vaadin-framework/src/com/itmill/toolkit/terminal/gwt/server/Log.java

/* *************************************************************************
 
 IT Mill Toolkit 

 Development of Browser User Interfaces Made Easy

 Copyright (C) 2000-2006 IT Mill Ltd
 
 *************************************************************************

 This product is distributed under commercial license that can be found
 from the product package on license.pdf. Use of this product might 
 require purchasing a commercial license from IT Mill Ltd. For guidelines 
 on usage, see licensing-guidelines.html

 *************************************************************************
 
 For more information, contact:
 
 IT Mill Ltd                           phone: +358 2 4802 7180
 Ruukinkatu 2-4                        fax:   +358 2 4802 7181
 20540, Turku                          email:  info@itmill.com
 Finland                               company www: www.itmill.com
 
 Primary source for information and releases: www.itmill.com

 ********************************************************************** */

package com.itmill.toolkit.terminal.gwt.server;

/**
 * <p>
 * Class providing centralized logging services. The logger defines five message
 * types, and provides methods to create messages of those types. These types
 * are:
 * </p>
 * 
 * <ul>
 * <li> <code>info</code> - Useful information generated during normal
 * operation of the application.
 * <li> <code>warning</code> - An error situation has occurred, but the
 * operation was able to finish succesfully.
 * <li> <code>error</code> - An error situation which prevented the operation
 * from finishing succesfully.
 * <li> <code>debug</code> - Internal information from the application meant
 * for developers.
 * <li> <code>exception</code> - A Java exception reported using the logger.
 * Includes the exception stack trace and a possible free-form message.
 * </ul>
 * 
 * <p>
 * Currently the class offers logging only to the standard output.
 * </p>
 * 
 * @author IT Mill Ltd.
 * @version
 * @VERSION@
 * @since 5.0
 */
class Log {

	private static boolean useStdOut = true;

	private static String LOG_MSG_INFO = "[INFO]";

	private static String LOG_MSG_ERROR = "[ERROR]";

	private static String LOG_MSG_WARN = "[WARNING]";

	private static String LOG_MSG_DEBUG = "[DEBUG]";

	private static String LOG_MSG_EXCEPT = "[EXCEPTION]";

	/**
	 * Logs the <code>warning</code> message.
	 * 
	 * @param message
	 *            the Message String to be logged.
	 */
	static synchronized void warn(java.lang.String message) {
		if (Log.useStdOut)
			System.out.println(LOG_MSG_WARN + " " + message);
	}

	/**
	 * Logs the <code>debug</code> message.
	 * 
	 * @param message
	 *            the Message String to be logged.
	 */
	static synchronized void debug(java.lang.String message) {
		if (Log.useStdOut)
			System.out.println(LOG_MSG_DEBUG + " " + message);
	}

	/**
	 * Logs an <code>info</code> message.
	 * 
	 * @param message
	 *            the Message String to be logged.
	 */
	static synchronized void info(java.lang.String message) {
		if (Log.useStdOut)
			System.out.println(LOG_MSG_INFO + " " + message);
	}

	/**
	 * Logs the Java exception and an accompanying error message.
	 * 
	 * @param message
	 *            the Message String to be logged.
	 * @param e
	 *            the Exception to be logged.
	 */
	static synchronized void except(java.lang.String message, Exception e) {
		if (Log.useStdOut) {
			System.out.println(LOG_MSG_EXCEPT + " " + message);
			e.printStackTrace();
		}
	}

	/**
	 * Logs the <code>error</code> message.
	 * 
	 * @param message
	 *            the Message String to be logged.
	 */
	static synchronized void error(java.lang.String message) {
		if (Log.useStdOut)
			System.out.println(LOG_MSG_ERROR + " " + message);
	}
}