BigDecimalPoemType.java

/*
 * $Source$
 * $Revision$
 *
 * Copyright (C) 2003 Samuel Goldstein
 *
 * Part of Melati (http://melati.org), a framework for the rapid
 * development of clean, maintainable web applications.
 *
 * Melati is free software; Permission is granted to copy, distribute
 * and/or modify this software under the terms either:
 *
 * a) 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,
 *
 *    or
 *
 * b) any version of the Melati Software License, as published
 *    at http://melati.org
 *
 * You should have received a copy of the GNU General Public License and
 * the Melati Software License along with this program;
 * if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the
 * GNU General Public License and visit http://melati.org to obtain the
 * Melati Software License.
 *
 * Feel free to contact the Developers of Melati (http://melati.org),
 * if you would like to work out a different arrangement than the options
 * outlined here.  It is our intention to allow Melati to be used by as
 * wide an audience as possible.
 *
 * 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.
 *
 * Contact details for copyright holder:
 *
 *     Samuel Goldstein <samuel At 1969.ws>
 *     http://www.1969.ws
 *     13101 W. Washington Blvd Suite 248, Los Angeles, CA 90066 USA
 */

package org.melati.poem;

import java.sql.Types;
import java.sql.ResultSet;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.math.BigDecimal;
import org.melati.poem.dbms.Dbms;

/**
 * Java "BigDecimal", dependant upon the database/SQL implementation.
 *
 * By default, this is a 22 digit number, with 2 digits after the
 * decimal.
 * */
public class BigDecimalPoemType extends FixedPointAtomPoemType<BigDecimal> {

  /**
   * Constructor.
   * 
   * @param nullable whether nullable 
   */
  public BigDecimalPoemType(boolean nullable) {
    super(Types.DECIMAL, "DECIMAL", nullable, 22, 2);
  }

  /**
   * Constructor.
   * 
   * @param nullable whether nullable 
   * @param precision defaults to 22
   * @param scale defaults to 2
   */
  public BigDecimalPoemType(boolean nullable, int precision, int scale) {
    super(Types.DECIMAL, "DECIMAL", nullable, precision, scale);
    // because a newly added column of this type won't have valid 
    // numbers, we fix that here...
    // This does not appear to be needed - timp 01/01/2006
    /* 
    if (precision <= 0) {
      setPrecision(22);
    }
    if (scale < 0) {
      setScale(2);
    }
    */
  }

  protected void _assertValidRaw(Object raw) {
    if (raw != null && !(raw instanceof BigDecimal))
      throw new TypeMismatchPoemException(raw, this);
  }

  protected BigDecimal _getRaw(ResultSet rs, int col) throws SQLException {
    synchronized (rs) {
      BigDecimal x = rs.getBigDecimal(col);
      return rs.wasNull() ? null : x; }
  }

  protected void _setRaw(PreparedStatement ps, int col, Object real)
    throws SQLException {
    ps.setBigDecimal(col, ((BigDecimal)real));
  }

  protected BigDecimal _rawOfString(String rawString) throws ParsingPoemException {
    try {
      return new BigDecimal(rawString);
    } catch (NumberFormatException e) {
      throw new ParsingPoemException(this, rawString, e);
    }
  }

  protected String _sqlDefinition(Dbms dbms) {
    try {
      return dbms.getFixedPtSqlDefinition(getScale(), getPrecision());
    } catch (SQLException e) {
      throw new SQLSeriousPoemException(e);
    }
  }

  /**
   * Whilst BigDecimal cannot represent all Doubles it can represent 
   * legacy money doubles, so we allow it to enable upgrades from Doubles 
   * to BigDecimals.
   * @see org.melati.poem.BasePoemType#_canRepresent(org.melati.poem.SQLPoemType)
   */
  protected boolean _canRepresent(SQLPoemType<?> other) {
    return // sqlTypeCode() == other.sqlTypeCode() && //commented out to allow doubles  
           other instanceof BigDecimalPoemType || other instanceof DoublePoemType;
  }

  /**
   * @return the field type used in the Data Structure Definition language.
   */
  public String toDsdType() {
    return "BigDecimal";
  }

  protected void _saveColumnInfo(ColumnInfo columnInfo)
    throws AccessPoemException {
    columnInfo.setTypefactory(PoemTypeFactory.BIGDECIMAL);
    columnInfo.setPrecision(getPrecision());
    columnInfo.setScale(getScale());
  }

}