1/*
2 * Copyright 2001-2004 The Apache Software Foundation.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package org.apache.log4j.spi;
18
19import org.apache.log4j.*;
20
21import java.util.Enumeration;
22
23/**
24 * A <code>LoggerRepository</code> is used to create and retrieve
25 * <code>Loggers</code>. The relation between loggers in a repository
26 * depends on the repository but typically loggers are arranged in a
27 * named hierarchy.
28 * <p/>
29 * <p>In addition to the creational methods, a
30 * <code>LoggerRepository</code> can be queried for existing loggers,
31 * can act as a point of registry for events related to loggers.
32 *
33 * @author Ceki G&uuml;lc&uuml;
34 * @since 1.2
35 */
36public interface LoggerRepository {
37
38    /**
39     * Add a {@link HierarchyEventListener} event to the repository.
40     */
41    public void addHierarchyEventListener(HierarchyEventListener listener);
42
43    /**
44     * Returns whether this repository is disabled for a given
45     * level. The answer depends on the repository threshold and the
46     * <code>level</code> parameter. See also {@link #setThreshold}
47     * method.
48     */
49    boolean isDisabled(int level);
50
51    /**
52     * Set the repository-wide threshold. All logging requests below the
53     * threshold are immediately dropped. By default, the threshold is
54     * set to <code>Level.ALL</code> which has the lowest possible rank.
55     */
56    public void setThreshold(Level level);
57
58    /**
59     * Another form of {@link #setThreshold(Level)} accepting a string
60     * parameter instead of a <code>Level</code>.
61     */
62    public void setThreshold(String val);
63
64    public void emitNoAppenderWarning(Category cat);
65
66    /**
67     * Get the repository-wide threshold. See {@link
68     * #setThreshold(Level)} for an explanation.
69     */
70    public Level getThreshold();
71
72    public Logger getLogger(String name);
73
74    public Logger getLogger(String name, LoggerFactory factory);
75
76    public Logger getRootLogger();
77
78    public abstract Logger exists(String name);
79
80    public abstract void shutdown();
81
82    @SuppressWarnings("rawtypes")
83    public Enumeration getCurrentLoggers();
84
85    /**
86     * Deprecated. Please use {@link #getCurrentLoggers} instead.
87     */
88    @SuppressWarnings("rawtypes")
89    public Enumeration getCurrentCategories();
90
91    public abstract void fireAddAppenderEvent(Category logger, Appender appender);
92
93    public abstract void resetConfiguration();
94
95}
96