/*
 * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//logging/src/java/org/apache/commons/logging/Attic/SimpleLog.java,v 1.12 2002/01/31 00:14:31 sanders Exp $
 * $Revision: 1.12 $
 * $Date: 2002/01/31 00:14:31 $
 *
 * ====================================================================
 *
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999-2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */


package org.apache.commons.logging;

import java.util.Properties;
import java.util.Enumeration;
import java.io.InputStream;
import java.text.SimpleDateFormat;
import java.text.DateFormat;
import java.util.Date;

/**
 * <p>Simple implementation of Log that sends all enabled log messages,
 * for all defined loggers, to System.out.  The following system properties
 * are supported to configure the behavior of this logger:</p>
 * <ul>
 * <li><code>org.apache.commons.logging.simplelog.defaultlog</code> -
 *     Default logging detail level for all instances of SimpleLog.
 *     Must be one of ("trace", "debug", "info", "warn", "error", or "fatal").
 *     If not specified, defaults to "error". </li>
 * <li><code>org.apache.commons.logging.simplelog.log.xxxxx</code> -
 *     Logging detail level for a SimpleLog instance named "xxxxx".
 *     Must be one of ("trace", "debug", "info", "warn", "error", or "fatal").
 *     If not specified, the default logging detail level is used.</li>
 * <li><code>org.apache.commons.logging.simplelog.showlogname</code> -
 *     Set to <code>true</code> if you want the Log instance name to be
 *     included in output messages.</li>
 * <li><code>org.apache.commons.logging.simplelog.showdatetime</code> -
 *     Set to <code>true</code> if you want the current date and time
 *     to be included in output messages.</li>
 * </ul>
 *
 * <p>In addition to looking for system properties with the names specified
 * above, this implementation also checks for a class loader resource named
 * <code>"simplelog.properties"</code>, and includes any matching definitions
 * from this resource (if it exists).</p>
 *
 * @author <a href="mailto:sanders@apache.org">Scott Sanders</a>
 * @author Rod Waldhoff
 * @author Robert Burrell Donkin
 *
 * @version $Id: SimpleLog.java,v 1.12 2002/01/31 00:14:31 sanders Exp $
 */
public class SimpleLog implements Log {


    // ------------------------------------------------------- Class Attributes

    /** All system properties used by <code>Simple</code> start with this */
    static protected final String systemPrefix =
        "org.apache.commons.logging.simplelog.";

    /** All system properties which start with {@link #systemPrefix} */
    static protected final Properties simpleLogProps = new Properties();
    /** Include the instance name in the log message? */
    static protected boolean showLogName = false;
    /** Include the current time in the log message */
    static protected boolean showDateTime = false;
    /** Used to format times */
    static protected DateFormat dateFormatter = null;

    // ---------------------------------------------------- Log Level Constants


    /** "Trace" level logging. */
    public static final int LOG_LEVEL_TRACE  = 1;
    /** "Debug" level logging. */
    public static final int LOG_LEVEL_DEBUG  = 2;
    /** "Info" level logging. */
    public static final int LOG_LEVEL_INFO   = 3;
    /** "Warn" level logging. */
    public static final int LOG_LEVEL_WARN   = 4;
    /** "Error" level logging. */
    public static final int LOG_LEVEL_ERROR  = 5;
    /** "Fatal" level logging. */
    public static final int LOG_LEVEL_FATAL  = 6;

    /** Enable all logging levels */
    public static final int LOG_LEVEL_ALL    = (LOG_LEVEL_TRACE - 1);

    /** Enable no logging levels */
    public static final int LOG_LEVEL_OFF    = (LOG_LEVEL_FATAL + 1);

    // ------------------------------------------------------------ Initializer

    // initialize class attributes
    static {
        // add all system props that start with the specified prefix
        Enumeration enum = System.getProperties().propertyNames();
        while(enum.hasMoreElements()) {
            String name = (String)(enum.nextElement());
            if(null != name && name.startsWith(systemPrefix)) {
                simpleLogProps.setProperty(name,System.getProperty(name));
            }
        }

        // add props from the resource simplelog.properties
        InputStream in =
            ClassLoader.getSystemResourceAsStream("simplelog.properties");
        if(null != in) {
            try {
                simpleLogProps.load(in);
                in.close();
            } catch(java.io.IOException e) {
                // ignored
            }
        }

        showLogName = "true".equalsIgnoreCase(
                simpleLogProps.getProperty(
                    systemPrefix + "showlogname","true"));

        showDateTime = "true".equalsIgnoreCase(
                simpleLogProps.getProperty(
                    systemPrefix + "showdatetime","true"));

        if(showDateTime) {
            dateFormatter = new SimpleDateFormat(
                simpleLogProps.getProperty(
                    systemPrefix + "dateformat","yyyy/MM/dd HH:mm:ss:SSS zzz"));
        }
    }


    // ------------------------------------------------------------- Attributes

    /** The name of this simple log instance */
    protected String logName = null;
    /** The current log level */
    protected int currentLogLevel;


    // ------------------------------------------------------------ Constructor

    /**
     * Construct a simple log with given name.
     *
     * @param name log name
     */
    public SimpleLog(String name) {

        logName = name;

        // set initial log level
        // set default log level to ERROR
        setLevel(SimpleLog.LOG_LEVEL_ERROR);

        // set log level from properties
        String lvl = simpleLogProps.getProperty(systemPrefix + "log." + logName);
        int i = String.valueOf(name).lastIndexOf(".");
        while(null == lvl && i > -1) {
            name = name.substring(0,i);
            lvl = simpleLogProps.getProperty(systemPrefix + "log." + name);
            i = String.valueOf(name).lastIndexOf(".");
        }

        if(null == lvl) {
            lvl =  simpleLogProps.getProperty(systemPrefix + "defaultlog");
        }

        if("all".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_ALL);
        } else if("trace".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_TRACE);
        } else if("debug".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_DEBUG);
        } else if("info".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_INFO);
        } else if("warn".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_WARN);
        } else if("error".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_ERROR);
        } else if("fatal".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_FATAL);
        } else if("off".equalsIgnoreCase(lvl)) {
            setLevel(SimpleLog.LOG_LEVEL_OFF);
        }

    }


    // -------------------------------------------------------- Properties

    /**
     * <p> Set logging level. </p>
     *
     * @param level new logging level
     */
    public void setLevel(int currentLogLevel) {

        this.currentLogLevel = currentLogLevel;
    }


    /**
     * <p> Get logging level. </p>
     */
    public int getLevel() {

        return currentLogLevel;
    }


    // -------------------------------------------------------- Logging Methods


    /**
     * <p> Do the actual logging.
     * This method assembles the message
     * and then prints to <code>System.out</code>.</p>
     */
    protected void log(int type, Object message, Throwable t) {
        // use a string buffer for better performance
        StringBuffer buf = new StringBuffer();

        // append date-time if so configured
        if(showDateTime) {
            buf.append(dateFormatter.format(new Date()));
            buf.append(" ");
        }

        // append a readable representation of the log leve
        switch(type) {
            case SimpleLog.LOG_LEVEL_TRACE: buf.append("[TRACE] "); break;
            case SimpleLog.LOG_LEVEL_DEBUG: buf.append("[DEBUG] "); break;
            case SimpleLog.LOG_LEVEL_INFO:  buf.append("[INFO] ");  break;
            case SimpleLog.LOG_LEVEL_WARN:  buf.append("[WARN] ");  break;
            case SimpleLog.LOG_LEVEL_ERROR: buf.append("[ERROR] "); break;
            case SimpleLog.LOG_LEVEL_FATAL: buf.append("[FATAL] "); break;
        }

        // append the name of the log instance if so configured
        if(showLogName) {
            buf.append(String.valueOf(logName)).append(" - ");
        }

        // append the message
        buf.append(String.valueOf(message));

        // append stack trace if not null
        if(t != null) {
            buf.append(" <");
            buf.append(t.toString());
            buf.append(">");
            t.printStackTrace();
        }

        // print to System.out
        System.out.println(buf.toString());
    }


    /**
     * Is the given log level currently enabled?
     *
     * @param logLevel is this level enabled?
     */
    protected boolean isLevelEnabled(int logLevel) {
        // log level are numerically ordered so can use simple numeric
        // comparison
        return (logLevel >= currentLogLevel);
    }


    // -------------------------------------------------------- Log Implementation


    /**
     * <p> Log a message with debug log level.</p>
     */
    public final void debug(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG)) {
            log(SimpleLog.LOG_LEVEL_DEBUG, message, null);
        }
    }


    /**
     * <p> Log an error with debug log level.</p>
     */
    public final void debug(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG)) {
            log(SimpleLog.LOG_LEVEL_DEBUG, message, t);
        }
    }


    /**
     * <p> Log a message with debug log level.</p>
     */
    public final void trace(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE)) {
            log(SimpleLog.LOG_LEVEL_TRACE, message, null);
        }
    }


    /**
     * <p> Log an error with debug log level.</p>
     */
    public final void trace(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE)) {
            log(SimpleLog.LOG_LEVEL_TRACE, message, t);
        }
    }


    /**
     * <p> Log a message with info log level.</p>
     */
    public final void info(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_INFO)) {
            log(SimpleLog.LOG_LEVEL_INFO,message,null);
        }
    }


    /**
     * <p> Log an error with info log level.</p>
     */
    public final void info(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_INFO)) {
            log(SimpleLog.LOG_LEVEL_INFO, message, t);
        }
    }


    /**
     * <p> Log a message with warn log level.</p>
     */
    public final void warn(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_WARN)) {
            log(SimpleLog.LOG_LEVEL_WARN, message, null);
        }
    }


    /**
     * <p> Log an error with warn log level.</p>
     */
    public final void warn(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_WARN)) {
            log(SimpleLog.LOG_LEVEL_WARN, message, t);
        }
    }


    /**
     * <p> Log a message with error log level.</p>
     */
    public final void error(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR)) {
            log(SimpleLog.LOG_LEVEL_ERROR, message, null);
        }
    }


    /**
     * <p> Log an error with error log level.</p>
     */
    public final void error(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR)) {
            log(SimpleLog.LOG_LEVEL_ERROR, message, t);
        }
    }


    /**
     * <p> Log a message with fatal log level.</p>
     */
    public final void fatal(Object message) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL)) {
            log(SimpleLog.LOG_LEVEL_FATAL, message, null);
        }
    }


    /**
     * <p> Log an error with fatal log level.</p>
     */
    public final void fatal(Object message, Throwable t) {

        if (isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL)) {
            log(SimpleLog.LOG_LEVEL_FATAL, message, t);
        }
    }


    /**
     * <p> Are debug messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isDebugEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG);
    }


    /**
     * <p> Are error messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isErrorEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR);
    }


    /**
     * <p> Are fatal messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isFatalEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL);
    }


    /**
     * <p> Are info messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isInfoEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_INFO);
    }


    /**
     * <p> Are trace messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isTraceEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE);
    }


    /**
     * <p> Are warn messages currently enabled? </p>
     *
     * <p> This allows expensive operations such as <code>String</code>
     * concatenation to be avoided when the message will be ignored by the
     * logger. </p>
     */
    public final boolean isWarnEnabled() {

        return isLevelEnabled(SimpleLog.LOG_LEVEL_WARN);
    }
}