Messages.java

/*
 Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
 

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FLOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  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; version 2
  of the License.

  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., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA



 */
package com.mysql.jdbc;

import java.text.MessageFormat;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * Support for localized messages.
 * 
 * @author Mark Matthews
 * @version $Id$
 */
public class Messages {

	private static final String BUNDLE_NAME = "com.mysql.jdbc.LocalizedErrorMessages"; //$NON-NLS-1$

	private static final ResourceBundle RESOURCE_BUNDLE;

	static {
		ResourceBundle temp = null;

		//
		// Overly-pedantic here, some appserver and JVM combos don't deal
		// well with the no-args version, others don't deal well with
		// the three-arg version, so we need to try both :(
		//

		try {
			temp = ResourceBundle.getBundle(BUNDLE_NAME, Locale.getDefault(),
					Messages.class.getClassLoader());
		} catch (Throwable t) {
			try {
				temp = ResourceBundle.getBundle(BUNDLE_NAME);
			} catch (Throwable t2) {
				RuntimeException rt = new RuntimeException(
						"Can't load resource bundle due to underlying exception "
								+ t.toString());
				rt.initCause(t2);
				
				throw rt;
			}
		} finally {
			RESOURCE_BUNDLE = temp;
		}
	}

	/**
	 * Returns the localized message for the given message key
	 * 
	 * @param key
	 *            the message key
	 * @return The localized message for the key
	 */
	public static String getString(String key) {
		if (RESOURCE_BUNDLE == null) {
			throw new RuntimeException(
					"Localized messages from resource bundle '" + BUNDLE_NAME
							+ "' not loaded during initialization of driver.");
		}

		try {
			if (key == null) {
				throw new IllegalArgumentException(
						"Message key can not be null");
			}

			String message = RESOURCE_BUNDLE.getString(key);

			if (message == null) {
				message = "Missing error message for key '" + key + "'";
			}

			return message;
		} catch (MissingResourceException e) {
			return '!' + key + '!';
		}
	}

	public static String getString(String key, Object[] args) {
		return MessageFormat.format(getString(key), args);
	}

	/**
	 * Dis-allow construction ...
	 */
	private Messages() {

		// XXX Auto-generated constructor stub
	}
}