consolehandler.java

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/*
 * @(#)ConsoleHandler.java	1.9 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */


package java.util.logging;

import java.io.*;
import java.net.*;

/**
 * This <tt>Handler</tt> publishes log records to <tt>System.err</tt>.
 * By default the <tt>SimpleFormatter</tt> is used to generate brief summaries.
 * <p>
 * <b>Configuration:</b>
 * By default each <tt>ConsoleHandler</tt> is initialized using the following
 * <tt>LogManager</tt> configuration properties.  If properties are not defined
 * (or have invalid values) then the specified default values are used.
 * <ul>
 * <li>   java.util.logging.ConsoleHandler.level 
 *	  specifies the default level for the <tt>Handler</tt>
 *	  (defaults to <tt>Level.INFO</tt>).
 * <li>   java.util.logging.ConsoleHandler.filter
 *	  specifies the name of a <tt>Filter</tt> class to use
 *	  (defaults to no <tt>Filter</tt>).
 * <li>   java.util.logging.ConsoleHandler.formatter
 * 	  specifies the name of a <tt>Formatter</tt> class to use
 *  	  (defaults to <tt>java.util.logging.SimpleFormatter</tt>).
 * <li>   java.util.logging.ConsoleHandler.encoding 
 *	  the name of the character set encoding to use (defaults to
 *	  the default platform encoding).
 * </ul>
 * <p>
 * @version 1.9, 01/23/03
 * @since 1.4
 */

public class ConsoleHandler extends StreamHandler {
    // Private method to configure a ConsoleHandler from LogManager
    // properties and/or default values as specified in the class
    // javadoc.
    private void configure() {
        LogManager manager = LogManager.getLogManager();
	String cname = ConsoleHandler.class.getName();

	setLevel(manager.getLevelProperty(cname +".level", Level.INFO));
	setFilter(manager.getFilterProperty(cname +".filter", null));
	setFormatter(manager.getFormatterProperty(cname +".formatter", new SimpleFormatter()));
	try {
	    setEncoding(manager.getStringProperty(cname +".encoding", null));
	} catch (Exception ex) {
	    try {
	        setEncoding(null);
	    } catch (Exception ex2) {
		// doing a setEncoding with null should always work.
		// assert false;
	    }
	}
    }

    /**
     * Create a <tt>ConsoleHandler</tt> for <tt>System.err</tt>.
     * <p>
     * The <tt>ConsoleHandler</tt> is configured based on
     * <tt>LogManager</tt> properties (or their default values).
     * 
     */
    public ConsoleHandler() {
	sealed = false;
	configure();
	setOutputStream(System.err);
	sealed = true;
    }

    /**
     * Publish a <tt>LogRecord</tt>.
     * <p>
     * The logging request was made initially to a <tt>Logger</tt> object,
     * which initialized the <tt>LogRecord</tt> and forwarded it here.
     * <p>
     * @param  record  description of the log event
     */
    public void publish(LogRecord record) {
	super.publish(record);	
	flush();
    }

    /**
     * Override <tt>StreamHandler.close</tt> to do a flush but not
     * to close the output stream.  That is, we do <b>not</b>
     * close <tt>System.err</tt>.
     */
    public void close() {
	flush();
    }
}