org.apache.log4j.spi.RootLogger Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.log4j.spi;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.apache.log4j.helpers.LogLog;
/**
* RootLogger sits at the top of the logger hierarchy. It is a regular logger except that it provides several guarantees.
*
* First, it cannot be assigned a null level. Second, since root logger cannot have a parent, the
* {@link #getChainedLevel} method always returns the value of the level field without walking the hierarchy.
*
*/
public final class RootLogger extends Logger {
/**
* The root logger names itself as "root". However, the root logger cannot be retrieved by name.
*/
public RootLogger(Level level) {
// The Log4j 1 root logger name is "root".
// The Log4j 2 root logger name is "".
super("root");
setLevel(level);
}
/**
* Gets the assigned level value without walking the logger hierarchy.
*/
public final Level getChainedLevel() {
return getLevel();
}
/**
* Sets the log level.
*
* Setting a null value to the level of the root logger may have catastrophic results. We prevent this here.
*
* @since 0.8.3
*/
public final void setLevel(Level level) {
if (level == null) {
LogLog.error("You have tried to set a null level to root.", new Throwable());
} else {
super.setLevel(level);
}
}
}