LocalizedInfo

/*
 * Copyright 2007-2011 smartics, Kronseder & Reiner GmbH
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package de.smartics.exceptions.i18n.message;

import java.io.Serializable;
import java.util.Locale;
import java.util.MissingResourceException;

import de.smartics.exceptions.core.Code;
import de.smartics.exceptions.i18n.I18nExceptionContext;
import de.smartics.exceptions.i18n.I18nExceptionContextManager;

/**
 * Controls the localized information for a throwable.
 *
 * @author <a href="mailto:robert.reiner@smartics.de">Robert Reiner</a>
 * @version $Revision:591 $
 */
public class LocalizedInfo implements Serializable
{
  // ********************************* Fields *********************************

  // --- constants ------------------------------------------------------------

  /**
   * The class version identifier.
   */
  private static final long serialVersionUID = 1L;

  /**
   * The suffix for the auto generated bundle name.
   * <p>
   * The value of this constant is {@value}.
   */
  public static final String BUNDLE_NAME_SUFFIX = "Bundle";

  /**
   * The localization key to fetch messages from message bundles. If this value
   * is not set, the {@link String} representation of the provided code instance
   * is used.
   *
   * @serial
   */
  protected final String resourceKey;

  /**
   * The fully qualified base name of the bundle to use.
   * <p>
   * This bundle base name must never be <code>null</code>.
   *
   * @serial
   */
  protected final String bundleBaseName;

  // --- members --------------------------------------------------------------

  // ****************************** Initializer *******************************

  // ****************************** Constructors ******************************

  /**
   * Default constructor.
   *
   * @param code the error or exception code of the exception.
   * @param bundleBaseName the fully qualified name of the bundle to use.
   * @param resourceKey the localization key to fetch messages from message
   *          bundles.
   */
  public LocalizedInfo(final Code code, final String bundleBaseName,
      final String resourceKey)
  {
    this.resourceKey = resourceKey != null ? resourceKey : code.getCode();
    this.bundleBaseName =
        bundleBaseName != null ? bundleBaseName : createDefaultBundleName(code);
  }

  // ****************************** Inner Classes *****************************

  // ********************************* Methods ********************************

  // --- init -----------------------------------------------------------------

  /**
   * Created the default bundle name for the given code if no bundle name is
   * provided. The name is build by using the class name of the code
   * implementation and the {@link LocalizedInfo#BUNDLE_NAME_SUFFIX}.
   *
   * @param code the code that provides the bundle name prefix.
   * @return the default bundle name derived from the code's class.
   */
  private String createDefaultBundleName(final Code code)
  {
    final String defaultBundleBaseName =
        code.getClass().getName() + BUNDLE_NAME_SUFFIX;
    return defaultBundleBaseName;
  }

  // --- get&set --------------------------------------------------------------

  /**
   * Returns the localization key to fetch messages from message bundles. If
   * this value is not set, the {@link String} representation of the code
   * instance is used.
   *
   * @return the localization key to fetch messages from message bundles.
   */
  public String getResourceKey()
  {
    return this.resourceKey;
  }

  /**
   * Returns the fully qualified base name of the bundle to use.
   *
   * @return the fully qualified base name of the bundle to use.
   */
  public String getBundleBaseName()
  {
    return this.bundleBaseName;
  }

  // --- business -------------------------------------------------------------

  /**
   * Returns the localized message for the given locale.
   *
   * @param throwable the throwable to construct the localized message.
   * @param locale the locale for which the message is requested.
   * @param loader the loader to read the message bundle.
   * @return returns the localized message of this exception.
   */
  public String getLocalizedMessage(final Throwable throwable,
      final Locale locale, final ClassLoader loader)
  {
    final I18nExceptionContext context =
        I18nExceptionContextManager.getInstance().getContext(loader);
    final MessageTemplate template = context.getMessageTemplateId();
    if (MessageTemplate.SINGLE_LINE_STANDARD == template)
    {
      return getLocalizedSingleLineMessage(throwable, locale, loader, true);
    }
    if (MessageTemplate.SINGLE_LINE_SUMMARY_ONLY == template)
    {
      return getLocalizedSingleLineMessage(throwable, locale, loader, false);
    }
    else // multi-line all
    {
      return getLocalizedTextMessage(throwable, locale, loader);
    }
  }

  /**
   * Returns the localized message for the given locale.
   *
   * @param throwable the throwable to construct the localized message.
   * @param locale the locale for which the message is requested.
   * @param loader the loader to read the message bundle.
   * @return returns the localized message of this exception.
   */
  public String getLocalizedSingleLineMessage(final Throwable throwable,
      final Locale locale, final ClassLoader loader, final boolean standard)
  {
    final SingleLineTextHandler handler =
        new SingleLineTextHandler(bundleBaseName, resourceKey, standard);
    return handler.getMessage(throwable, locale, loader);
  }

  /**
   * Returns the structured and localized message for the given locale,
   * returning each part of information that is provided.
   *
   * @param throwable the throwable to construct the localized message.
   * @param locale the locale for which the message is requested.
   * @param loader the loader to read the message bundle.
   * @return returns the localized message of this exception.
   */
  public String getLocalizedTextMessage(final Throwable throwable,
      final Locale locale, final ClassLoader loader)
  {
    final StructuredTextHandler handler =
        new StructuredTextHandler(bundleBaseName, resourceKey);
    return handler.getMessage(throwable, locale, loader);
  }

  /**
   * Returns the localized message for the given locale.
   *
   * @param throwable the throwable to construct the localized message.
   * @param keyPrefix the prefix of the key to load from the bundle.
   * @param locale the locale for which the message is requested.
   * @param messageType the type of message to localize.
   * @param loader the loader to read the message bundle.
   * @return returns the localized message of this exception.
   */
  public String getLocalizedMessage(final Throwable throwable,
      final String keyPrefix, final Locale locale,
      final MessageType messageType, final ClassLoader loader)
  {
    final SingleLineTextHandler handler =
        new SingleLineTextHandler(bundleBaseName, resourceKey, true);
    try
    {
      return handler.fetchLocalizedMessage(throwable, keyPrefix, locale,
          messageType, loader);
    }
    catch (final MissingResourceException e)
    {
      return keyPrefix + '.' + messageType;
    }
  }

  // --- object basics --------------------------------------------------------

}