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 * 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
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package org.apache.logging.log4j.core;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.Marker;
import org.apache.logging.log4j.message.Message;
import org.apache.logging.log4j.util.EnglishEnums;

Interface that must be implemented to allow custom event filtering. It is highly recommended that
applications make use of the Filters provided with this implementation before creating their own.
This interface supports "global" filters (i.e. - all events must pass through them first), attached to
specific loggers and associated with Appenders. It is recommended that, where possible, Filter implementations
create a generic filtering method that can be called from any of the filter methods.
/**
 * Interface that must be implemented to allow custom event filtering. It is highly recommended that
 * applications make use of the Filters provided with this implementation before creating their own.
 *
 * <p>This interface supports "global" filters (i.e. - all events must pass through them first), attached to
 * specific loggers and associated with Appenders. It is recommended that, where possible, Filter implementations
 * create a generic filtering method that can be called from any of the filter methods.</p>
 */
public interface Filter extends LifeCycle {

    
Main plugin element type for Filter plugins. 
Since:
2.1/**
     * Main {@linkplain org.apache.logging.log4j.core.config.plugins.Plugin#elementType() plugin element type} for
     * Filter plugins.
     *
     * @since 2.1
     */
    String ELEMENT_TYPE = "filter";

    
The result that can returned from a filter method call.
/**
     * The result that can returned from a filter method call.
     */
     enum Result {
        
The event will be processed without further filtering based on the log Level.
/**
         * The event will be processed without further filtering based on the log Level.
         */
        ACCEPT,
        
No decision could be made, further filtering should occur.
/**
         * No decision could be made, further filtering should occur.
         */
        NEUTRAL,
        
The event should not be processed.
/**
         * The event should not be processed.
         */
        DENY;

        
Returns the Result for the given string.
Params:
name – The Result enum name, case-insensitive. If null, returns, null
Returns:
a Result enum value or null if name is null/**
         * Returns the Result for the given string.
         *
         * @param name The Result enum name, case-insensitive. If null, returns, null
         * @return a Result enum value or null if name is null
         */
        public static Result toResult(final String name) {
            return toResult(name, null);
        }

        
Returns the Result for the given string.
Params:
name – The Result enum name, case-insensitive. If null, returns, defaultResult
defaultResult – the Result to return if name is null
Returns:
a Result enum value or null if name is null/**
         * Returns the Result for the given string.
         *
         * @param name The Result enum name, case-insensitive. If null, returns, defaultResult
         * @param defaultResult the Result to return if name is null
         * @return a Result enum value or null if name is null
         */
        public static Result toResult(final String name, final Result defaultResult) {
            return EnglishEnums.valueOf(Result.class, name, defaultResult);
        }
}

    
Returns the result that should be returned when the filter does not match the event.
Returns:
the Result that should be returned when the filter does not match the event./**
     * Returns the result that should be returned when the filter does not match the event.
     * @return the Result that should be returned when the filter does not match the event.
     */
    Result getOnMismatch();
    
Returns the result that should be returned when the filter matches the event.
Returns:
the Result that should be returned when the filter matches the event./**
     * Returns the result that should be returned when the filter matches the event.
     * @return the Result that should be returned when the filter matches the event.
     */
    Result getOnMatch();

    
Filter an event.
Params:
logger – The Logger.
level – The event logging Level.
marker – The Marker for the event or null.
msg – String text to filter on.
params – An array of parameters or null.
Returns:
the Result./**
     * Filter an event.
     * @param logger The Logger.
     * @param level The event logging Level.
     * @param marker The Marker for the event or null.
     * @param msg String text to filter on.
     * @param params An array of parameters or null.
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String msg, Object... params);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
p5 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @param p5 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4, Object p5);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
p5 – the message parameters
p6 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @param p5 the message parameters
     * @param p6 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4, Object p5, Object p6);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
p5 – the message parameters
p6 – the message parameters
p7 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @param p5 the message parameters
     * @param p6 the message parameters
     * @param p7 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4, Object p5, Object p6, Object p7);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
p5 – the message parameters
p6 – the message parameters
p7 – the message parameters
p8 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @param p5 the message parameters
     * @param p6 the message parameters
     * @param p7 the message parameters
     * @param p8 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4, Object p5, Object p6, Object p7, Object p8);

    
Filter an event.
Params:
logger – The Logger.
level – the event logging level.
marker – The Marker for the event or null.
message – The message.
p0 – the message parameters
p1 – the message parameters
p2 – the message parameters
p3 – the message parameters
p4 – the message parameters
p5 – the message parameters
p6 – the message parameters
p7 – the message parameters
p8 – the message parameters
p9 – the message parameters
Returns:
the Result./**
     * Filter an event.
     *
     * @param logger The Logger.
     * @param level the event logging level.
     * @param marker The Marker for the event or null.
     * @param message The message.
     * @param p0 the message parameters
     * @param p1 the message parameters
     * @param p2 the message parameters
     * @param p3 the message parameters
     * @param p4 the message parameters
     * @param p5 the message parameters
     * @param p6 the message parameters
     * @param p7 the message parameters
     * @param p8 the message parameters
     * @param p9 the message parameters
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
            Object p4, Object p5, Object p6, Object p7, Object p8, Object p9);

    
Filter an event.
Params:
logger – The Logger.
level – The event logging Level.
marker – The Marker for the event or null.
msg – Any Object.
t – A Throwable or null.
Returns:
the Result./**
     * Filter an event.
     * @param logger The Logger.
     * @param level The event logging Level.
     * @param marker The Marker for the event or null.
     * @param msg Any Object.
     * @param t A Throwable or null.
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, Object msg, Throwable t);

    
Filter an event.
Params:
logger – The Logger.
level – The event logging Level.
marker – The Marker for the event or null.
msg – The Message
t – A Throwable or null.
Returns:
the Result./**
     * Filter an event.
     * @param logger The Logger.
     * @param level The event logging Level.
     * @param marker The Marker for the event or null.
     * @param msg The Message
     * @param t A Throwable or null.
     * @return the Result.
     */
    Result filter(Logger logger, Level level, Marker marker, Message msg, Throwable t);

    
Filter an event.
Params:
event – The Event to filter on.
Returns:
the Result./**
     * Filter an event.
     * @param event The Event to filter on.
     * @return the Result.
     */
    Result filter(LogEvent event);

}