/*
* Copyright (c) 2004-2008 QOS.ch
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package org.slf4j;
import org.slf4j.helpers.NOPLoggerFactory;
import org.slf4j.impl.StaticLoggerBinder;
/**
* The <code>LoggerFactory</code> is a utility class producing Loggers for
* various logging APIs, most notably for log4j, logback and JDK 1.4 logging.
* Other implementations such as {@link org.slf4j.impl.NOPLogger NOPLogger} and
* {@link org.slf4j.impl.SimpleLogger SimpleLogger} are also supported.
*
* <p>
* <code>LoggerFactory</code> is essentially a wrapper around an
* {@link ILoggerFactory} instance bound with <code>LoggerFactory</code> at
* compile time.
*
* <p>
* Please note that all methods in <code>LoggerFactory</code> are static.
*
* <p>
* This is a reduced an modified version to support CLDC 1.1
*
* @author Ceki Gülcü
* @author Robert Elliot
* @author Marcel Patzlaff
*/
public final class LoggerFactory {
static final String UNSUCCESSFUL_INIT_MSG= "org.slf4j.LoggerFactory could not be successfully initialized.";
static final int UNINITIALIZED= 0;
static final int ONGOING_INITILIZATION= 1;
static final int FAILED_INITILIZATION= 2;
static final int SUCCESSFUL_INITILIZATION= 3;
static final int NOP_FALLBACK_INITILIZATION= 4;
static int INITIALIZATION_STATE= UNINITIALIZED;
static final NOPLoggerFactory NOP_FALLBACK_FACTORY;
static {
NOP_FALLBACK_FACTORY= new NOPLoggerFactory();
}
// private constructor prevents instantiation
private LoggerFactory() {
}
private final static void bind() {
try {
// the next line does the binding
StaticLoggerBinder.getSingleton();
INITIALIZATION_STATE= SUCCESSFUL_INITILIZATION;
} catch (NoClassDefFoundError ncde) {
String msg= ncde.getMessage();
if (msg != null && msg.indexOf("org/slf4j/impl/StaticLoggerBinder") != -1) {
INITIALIZATION_STATE= NOP_FALLBACK_INITILIZATION;
System.err.println("Defaulting to no-operation (NOP) logger implementation");
} else {
failedBinding(ncde);
throw ncde;
}
} catch (java.lang.Error nsme) {
String msg= nsme.getMessage();
if (msg != null && msg.indexOf("org.slf4j.impl.StaticLoggerBinder.getSingleton()") != -1) {
INITIALIZATION_STATE= FAILED_INITILIZATION;
System.err.println("slf4j-cldc-api 1.6.x (or later) is incompatible with this binding.");
System.err.println("Your binding is version 1.5.5 or earlier.");
System.err.println("Upgrade your binding to version 1.6.x. or 2.0.x");
}
throw nsme;
} catch (Exception e) {
failedBinding(e);
throw new RuntimeException("Unexpected initialization failure: " + e.getMessage());
}
}
static void failedBinding(Throwable t) {
INITIALIZATION_STATE= FAILED_INITILIZATION;
System.err.println("Failed to instantiate SLF4J LoggerFactory");
t.printStackTrace();
}
/**
* Return a logger named according to the name parameter using the
* statically bound {@link ILoggerFactory} instance.
*
* @param name
* The name of the logger.
* @return logger
*/
public static Logger getLogger(String name) {
ILoggerFactory iLoggerFactory= getILoggerFactory();
return iLoggerFactory.getLogger(name);
}
/**
* Return a logger named corresponding to the class passed as parameter,
* using the statically bound {@link ILoggerFactory} instance.
*
* @param clazz
* the returned logger will be named after clazz
* @return logger
*/
public static Logger getLogger(Class clazz) {
return getLogger(clazz.getName());
}
/**
* Return the {@link ILoggerFactory} instance in use.
*
* <p>
* ILoggerFactory instance is bound with this class at compile time.
*
* @return the ILoggerFactory instance in use
*/
public static ILoggerFactory getILoggerFactory() {
if (INITIALIZATION_STATE == UNINITIALIZED) {
INITIALIZATION_STATE= ONGOING_INITILIZATION;
bind();
}
switch (INITIALIZATION_STATE) {
case SUCCESSFUL_INITILIZATION:
return StaticLoggerBinder.getSingleton().getLoggerFactory();
case NOP_FALLBACK_INITILIZATION:
return NOP_FALLBACK_FACTORY;
case FAILED_INITILIZATION:
throw new RuntimeException(UNSUCCESSFUL_INIT_MSG);
case ONGOING_INITILIZATION:
// support re-entrant behavior.
// See also http://bugzilla.slf4j.org/show_bug.cgi?id=106
return NOP_FALLBACK_FACTORY;
}
throw new RuntimeException("Unreachable code");
}
}