Copyright (c) 2004-2011 QOS.ch
All rights reserved.
Permission is hereby granted, free  of charge, to any person obtaining
a  copy  of this  software  and  associated  documentation files  (the
"Software"), to  deal in  the Software without  restriction, including
without limitation  the rights to  use, copy, modify,  merge, publish,
distribute,  sublicense, and/or sell  copies of  the Software,  and to
permit persons to whom the Software  is furnished to do so, subject to
the following conditions:
The  above  copyright  notice  and  this permission  notice  shall  be
included in all copies or substantial portions of the Software.
THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
/**
 * Copyright (c) 2004-2011 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */
package org.slf4j;

import java.io.Serializable;
import java.util.Iterator;

Markers are named objects used to enrich log statements. Conforming logging
system Implementations of SLF4J determine how information conveyed by markers
are used, if at all. In particular, many conforming logging systems ignore
marker data.

Markers can contain references to other markers, which in turn may contain 
references of their own.
Author:
Ceki Gülcü/**
 * Markers are named objects used to enrich log statements. Conforming logging
 * system Implementations of SLF4J determine how information conveyed by markers
 * are used, if at all. In particular, many conforming logging systems ignore
 * marker data.
 * 
 * <p>
 * Markers can contain references to other markers, which in turn may contain 
 * references of their own.
 * 
 * @author Ceki G&uuml;lc&uuml;
 */
public interface Marker extends Serializable {

    
This constant represents any marker, including a null marker.
/**
     * This constant represents any marker, including a null marker.
     */
    public final String ANY_MARKER = "*";

    
This constant represents any non-null marker.
/**
     * This constant represents any non-null marker.
     */
    public final String ANY_NON_NULL_MARKER = "+";

    
Get the name of this Marker.
Returns:
name of marker/**
     * Get the name of this Marker.
     * 
     * @return name of marker
     */
    public String getName();

    
Add a reference to another Marker.
Params:
reference – 
               a reference to another marker
Throws:
IllegalArgumentException – 
                if 'reference' is null/**
     * Add a reference to another Marker.
     * 
     * @param reference
     *                a reference to another marker
     * @throws IllegalArgumentException
     *                 if 'reference' is null
     */
    public void add(Marker reference);

    
Remove a marker reference.
Params:
reference – 
               the marker reference to remove
Returns:
true if reference could be found and removed, false otherwise./**
     * Remove a marker reference.
     * 
     * @param reference
     *                the marker reference to remove
     * @return true if reference could be found and removed, false otherwise.
     */
    public boolean remove(Marker reference);

    
Deprecated:
Replaced by hasReferences()./**
     * @deprecated Replaced by {@link #hasReferences()}.
     */
    public boolean hasChildren();

    
Does this marker have any references?
Returns:
true if this marker has one or more references, false otherwise./**
     * Does this marker have any references?
     * 
     * @return true if this marker has one or more references, false otherwise.
     */
    public boolean hasReferences();

    
Returns an Iterator which can be used to iterate over the references of this
marker. An empty iterator is returned when this marker has no references.
Returns:
Iterator over the references of this marker/**
     * Returns an Iterator which can be used to iterate over the references of this
     * marker. An empty iterator is returned when this marker has no references.
     * 
     * @return Iterator over the references of this marker
     */
    public Iterator<Marker> iterator();

    
Does this marker contain a reference to the 'other' marker? Marker A is defined 
to contain marker B, if A == B or if B is referenced by A, or if B is referenced
by any one of A's references (recursively).
Params:
other – 
               The marker to test for inclusion.
Throws:
IllegalArgumentException – 
                if 'other' is null
Returns:
Whether this marker contains the other marker./**
     * Does this marker contain a reference to the 'other' marker? Marker A is defined 
     * to contain marker B, if A == B or if B is referenced by A, or if B is referenced
     * by any one of A's references (recursively).
     * 
     * @param other
     *                The marker to test for inclusion.
     * @throws IllegalArgumentException
     *                 if 'other' is null
     * @return Whether this marker contains the other marker.
     */
    public boolean contains(Marker other);

    
Does this marker contain the marker named 'name'?
If 'name' is null the returned value is always false.
Params:
name – The marker name to test for inclusion.
Returns:
Whether this marker contains the other marker./**
     * Does this marker contain the marker named 'name'?
     * 
     * If 'name' is null the returned value is always false.
     * 
     * @param name The marker name to test for inclusion.
     * @return Whether this marker contains the other marker.
     */
    public boolean contains(String name);

    
Markers are considered equal if they have the same name.
Params:
o – 
Returns:
true, if this.name equals o.name
Since:
1.5.1/**
     * Markers are considered equal if they have the same name.
     *
     * @param o
     * @return true, if this.name equals o.name
     *
     * @since 1.5.1
     */
    public boolean equals(Object o);

    
Compute the hash code based on the name of this marker.
Note that markers are considered equal if they have the same name.
Returns:
the computed hashCode
Since:
1.5.1/**
     * Compute the hash code based on the name of this marker.
     * Note that markers are considered equal if they have the same name.
     * 
     * @return the computed hashCode
     * @since 1.5.1
     */
    public int hashCode();

}