1 package org.apache.velocity.runtime.log;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import org.apache.velocity.runtime.RuntimeServices;
23
24 /**
25 * Base interface that logging systems need to implement. This
26 * is the blessed descendant of the old LogSystem interface.
27 *
28 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
29 * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
30 * @author <a href="mailto:nbubna@apache.org">Nathan Bubna</a>
31 * @version $Id: LogChute.java 494611 2007-01-09 21:57:20Z henning $
32 */
33 public interface LogChute
34 {
35 /** Prefix string for trace messages. */
36 String TRACE_PREFIX = " [trace] ";
37
38 /** Prefix string for debug messages. */
39 String DEBUG_PREFIX = " [debug] ";
40
41 /** Prefix string for info messages. */
42 String INFO_PREFIX = " [info] ";
43
44 /** Prefix string for warn messages. */
45 String WARN_PREFIX = " [warn] ";
46
47 /** Prefix string for error messages. */
48 String ERROR_PREFIX = " [error] ";
49
50 /** ID for trace messages. */
51 int TRACE_ID = -1;
52
53 /** ID for debug messages. */
54 int DEBUG_ID = 0;
55
56 /** ID for info messages. */
57 int INFO_ID = 1;
58
59 /** ID for warning messages. */
60 int WARN_ID = 2;
61
62 /** ID for error messages. */
63 int ERROR_ID = 3;
64
65 /**
66 * Initializes this LogChute.
67 * @param rs
68 * @throws Exception
69 */
70 void init(RuntimeServices rs) throws Exception;
71
72 /**
73 * Send a log message from Velocity.
74 * @param level
75 * @param message
76 */
77 void log(int level, String message);
78
79 /**
80 * Send a log message from Velocity along with an exception or error
81 * @param level
82 * @param message
83 * @param t
84 */
85 void log(int level, String message, Throwable t);
86
87 /**
88 * Tell whether or not a log level is enabled.
89 * @param level
90 * @return True if a level is enabled.
91 */
92 boolean isLevelEnabled(int level);
93
94 }