instancequery.java

Java 编写的多种数据挖掘算法 包括聚类、分类、预处理等

/*
 *    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.
 */

/*
 *    InstanceQuery.java
 *    Copyright (C) 1999 Len Trigg
 *
 */

package weka.experiment;

import weka.core.Attribute;
import weka.core.FastVector;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Option;
import weka.core.OptionHandler;
import weka.core.SparseInstance;
import weka.core.Utils;

import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.util.Date;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;

/**
 * Convert the results of a database query into instances. The jdbc
 * driver and database to be used default to "jdbc.idbDriver" and
 * "jdbc:idb=experiments.prp". These may be changed by creating
 * a java properties file called DatabaseUtils.props in user.home or
 * the current directory. eg:<p>
 *
 * <code><pre>
 * jdbcDriver=jdbc.idbDriver
 * jdbcURL=jdbc:idb=experiments.prp
 * </pre></code><p>
 *
 * Command line use just outputs the instances to System.out. <p/>
 *
 <!-- options-start -->
 * Valid options are: <p/>
 * 
 * <pre> -Q &lt;query&gt;
 *  SQL query to execute.</pre>
 * 
 * <pre> -S
 *  Return sparse rather than normal instances.</pre>
 * 
 * <pre> -U &lt;username&gt;
 *  The username to use for connecting.</pre>
 * 
 * <pre> -P &lt;password&gt;
 *  The password to use for connecting.</pre>
 * 
 * <pre> -D
 *  Enables debug output.</pre>
 * 
 <!-- options-end -->
 *
 * @author Len Trigg ([e-mail])
 * @version $Revision: 1.18 $
 */
public class InstanceQuery 
  extends DatabaseUtils 
  implements OptionHandler {
  
  /** for serialization */
  static final long serialVersionUID = 718158370917782584L;

  /** Determines whether sparse data is created */
  boolean m_CreateSparseData = false;
  
  /** Query to execute */
  String m_Query = "SELECT * from ?";

  /**
   * Sets up the database drivers
   *
   * @throws Exception if an error occurs
   */
  public InstanceQuery() throws Exception {

    super();
  }

  /**
   * Returns an enumeration describing the available options <p>
   *
   * @return an enumeration of all options
   */
   public Enumeration listOptions () {
     Vector result = new Vector();

     result.addElement(
         new Option("\tSQL query to execute.",
                    "Q",1,"-Q <query>"));
     
     result.addElement(
         new Option("\tReturn sparse rather than normal instances.", 
                    "S", 0, "-S"));
     
     result.addElement(
         new Option("\tThe username to use for connecting.", 
                    "U", 1, "-U <username>"));
     
     result.addElement(
         new Option("\tThe password to use for connecting.", 
                    "P", 1, "-P <password>"));
     
     result.addElement(
         new Option("\tEnables debug output.", 
                    "D", 0, "-D"));
     
     return result.elements();
   }

  /**
   * Parses a given list of options.
   *
   <!-- options-start -->
   * Valid options are: <p/>
   * 
   * <pre> -Q &lt;query&gt;
   *  SQL query to execute.</pre>
   * 
   * <pre> -S
   *  Return sparse rather than normal instances.</pre>
   * 
   * <pre> -U &lt;username&gt;
   *  The username to use for connecting.</pre>
   * 
   * <pre> -P &lt;password&gt;
   *  The password to use for connecting.</pre>
   * 
   * <pre> -D
   *  Enables debug output.</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      tmpStr;
    
    setSparseData(Utils.getFlag('S',options));

    tmpStr = Utils.getOption('Q',options);
    if (tmpStr.length() != 0)
      setQuery(tmpStr);

    tmpStr = Utils.getOption('U',options);
    if (tmpStr.length() != 0)
      setUsername(tmpStr);

    tmpStr = Utils.getOption('P',options);
    if (tmpStr.length() != 0)
      setPassword(tmpStr);

    setDebug(Utils.getFlag('D',options));
  }

  /**
   * Returns the tip text for this property
   * @return tip text for this property suitable for
   * displaying in the explorer/experimenter gui
   */
  public String queryTipText() {
    return "The SQL query to execute against the database.";
  }
  
  /**
   * Set the query to execute against the database
   * @param q the query to execute
   */
  public void setQuery(String q) {
    m_Query = q;
  }

  /**
   * Get the query to execute against the database
   * @return the query
   */
  public String getQuery() {
    return m_Query;
  }

  /**
   * Returns the tip text for this property
   * @return tip text for this property suitable for
   * displaying in the explorer/experimenter gui
   */
  public String sparseDataTipText() {
    return "Encode data as sparse instances.";
  }

  /**
   * Sets whether data should be encoded as sparse instances
   * @param s true if data should be encoded as a set of sparse instances
   */
  public void setSparseData(boolean s) {
    m_CreateSparseData = s;
  }

  /**
   * Gets whether data is to be returned as a set of sparse instances
   * @return true if data is to be encoded as sparse instances
   */
  public boolean getSparseData() {
    return m_CreateSparseData;
  }

  /**
   * Gets the current settings of InstanceQuery
   *
   * @return an array of strings suitable for passing to setOptions()
   */
  public String[] getOptions () {

    Vector options = new Vector();

    options.add("-Q"); 
    options.add(getQuery());
 
    if (getSparseData())
      options.add("-S");

    if (!getUsername().equals("")) {
      options.add("-U");
      options.add(getUsername());
    }

    if (!getPassword().equals("")) {
      options.add("-P");
      options.add(getPassword());
    }

    if (getDebug())
      options.add("-D");

    return (String[]) options.toArray(new String[options.size()]);
  }

  /**
   * Makes a database query using the query set through the -Q option 
   * to convert a table into a set of instances
   *
   * @return the instances contained in the result of the query
   * @throws Exception if an error occurs
   */
  public Instances retrieveInstances() throws Exception {
    return retrieveInstances(m_Query);
  }

  /**
   * Makes a database query to convert a table into a set of instances
   *
   * @param query the query to convert to instances
   * @return the instances contained in the result of the query, NULL if the
   *         SQL query doesn't return a ResultSet, e.g., DELETE/INSERT/UPDATE
   * @throws Exception if an error occurs
   */
  public Instances retrieveInstances(String query) throws Exception {

    if (m_Debug) 
      System.err.println("Executing query: " + query);
    connectToDatabase();
    if (execute(query) == false) {