maven-slf4j-provider/src/main/java/org/slf4j/impl/StaticLoggerBinder.java

package org.slf4j.impl;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import org.slf4j.ILoggerFactory;
import org.slf4j.spi.LoggerFactoryBinder;

/**
 * SLF4J LoggerFactoryBinder implementation using MavenSimpleLogger.
 * This class is part of the required classes used to specify an
 * SLF4J logger provider implementation.
 *
 * @since 3.5.1
 */
public final class StaticLoggerBinder
    implements LoggerFactoryBinder
{
    /**
     * Declare the version of the SLF4J API this implementation is compiled
     * against. The value of this field is usually modified with each release.
     */
    // to avoid constant folding by the compiler, this field must *not* be final
    @SuppressWarnings( { "checkstyle:staticvariablename", "checkstyle:visibilitymodifier" } )
    public static String REQUESTED_API_VERSION = "1.7.25"; // !final

    private static final String LOGGER_FACTORY_CLASS_STR = MavenLoggerFactory.class.getName();

    /**
     * The unique instance of this class.
     */
    private static final StaticLoggerBinder SINGLETON = new StaticLoggerBinder();

    /**
     * The ILoggerFactory instance returned by the {@link #getLoggerFactory}
     * method should always be the same object
     */
    private final ILoggerFactory loggerFactory;

    /**
     * Private constructor to prevent instantiation
     */
    private StaticLoggerBinder()
    {
        loggerFactory = new MavenLoggerFactory();
    }

    /**
     * Returns the singleton of this class.
     */
    public static StaticLoggerBinder getSingleton()
    {
        return SINGLETON;
    }

    /**
     * Returns the factory.
     */
    @Override
    public ILoggerFactory getLoggerFactory()
    {
        return loggerFactory;
    }

    /**
     * Returns the class name.
     */
    @Override
    public String getLoggerFactoryClassStr()
    {
        return LOGGER_FACTORY_CLASS_STR;
    }
}