Log.java revision b35ea0d2d494ba7668b0183dfc906cde0708bc55 
1/*
2 * Copyright (C) 2014 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.android.ex.camera2.portability.debug;
18
19public class Log {
20    public static final String CAMERA_LOGTAG_PREFIX = "CAM2PORT_";
21    private static final Log.Tag TAG = new Log.Tag("Log");
22
23    /**
24     * This class restricts the length of the log tag to be less than the
25     * framework limit and also prepends the common tag prefix defined by
26     * {@code CAMERA_LOGTAG_PREFIX}.
27     */
28    public static final class Tag {
29
30        // The length limit from Android framework is 23.
31        private static final int MAX_TAG_LEN = 23 - CAMERA_LOGTAG_PREFIX.length();
32
33        final String mValue;
34
35        public Tag(String tag) {
36            final int lenDiff = tag.length() - MAX_TAG_LEN;
37            if (lenDiff > 0) {
38                w(TAG, "Tag " + tag + " is " + lenDiff + " chars longer than limit.");
39            }
40            mValue = CAMERA_LOGTAG_PREFIX + (lenDiff > 0 ? tag.substring(0, MAX_TAG_LEN) : tag);
41        }
42
43        @Override
44        public String toString() {
45            return mValue;
46        }
47    }
48
49    private interface Logger {
50        void log(Tag tag, String msg);
51        void log(Tag tag, String msg, Throwable tr);
52    }
53
54    private static final Logger SILENT_LOGGER = new Logger() {
55        @Override
56        public void log(Tag tag, String msg) {
57            // Do nothing.
58        }
59
60        @Override
61        public void log(Tag tag, String msg, Throwable tr) {
62            // Do nothing.
63        }
64    };
65
66    private static final Logger LOGGER_D = (!CurrentConfig.get().logDebug() ? SILENT_LOGGER : new Logger() {
67        final int level = android.util.Log.DEBUG;
68
69        @Override
70        public void log(Tag tag, String msg) {
71            if (isLoggable(tag, level)) {
72                android.util.Log.d(tag.toString(), msg);
73            }
74        }
75
76        @Override
77        public void log(Tag tag, String msg, Throwable tr) {
78            if (isLoggable(tag, level)) {
79                android.util.Log.d(tag.toString(), msg, tr);
80            }
81        }
82    });
83
84    private static final Logger LOGGER_E = (!CurrentConfig.get().logError() ? SILENT_LOGGER : new Logger() {
85        final int level = android.util.Log.ERROR;
86
87        @Override
88        public void log(Tag tag, String msg) {
89            if (isLoggable(tag, level)) {
90                android.util.Log.e(tag.toString(), msg);
91            }
92        }
93
94        @Override
95        public void log(Tag tag, String msg, Throwable tr) {
96            if (isLoggable(tag, level)) {
97                android.util.Log.e(tag.toString(), msg, tr);
98            }
99        }
100    });
101
102    private static final Logger LOGGER_I = (!CurrentConfig.get().logInfo() ? SILENT_LOGGER : new Logger() {
103        final int level = android.util.Log.INFO;
104
105        @Override
106        public void log(Tag tag, String msg) {
107            if (isLoggable(tag, level)) {
108                android.util.Log.i(tag.toString(), msg);
109            }
110        }
111
112        @Override
113        public void log(Tag tag, String msg, Throwable tr) {
114            if (isLoggable(tag, level)) {
115                android.util.Log.i(tag.toString(), msg, tr);
116            }
117        }
118    });
119
120    private static final Logger LOGGER_V = (!CurrentConfig.get().logVerbose() ? SILENT_LOGGER : new Logger() {
121        final int level = android.util.Log.VERBOSE;
122
123        @Override
124        public void log(Tag tag, String msg) {
125            if (isLoggable(tag, level)) {
126                android.util.Log.v(tag.toString(), msg);
127            }
128        }
129
130        @Override
131        public void log(Tag tag, String msg, Throwable tr) {
132            if (isLoggable(tag, level)) {
133                android.util.Log.v(tag.toString(), msg, tr);
134            }
135        }
136    });
137
138    private static final Logger LOGGER_W = (!CurrentConfig.get().logWarn() ? SILENT_LOGGER : new Logger() {
139        final int level = android.util.Log.WARN;
140
141        @Override
142        public void log(Tag tag, String msg) {
143            if (isLoggable(tag, level)) {
144                android.util.Log.w(tag.toString(), msg);
145            }
146        }
147
148        @Override
149        public void log(Tag tag, String msg, Throwable tr) {
150            if (isLoggable(tag, level)) {
151                android.util.Log.w(tag.toString(), msg, tr);
152            }
153        }
154    });
155
156
157    public static void d(Tag tag, String msg) {
158        LOGGER_D.log(tag, msg);
159    }
160
161    public static void d(Tag tag, String msg, Throwable tr) {
162        LOGGER_D.log(tag, msg, tr);
163    }
164
165    public static void e(Tag tag, String msg) {
166        LOGGER_E.log(tag, msg);
167    }
168
169    public static void e(Tag tag, String msg, Throwable tr) {
170        LOGGER_E.log(tag, msg, tr);
171    }
172
173    public static void i(Tag tag, String msg) {
174        LOGGER_I.log(tag, msg);
175    }
176
177    public static void i(Tag tag, String msg, Throwable tr) {
178        LOGGER_I.log(tag, msg, tr);
179    }
180
181    public static void v(Tag tag, String msg) {
182        LOGGER_V.log(tag, msg);
183    }
184
185    public static void v(Tag tag, String msg, Throwable tr) {
186        LOGGER_V.log(tag, msg, tr);
187    }
188
189    public static void w(Tag tag, String msg) {
190        LOGGER_W.log(tag, msg);
191    }
192
193    public static void w(Tag tag, String msg, Throwable tr) {
194        LOGGER_W.log(tag, msg, tr);
195    }
196
197    private static boolean isLoggable(Tag tag, int level) {
198        try {
199            return android.util.Log.isLoggable(tag.toString(), level);
200        } catch (IllegalArgumentException ex) {
201            e(TAG, "Tag too long:" + tag);
202            return false;
203        }
204    }
205}
206