SelectionMapper.java

/*
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU General Public License, version 2 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/gpl-2.0.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * 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.
 *
 *
 * Copyright 2005 - 2008 Pentaho Corporation.  All rights reserved. 
 * 
 * @created Oct 15, 2005 
 * @author dmoran
 */

package org.pentaho.platform.engine.services.runtime;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.pentaho.commons.connection.IPentahoMetaData;
import org.pentaho.commons.connection.IPentahoResultSet;
import org.pentaho.platform.api.engine.IActionParameter;
import org.pentaho.platform.api.engine.ISelectionMapper;

public class SelectionMapper implements ISelectionMapper {

  /**
   * Creates a SelectionMapper based on an IPentahoResultSet. If the result
   * set has 1 column, the values and display names will come from that
   * column. If it has more than 1 column, the first column will be used for
   * the values and the second will be used for the display names
   * 
   * @param resultSet
   *            The result set to get the data from
   * @param displayName
   *            The name used to describe the choice for this selection.
   *            Usually used as a header
   * @return SelectionMapper if successful or null
   */
  public static SelectionMapper create(final IPentahoResultSet resultSet, final String displayName,
      final String displayStyle) {
    return (SelectionMapper.create(resultSet, 1, -1, displayName, displayStyle));
  }

  /**
   * Creates a SelectionMapper based on an IPentahoResultSet. The columns to
   * use for the values and display names are passed in as column names.
   * 
   * @param resultSet
   *            The result set to get the data from
   * @param valueColName
   *            The name of the column to use for the values. If null, the
   *            first column will be used
   * @param dispColName
   *            The name of the column to use for the display names. If null,
   *            the values column will be used
   * @param displayName
   *            The name used to describe the choice for this selection.
   *            Usually used as a header
   * @return SelectionMapper if successful or null
   */
  public static SelectionMapper create(final IPentahoResultSet resultSet, final String valueColName,
      final String dispColName, final String displayName, final String displayStyle) {
    if (resultSet == null) {
      return (null);
    }

    IPentahoMetaData metaData = resultSet.getMetaData();
    if ((metaData == null) || (metaData.getColumnCount() < 1)) {
      // TODO surface an error
      return (null);
    }

    int valueColumnNo = (valueColName == null) ? 0 : metaData.getColumnIndex(valueColName);
    if (valueColumnNo < 0) {
      // TODO surface an error
      return (null);
    }

    int dispColumnNo = -1;
    if (dispColName != null) {
      dispColumnNo = metaData.getColumnIndex(dispColName);
      if (dispColumnNo < 0) {
        // TODO surface an error
        return (null);
      }
    }

    return (SelectionMapper.create(resultSet, ++valueColumnNo, ++dispColumnNo, displayName, displayStyle));
  }

  /**
   * Creates a SelectionMapper based on an IPentahoResultSet. The index of the
   * column to use for the values and display names are passed in. The index
   * is 1 based so the first (left most) column is 1.
   * 
   * @param resultSet
   *            The result set to get the data from
   * @param valueColName
   *            The index of the column to use for the values.
   * @param dispColName
   *            The index of the column to use for the display names. If 0
   *            then the valueColumn will be used.
   * @param displayName
   *            The name used to describe the choice for this selection.
   *            Usually used as a header
   * @return SelectionMapper if successful or null
   */
  public static SelectionMapper create(final IPentahoResultSet resultSet, int valueColIndex, int dispColIndex,
      final String displayName, final String displayStyle) {
    --valueColIndex;
    --dispColIndex;

    if ((resultSet == null) || (valueColIndex < 0)) {
      return (null);
    }

    IPentahoMetaData metaData = resultSet.getMetaData();
    if ((metaData == null) || (metaData.getColumnCount() < valueColIndex) || (metaData.getColumnCount() < dispColIndex)) {
      return (null);
    }

    ArrayList<Object> values = new ArrayList<Object>();

    HashMap<Object,Object> displayNames = (dispColIndex < 0) ? null : new HashMap<Object,Object>();
    Object row[] = resultSet.next();
    Object value, name;
    while (row != null) {
      value = row[valueColIndex];
      if (value != null) {
        value = value.toString();
        values.add(value);
        if (displayNames != null) {
          name = row[dispColIndex];
          displayNames.put(value, (name != null) ? name.toString() : value);
        }
      }
      row = resultSet.next();
    }
    // close the result set so we can loop through it again later if we need to
    resultSet.close();

    return (new SelectionMapper(values, displayNames, displayName, displayStyle));
  }

  /**
   * Creates a SelectionMapper based on an IActionParameter. The columns to
   * use for the values and display names are passed in as column names.
   * 
   * @param actionParam
   *            The ActionParameter to get the data from
   * @param valueColName
   *            The name of the column to use for the values. If null, the
   *            first column will be used
   * @param dispColName
   *            The name of the column to use for the display names. If null,
   *            the values column will be used
   * @param displayName
   *            The name used to describe the choice for this selection.
   *            Usually used as a header
   * @return SelectionMapper if successful or null
   */
  public static SelectionMapper create(final IActionParameter actionParam, final String valueColName,
      final String dispColName, final String displayName, final String displayStyle) {
    if (actionParam == null) {
      return (null);
    }

    Object value = actionParam.getValue();
    if (value instanceof IPentahoResultSet) {
      return (SelectionMapper.create((IPentahoResultSet) value, valueColName, dispColName, displayName, displayStyle));
    } else if ("property-map-list".equals(actionParam.getType())) { //$NON-NLS-1$
      return (SelectionMapper.createFromPropMapList((List) value, valueColName, dispColName, displayName, displayStyle));
    } else if (value instanceof List) {
      return (new SelectionMapper((List) value, null, displayName, displayStyle));
    }

    return (null);
  }

  /**
   * Creates a SelectionMapper based on a pentaho property map list. The index
   * of the column to use for the values and display names are passed in. The
   * index is 1 based so the first (left most) column is 1.
   * 
   * @param resultSet
   *            The result set to get the data from
   * @param valueColName
   *            The index of the column to use for the values.
   * @param dispColName
   *            The index of the column to use for the display names. If 0
   *            then the valueColumn will be used.
   * @param displayName
   *            The name used to describe the choice for this selection.
   *            Usually used as a header
   * @return SelectionMapper if successful or null
   */
  public static SelectionMapper createFromPropMapList(final List aList, final String valueColName,
      final String dispColName, final String displayName, final String displayStyle) {
    if (aList == null) {
      return (null);
    }

    ArrayList<String> selValues = new ArrayList<String>();
    HashMap<String,String> dispMap = new HashMap<String,String>();
    String val, disp;
    for (Iterator it = aList.iterator(); it.hasNext();) {
      try {
        Map hm = (Map) it.next();
        val = hm.get(valueColName).toString();
        if (val != null) {
          selValues.add(val);
        }
        disp = hm.get(dispColName).toString();
        if (disp != null) {
          dispMap.put(val, disp);
        }
      } catch (Exception ignore) {
      }
    }

    return (new SelectionMapper(selValues, dispMap, displayName, displayStyle));
  }

  Map selNames;

  List selValues;

  String displayName, displayStyle;

  private SelectionMapper(final List selValues, final Map selNames, final String displayName, final String displayStyle) {
    this.displayName = (displayName != null) ? displayName : ""; //$NON-NLS-1$
    this.selNames = selNames;
    this.selValues = (selValues != null) ? selValues : new ArrayList();
    this.displayStyle = displayStyle;
  }

  public String getDisplayStyle() {
    return displayStyle;
  }

  public String getSelectionDisplayName() {
    return (displayName);
  }

  public String getSelectionNameForValue(final String val) {
    Object rtn = null;
    if (selNames != null) {
      rtn = selNames.get(val);
    }
    return ((rtn == null) ? val : rtn.toString());
  }

  public List getSelectionValues() {
    return (selValues);
  }

  public Map getSelectionNameMap() {
    return (selNames);
  }

  public boolean hasValue(final String value) {
    return (selValues.contains(value));
  }

  public int selectionCount() {
    return (selValues.size());
  }

  public String getValueAt(final int index) {
    return (selValues.get(index).toString());
  }

  @Override
  public String toString() {
    StringBuffer sb = new StringBuffer("Display Name: ").append(getSelectionDisplayName()).append(" ["); //$NON-NLS-1$ //$NON-NLS-2$
    for (Iterator it = selValues.iterator(); it.hasNext();) {
      String value = it.next().toString();
      sb.append(" [").append(value).append(" : ").append(getSelectionNameForValue(value)).append("] "); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$  
    }
    sb.append("]"); //$NON-NLS-1$
    return (sb.toString());
  }

}