mininginputstream.java

一个数据挖掘软件ALPHAMINERR的整个过程的JAVA版源代码

/*
 *    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.
 */

 /**
  * Title: XELOPES Data Mining Library
  * Description: The XELOPES library is an open platform-independent and data-source-independent library for Embedded Data Mining.
  * Copyright: Copyright (c) 2002 Prudential Systems Software GmbH
  * Company: ZSoft (www.zsoft.ru), Prudsys (www.prudsys.com)
  * @author Valentine Stepanenko ([e-mail])
  * @author Michael Thess
  * @version 1.1
  */

package com.prudsys.pdm.Input;

import java.util.Enumeration;

import com.prudsys.pdm.Core.MiningAttribute;
import com.prudsys.pdm.Core.MiningDataSpecification;
import com.prudsys.pdm.Core.MiningException;
import com.prudsys.pdm.Core.MiningMatrixElement;
import com.prudsys.pdm.Input.Records.Arff.MiningArffStream;
import com.prudsys.pdm.Input.Records.Csv.MiningCsvStream;
import com.prudsys.pdm.Input.Records.Transactions.TransactionStream;

/**
 * A table of vectors representing an input mining data, which is usually
 * generated by reading a file or by executing a statement that queries
 * a database. Each vector in this table is going to be a MiningVector or
 * one of its subclasses.<p>
 *
 * A <code>MiningInputStream</code> object maintains a cursor pointing to its
 * current vector. Initially the cursor is positioned before the first row.
 * The <code>next</code> method moves the cursor to the next row, and because it
 * returns false when there are no more rows in the <code>MiningInputStream</code>
 * object, it can be used in a while loop to iterate through the data.
 * Use <code>read()</code> method to retrieve vector from the current cursor
 * position. Depending on the input mining source's nature we will recognize a
 * few <code>MiningInputStream</code> types: forward only (default), resetable
 * and navigatable.<p>
 *
 * A default <code>MiningInputStream</code> object has a cursor that moves
 * forward only. Thus, it is possible to iterate through it only once and
 * only from the first row to the last row.
 * Resetable <code>MiningInputStream</code> allows to position cursor back to
 * the first vector and repeat data reading.
 * Navigatable <code>MiningInputStream</code> allows to position cursor to
 * any vector in the table.<p>
 *
 * In Version 1.1 an update mechanism for mining input streams was added.
 * Updateble input streams allow to edit the existing input stream. All
 * updateble methods start with 'update'.
 *
 * The meta data of a <code>MiningInputStream</code> is returned by the
 * <code>getMetaData</code> method.<p>
 */
public abstract class MiningInputStream extends com.prudsys.pdm.Cwm.Core.Class implements MiningMatrixElement
{
    // -----------------------------------------------------------------------
    //  Variables declarations
    // -----------------------------------------------------------------------
	   
  	//<<Frank J. Xu, 30/03/2005
    //Add function to update the type of categorical data. 
	public static final int CATEGORICAL_ATTRIBUTE_BOUND = 50;    	
	//>>Frank J. Xu, 30/03/2005
	
    /** Meta data with attributes description. Logical data model. */
    protected MiningDataSpecification metaData;

    /** Physical data model. */
    protected org.omg.cwm.objectmodel.core.Package physicalModel;

    /** Current cursor position. */
    protected int cursorPosition = -1;

    /** MiningVector located on the current cursor position. */
    protected MiningVector cursorVector;

    /** True, if MiningInputStream contains missing values. */
    protected boolean missingValues;

    // -----------------------------------------------------------------------
    //  Constructor
    // -----------------------------------------------------------------------
    /**
     * MiningInputStream constructor.
     */
    public MiningInputStream()
    {
    }

    // -----------------------------------------------------------------------
    //  Getter and setter methods
    // -----------------------------------------------------------------------
    /**
     * Returns the meta data.
     *
     * @return the meta data
     * @exception MiningException coul not retrieve meta data
     */
    public MiningDataSpecification getMetaData() throws MiningException
    {
        return metaData;
    }

    /**
     * Returns the logical model of the Data Mining source. Of course,
     * this is the meta data itself.
     *
     * @return logical model in terms of CWM
     */
    public org.omg.cwm.objectmodel.core.Classifier getLogicalModel()
    {
       return metaData;
    }

    /**
     * The MiningInputStream's metaData is the logical model of the Data Mining
     * source. Of course, the data also has a physical representation.  It is
     * stored in memory, files, databases, etc. The physical representation
     * is modeled through extended mining input streams like MiningArrayStream,
     * MiningSqlStream, etc. This method delivers this physical model in
     * terms of CWM. <p>
     *
     * The method returns the physical model on the CWM Package level,
     * i.e. for databases it delivers the catalog, for files the record file,
     * for multidimensional data the schema, etc. Notice that the logical model
     * (metaData) is just from the CWM Classifier level. Package level of the
     * physical model is required since the data of the logical model may
     * be distributed over some Classifier-like structures like tables in
     * databases. <p>
     *
     * Use the method findPhysicalModel to determine the physical model before
     * calling this one. <p>
     *
     * The mapping between the logical model (metaData) and the
     * physical model (delivered by this method) is obtained by the
     * method getPhysicalToLogicalModelTransformation.
     *
     * @return physical model in terms of CWM
     * @exception MiningException couldn't access phsyical model
     */
    public org.omg.cwm.objectmodel.core.Package getPhysicalModel()
    {
      return physicalModel;
    }

    /**
     * Determines physical model and assigns it to variable physicalModel.
     * Use getPhysicalModel to retrieve the model.
     *
     * @throws MiningException error while determening physical model
     */
    public abstract void findPhysicalModel() throws MiningException;

    /**
     * Returns the CWM mapping from the physical to the logical data model.
     *
     * @return transformation of physical to logical data model
     * @throws MiningException couldn't get transformation
     */
    public abstract org.omg.cwm.analysis.transformation.TransformationMap getPhysicalToLogicalModelTransformation()
        throws MiningException;

    /**
     * Returns the supported stream access methods of a mining input stream
     * implemenation. They are from the following list: "recognize", "reset",
     * "move", "updateSetMetaData", "updateRemoveAllVectors",
     * "updateSetMetaData". This allows a consumer method of the stream
     * dynamically to apply the supported methods. Notice that every stream
     * must actively support the methods "next" and "read"; therefore
     * they are not included in this list.
     *
     * @return list of supported stream methods
     */
    public abstract Enumeration getSupportedStreamMethods();

    /**
     * Return the current cursor position.
     *
     * @return     the current cursor position.
     */
    public int getCursorPosition()
    {
        return cursorPosition;
    }

    /**
     * Determines the number of vectors. <p>
     *
     * In this most simple implementation, it utilizes the
     * reset and next methods. The cursor position is stored
     * into a temporary variable and finally recovered. <p>
     *
     * Most implementations of MiningInputStream will
     * overwrite this method.
     *
     * @return number of vectors
     * @exception MiningException method reset not implemented
     */
    public int getVectorsNumber() throws MiningException
    {
        int currCursorPosition = cursorPosition;
        // Count vectors:
        reset();
        int numbVec = 0;
        while (next())
          numbVec = numbVec + 1;
        // Restore cursor position;
        reset();
        for (int i = 0; i < currCursorPosition; i++)
          next();
        return numbVec;
    }

    /**
     * Return true if there are missing values.
     *
     * @return true if there are missing values
     */
    public boolean isMissingValues()
    {
        return missingValues;
    }

    // -----------------------------------------------------------------------
    //  General stream methods
    // -----------------------------------------------------------------------
    /**
     * Open mining data stream.
     *
     * @exception MiningException if a mining source access error occurs
     */
    public abstract void open() throws MiningException;

    /**
     * Close mining data stream.
     *
     * @exception MiningException if a mining source access error occurs
     */
    public abstract void close() throws MiningException;

    /**
     * Recognize the input stream's meta data by analyzing the input stream.
     *
     * @return     the MiningDataSpecification
     * @exception  MiningException  if an error occurs
     */
    public abstract MiningDataSpecification recognize() throws MiningException;

    // -----------------------------------------------------------------------
    //  Methods of cursor positioning
    // -----------------------------------------------------------------------
    /**
     * Resets the cursor from its current position to position before
     * the first row. Some mininig sources doesn't support reseting.
     *
     * @exception MiningException if a mining source access error occurs
     */
    public abstract void reset() throws MiningException;

    /**
     * Moves the cursor down one row from its current position.
     * A <code>MiningInputStream</code> cursor is initially positioned
     * before the first row; the first call to the method
     * <code>next</code> makes the first row the current row; the
     * second call makes the second row the current row, and so on.
     *
     * @return <code>true</code> if the new current row is valid;
     * <code>false</code> if there are no more rows
     * @exception MiningException if a mining source access error occurs
     */
    public abstract boolean next() throws MiningException;

    /**
     * Moves the cursor to the given row number in
     * this <code>MiningInputStream</code> object.
     *
     * <p>If the row number is positive, the cursor moves to
     * the given row number with respect to the beginning of the
     * mining input stream.  The first row is row 1, the second
     * is row 2, and so on.
     *
     * <p>If the given row number is negative, the cursor moves to
     * an absolute row position with respect to the end of the
     * mining input stream.
     *
     * <p>An attempt to position the cursor beyond the first/last row in
     * the mining input stream leaves the cursor before the first row or
     * after the last row.
     *
     * @param position new cursor position
     * @return <code>true</code> if the cursor is on the mining input stream;
     * <code>false</code> otherwise
     * @exception MiningException if a mining source access error
     * occurs, the row is <code>0</code>, or the MiningInputStream type is
     * <code>TYPE_FORWARD_ONLY</code>
     */
    public abstract boolean move( int position ) throws MiningException;

    // -----------------------------------------------------------------------
    //  Methods of reading from the stream
    // -----------------------------------------------------------------------
    /**
     * Reads the MiningVector on the current cursor position from the
     * input stream.
     *
     * <p> A subclass must provide an implementation of this method.
     *
     * @return     the MiningVector
     * @exception  MiningException  if an error occurs
     */