Application: gvSIG desktop » Library: org.gvsig.tools

import org.gvsig.tools.dataTypes.AbstractCoercion;

import org.gvsig.tools.dataTypes.DataTypeUtils;

import org.gvsig.tools.dataTypes.DataTypesManager;

import org.gvsig.tools.dataTypes.CoercionContext;

import org.gvsig.tools.dataTypes.CoercionContextLocale;

public abstract class AbstractCoerceToDate extends AbstractCoercion {

  @Override

  public Object coerce(Object value) throws CoercionException {

    return coerce(value, DataTypeUtils.coerceContextDefaultLocale());

  }

  @Override

  public Object coerce(Object value, CoercionContext context) throws CoercionException {

    Locale locale;

    if (context instanceof CoercionContextLocale) {

      locale = ((CoercionContextLocale) context).locale();

    } else {

      locale = Locale.getDefault();

    return coerce(value, this.getFormatters(locale));

  }

  protected Object coerce(Object value, DateFormat[] formatters) throws CoercionException {

    if (value instanceof Number) {

      return new Date(((Number)value).longValue());

    @SuppressWarnings("null")

    String valueStr = value.toString();

    if (valueStr == null) {

      return null;

    }

    valueStr = valueStr.trim();

    if (valueStr.length() == 0) {

      return null;

    }

    if (valueStr.toLowerCase().equals("now")) {

      return this.now();

    }

    try {

      Date d = this.valueOf(valueStr);

      if (d != null) {

        return d;

      }

    } catch (Exception ex) {

      // Continue

    }

    for (DateFormat formatter : formatters) {

      try {

        Date d = formatter.parse(valueStr);

        if (d != null) {

          return d;

      } catch (ParseException e) {

        // Continue

      }

    throw new CoercionException(getErrorMessage(formatters, valueStr));

  }

  private String getErrorMessage(DateFormat[] formatters, String value) throws CoercionException {

    StringBuilder builder = new StringBuilder();

    builder.append("The value to coerce (\"");

    builder.append(value);

    builder.append("\") has an invalid ");

    builder.append(getDateType());

    builder.append(" String format. The expected one is:");

    for (DateFormat formatter : formatters) {

      String formatDesc = formatter instanceof SimpleDateFormat

              ? ((SimpleDateFormat) formatter).toLocalizedPattern()

              : formatter.toString();

      builder.append(" '");

      builder.append(formatDesc);

      builder.append("'");

    return builder.toString();

  }

  /**

   * Returns the {@link DateFormat} to apply when the value to coerce is not of

   * Date type and it will be parsed as String.

   *

   * @param locale

   * @return the {@link DateFormat} to apply to parse the value to coerce as

   * {@link String}

   */

  protected abstract DateFormat[] getFormatters(Locale locale);

  protected Date now() {

    Date d = new Date();

    return d;

  }

  protected Date valueOf(String value) {

    return null;

  }

  /**

   * Returns the name of the Date type being coerced. Ex: Date, DateTime, Time.

   * Only used for description when an error is produced when coercing the

   * value.

   *

   * @return the name of the Date type being coerced

   */

  protected abstract String getDateType();