/* * 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.*; import org.apache.log4j.helpers.LogLog; // Contibutors: Mathias Bogaert /** RootLogger sits at the top of the logger hierachy. 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. @author Ceki Gülcü */ 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) { super("root"); setLevel(level); } /** Return the assigned level value without walking the logger hierarchy. */ public final Level getChainedLevel() { return 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 { this.level = level; } } }