org.apache.logging.log4j.spi.LoggerContext 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.logging.log4j.spi;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.message.MessageFactory;
/**
* Anchor point for logging implementations.
*/
public interface LoggerContext {
/**
* Empty array.
*/
LoggerContext[] EMPTY_ARRAY = {};
/**
* Gets the anchor for some other context, such as a ClassLoader or ServletContext.
* @return The external context.
*/
Object getExternalContext();
/**
* Gets an ExtendedLogger using the fully qualified name of the Class as the Logger name.
* @param cls The Class whose name should be used as the Logger name.
* @return The logger.
* @since 2.14.0
*/
default ExtendedLogger getLogger(Class cls) {
final String canonicalName = cls.getCanonicalName();
return getLogger(canonicalName != null ? canonicalName : cls.getName());
}
/**
* Gets an ExtendedLogger using the fully qualified name of the Class as the Logger name.
* @param cls The Class whose name should be used as the Logger name.
* @param messageFactory The message factory is used only when creating a logger, subsequent use does not change the
* logger but will log a warning if mismatched.
* @return The logger.
* @since 2.14.0
*/
default ExtendedLogger getLogger(Class cls, MessageFactory messageFactory) {
final String canonicalName = cls.getCanonicalName();
return getLogger(canonicalName != null ? canonicalName : cls.getName(), messageFactory);
}
/**
* Gets an ExtendedLogger.
* @param name The name of the Logger to return.
* @return The logger with the specified name.
*/
ExtendedLogger getLogger(String name);
/**
* Gets an ExtendedLogger.
* @param name The name of the Logger to return.
* @param messageFactory The message factory is used only when creating a logger, subsequent use does not change
* the logger but will log a warning if mismatched.
* @return The logger with the specified name.
*/
ExtendedLogger getLogger(String name, MessageFactory messageFactory);
/**
* Gets the LoggerRegistry.
*
* @return the LoggerRegistry.
* @since 2.17.2
*/
default LoggerRegistry getLoggerRegistry() {
return null;
}
/**
* Gets an object by its name.
* @param key The object's key.
* @return The Object that is associated with the key, if any.
* @since 2.13.0
*/
default Object getObject(String key) {
return null;
}
/**
* Tests if a Logger with the specified name exists.
* @param name The Logger name to search for.
* @return true if the Logger exists, false otherwise.
*/
boolean hasLogger(String name);
/**
* Tests if a Logger with the specified name and MessageFactory type exists.
* @param name The Logger name to search for.
* @param messageFactoryClass The message factory class to search for.
* @return true if the Logger exists, false otherwise.
* @since 2.5
*/
boolean hasLogger(String name, Class messageFactoryClass);
/**
* Tests if a Logger with the specified name and MessageFactory exists.
* @param name The Logger name to search for.
* @param messageFactory The message factory to search for.
* @return true if the Logger exists, false otherwise.
* @since 2.5
*/
boolean hasLogger(String name, MessageFactory messageFactory);
/**
* Associates an object into the LoggerContext by name for later use.
* @param key The object's key.
* @param value The object.
* @return The previous object or null.
* @since 2.13.0
*/
default Object putObject(String key, Object value) {
return null;
}
/**
* Associates an object into the LoggerContext by name for later use if an object is not already stored with that key.
* @param key The object's key.
* @param value The object.
* @return The previous object or null.
* @since 2.13.0
*/
default Object putObjectIfAbsent(String key, Object value) {
return null;
}
/**
* Removes an object if it is present.
* @param key The object's key.
* @return The object if it was present, null if it was not.
* @since 2.13.0
*/
default Object removeObject(String key) {
return null;
}
/**
* Removes an object if it is present and the provided object is stored.
* @param key The object's key.
* @param value The object.
* @return The object if it was present, null if it was not.
* @since 2.13.0
*/
default boolean removeObject(String key, Object value) {
return false;
}
}