Enumeration listOptions() {
  
      Vector newVector = new Vector(1);
  
      newVector.addElement(new Option(
  	     "\tThe filename where output will be stored. Use - for stdout.\n"
  	      +"\t(default temp file)", 
  	     "O", 1, 
  	     "-O <file name>"));
  
      return newVector.elements();
    }
  
    /**
     * Parses a given list of options. <p/>
     *
     <!-- options-start -->
     * Valid options are: <p/>
     * 
     * <pre> -O &lt;file name&gt;
     *  The filename where output will be stored. Use - for stdout.
     *  (default temp file)</pre>
     * 
     <!-- options-end -->
     *
     * @param options the list of options as an array of strings
     * @throws Exception if an option is not supported
     */
    public void setOptions(String[] options) throws Exception {
      
      String fName = Utils.getOption('O', options);
      if (fName.length() != 0) {
        setOutputFile(new File(fName));
      } else {
        File resultsFile;
        try {
  	resultsFile = File.createTempFile("weka_experiment", null);
  	resultsFile.deleteOnExit();
        } catch (Exception e) {
  	System.err.println("Cannot create temp file, writing to standard out.");
  	resultsFile = new File("-");
        }
        setOutputFile(resultsFile);
        setOutputFileName("");
      }
    }
  
    /**
     * Gets the current settings of the Classifier.
     *
     * @return an array of strings suitable for passing to setOptions
     */
    public String [] getOptions() {
  
      String [] options = new String [2];
      int current = 0;
  
      options[current++] = "-O";
      options[current++] = getOutputFile().getName();
      while (current < options.length) {
        options[current++] = "";
      }
      return options;
    }
  
    /**
     * Returns the tip text for this property
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String outputFileTipText() {
      return "File to save to. Use '-' to write to standard out.";
    }
  
    /**
     * Get the value of OutputFile.
     *
     * @return Value of OutputFile.
     */
    public File getOutputFile() {
      
      return m_OutputFile;
    }
    
    /**
     * Set the value of OutputFile. Also sets the
     * OutputFileName.
     *
     * @param newOutputFile Value to assign to OutputFile.
     */
    public void setOutputFile(File newOutputFile) {
      
      m_OutputFile = newOutputFile;
      setOutputFileName(newOutputFile.getName());
    }
  
    /**
     * Get the value of OutputFileName.
     *
     * @return Value of OutputFile.
     */
    public String outputFileName() {
      
      return m_OutputFileName;
    }
  
    /**
     * Set the value of OutputFileName. Must be used
     * AFTER setOutputFile.
     *
     * @param name the name of OutputFile.
     */
    public void setOutputFileName(String name) {
      
      m_OutputFileName = name;
    }
    
    /**
     * Prepare for the results to be received.
     *
     * @param rp the ResultProducer that will generate the results
     * @throws Exception if an error occurs during preprocessing.
     */
    public void preProcess(ResultProducer rp) throws Exception {
  
      m_RP = rp;
      if ((m_OutputFile == null) || (m_OutputFile.getName().equals("-"))) {
        m_Out = new PrintWriter(System.out, true);
      } else {
        m_Out = new PrintWriter(
  	      new BufferedOutputStream(
  	      new FileOutputStream(m_OutputFile)), true);
      }
      printResultNames(m_RP);
    }
    
    /**
     * Perform any postprocessing. When this method is called, it indicates
     * that no more results will be sent that need to be grouped together
     * in any way.
     *
     * @param rp the ResultProducer that generated the results
     * @throws Exception if an error occurs
     */
    public void postProcess(ResultProducer rp) throws Exception {
      
      if (!(m_OutputFile == null) && !(m_OutputFile.getName().equals("-"))) {
        m_Out.close();
      }
    }
  
    /**
     * Determines if there are any constraints (imposed by the
     * destination) on the result columns to be produced by
     * resultProducers. Null should be returned if there are NO
     * constraints, otherwise a list of column names should be
     * returned as an array of Strings.
     * @param rp the ResultProducer to which the constraints will apply
     * @return an array of column names to which resutltProducer's
     * results will be restricted.
     * @throws Exception if an error occurs.
     */
    public String [] determineColumnConstraints(ResultProducer rp) throws Exception {
      return null;
    }
  
    /**
     * Just prints out each result as it is received.
     *
     * @param rp the ResultProducer that generated the result
     * @param key The key for the results.
     * @param result The actual results.
     * @throws Exception if the result could not be accepted.
     */
    public void acceptResult(ResultProducer rp, Object[] key, Object[] result) 
      throws Exception {
  
      if (m_RP != rp) {
        throw new Error("Unrecognized ResultProducer sending results!!");
      }
      for (int i = 0; i < key.length; i++) {
        if (i != 0) {
  	m_Out.print(',');
        }
        if (key[i] == null) {
  	m_Out.print("?");
        } else {
  	m_Out.print(Utils.quote(key[i].toString()));
        }
      }
      for (int i = 0; i < result.length; i++) {
        m_Out.print(',');
        if (result[i] == null) {
  	m_Out.print("?");
        } else {
  	m_Out.print(Utils.quote(result[i].toString()));
        }
      }
      m_Out.println("");
    }
  
    /**
     * Always says a result is required. If this is the first call,
     * prints out the header for the csv output.
     *
     * @param rp the ResultProducer wanting to generate the result
     * @param key The key for which a result may be needed.
     * @return true if the result should be calculated.
     * @throws Exception if it could not be determined if the result 
     * is needed.
     */
    public boolean isResultRequired(ResultProducer rp, Object[] key) 
      throws Exception {
  
      return true;
    }
  
  
    /**
     * Prints the names of each field out as the first row of the CSV output.
     *
     * @param rp the ResultProducer generating our results.
     * @throws Exception if the field names could not be determined.
     */
    private void printResultNames(ResultProducer rp) throws Exception {
  
      String [] key = rp.getKeyNames();
      for (int i = 0; i < key.length; i++) {
        if (i != 0) {
  	m_Out.print(',');
        }
        if (key[i] == null) {
  	m_Out.print("?");
        } else {
  	m_Out.print("Key_" + key[i].toString());
        }
      }
      String [] result = rp.getResultNames();
      for (int i = 0; i < result.length; i++) {
        m_Out.print(',');
        if (result[i] == null) {
  	m_Out.print("?");
        } else {
  	m_Out.print(result[i].toString());
        }
      }
      m_Out.println("");
    }
    
    /**
     * Returns the revision string.
     * 
     * @return		the revision
     */
    public String getRevision() {
      return RevisionUtils.extract("$Revision: 1.13 $");
    }
  } // CSVResultListener
  