Logger.java revision 8d6d2581ff11ec169cd84a6610557b9afdf41e06 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
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 com.example.android.voicemail.common.logging;
18
19import android.util.Log;
20
21/**
22 * Simplifies usage of Android logging class {@link Log} by abstracting the TAG field that is
23 * required to be passed to every logging method. Also, allows automatic insertion of the owner
24 * class name prefix to log outputs for better debugging.
25 * <p>
26 * Use {@link #getLogger(Class)} to create an instance of Logger that automatically inserts the
27 * class name as a prefix to each log output. If you do not want the class name to be prefixed to
28 * log output then use {@link #getLogger()} to create the instance of Logger.
29 */
30public class Logger {
31    private static final String APP_TAG = "VoicemailSample";
32
33    /**
34     * Use this method if you want your class name to be prefixed to each log output.
35     */
36    public static Logger getLogger(Class<?> classZ) {
37        return new Logger(classZ.getSimpleName() + ": ");
38    }
39
40    /**
41     * Use this factory method if you DO NOT want your class name to be prefixed into the log
42     * output.
43     */
44    public static Logger getLogger() {
45        return new Logger();
46    }
47
48    private final String mLogPrefix;
49
50    /** No custom log prefix used. */
51    private Logger() {
52        mLogPrefix = null;
53    }
54
55    /** Use the supplied custom prefix in log output. */
56    private Logger(String logPrefix) {
57        mLogPrefix = logPrefix;
58    }
59
60    private String getMsg(String msg) {
61        if (mLogPrefix != null) {
62            return mLogPrefix + msg;
63        } else {
64            return msg;
65        }
66    }
67
68    public void i(String msg) {
69        Log.i(APP_TAG, getMsg(msg));
70    }
71
72    public void i(String msg, Throwable t) {
73        Log.i(APP_TAG, getMsg(msg), t);
74    }
75
76    public void d(String msg) {
77        Log.d(APP_TAG, getMsg(msg));
78    }
79
80    public void d(String msg, Throwable t) {
81        Log.d(APP_TAG, getMsg(msg), t);
82    }
83
84    public void w(String msg) {
85        Log.w(APP_TAG, getMsg(msg));
86    }
87
88    public void w(String msg, Throwable t) {
89        Log.w(APP_TAG, getMsg(msg), t);
90    }
91
92    public void e(String msg) {
93        Log.e(APP_TAG, getMsg(msg));
94    }
95
96    public void e(String msg, Throwable t) {
97        Log.e(APP_TAG, getMsg(msg), t);
98    }
99}
100