Home | History | Annotate | Download | only in debug 
      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 
     17 package com.android.camera.debug;
     18 
     19 public class Log {
     20     /**
     21      * All Camera logging using this class will use this tag prefix.
     22      * Additionally, the prefix itself is checked in isLoggable and
     23      * serves as an override. So, to toggle all logs allowed by the
     24      * current {@link Configuration}, you can set properties:
     25      *
     26      * adb shell setprop log.tag.CAM_ VERBOSE
     27      * adb shell setprop log.tag.CAM_ ""
     28      */
     29     public static final String CAMERA_LOGTAG_PREFIX = "CAM_";
     30     private static final Log.Tag TAG = new Log.Tag("Log");
     31 
     32     /**
     33      * This class restricts the length of the log tag to be less than the
     34      * framework limit and also prepends the common tag prefix defined by
     35      * {@code CAMERA_LOGTAG_PREFIX}.
     36      */
     37     public static final class Tag {
     38 
     39         // The length limit from Android framework is 23.
     40         private static final int MAX_TAG_LEN = 23 - CAMERA_LOGTAG_PREFIX.length();
     41 
     42         final String mValue;
     43 
     44         public Tag(String tag) {
     45             final int lenDiff = tag.length() - MAX_TAG_LEN;
     46             if (lenDiff > 0) {
     47                 w(TAG, "Tag " + tag + " is " + lenDiff + " chars longer than limit.");
     48             }
     49             mValue = CAMERA_LOGTAG_PREFIX + (lenDiff > 0 ? tag.substring(0, MAX_TAG_LEN) : tag);
     50         }
     51 
     52         @Override
     53         public String toString() {
     54             return mValue;
     55         }
     56     }
     57 
     58     public static void d(Tag tag, String msg) {
     59         if (isLoggable(tag, android.util.Log.DEBUG)) {
     60             android.util.Log.d(tag.toString(), msg);
     61         }
     62     }
     63 
     64     public static void d(Tag tag, String msg, Throwable tr) {
     65         if (isLoggable(tag, android.util.Log.DEBUG)) {
     66             android.util.Log.d(tag.toString(), msg, tr);
     67         }
     68     }
     69 
     70     public static void e(Tag tag, String msg) {
     71         if (isLoggable(tag, android.util.Log.ERROR)) {
     72             android.util.Log.e(tag.toString(), msg);
     73         }
     74     }
     75 
     76     public static void e(Tag tag, String msg, Throwable tr) {
     77         if (isLoggable(tag, android.util.Log.ERROR)) {
     78             android.util.Log.e(tag.toString(), msg, tr);
     79         }
     80     }
     81 
     82     public static void i(Tag tag, String msg) {
     83         if (isLoggable(tag, android.util.Log.INFO)) {
     84             android.util.Log.i(tag.toString(), msg);
     85         }
     86     }
     87 
     88     public static void i(Tag tag, String msg, Throwable tr) {
     89         if (isLoggable(tag, android.util.Log.INFO)) {
     90             android.util.Log.i(tag.toString(), msg, tr);
     91         }
     92     }
     93 
     94     public static void v(Tag tag, String msg) {
     95         if (isLoggable(tag, android.util.Log.VERBOSE)) {
     96             android.util.Log.v(tag.toString(), msg);
     97         }
     98     }
     99 
    100     public static void v(Tag tag, String msg, Throwable tr) {
    101         if (isLoggable(tag, android.util.Log.VERBOSE)) {
    102             android.util.Log.v(tag.toString(), msg, tr);
    103         }
    104     }
    105 
    106     public static void w(Tag tag, String msg) {
    107         if (isLoggable(tag, android.util.Log.WARN)) {
    108             android.util.Log.w(tag.toString(), msg);
    109         }
    110     }
    111 
    112     public static void w(Tag tag, String msg, Throwable tr) {
    113         if (isLoggable(tag, android.util.Log.WARN)) {
    114             android.util.Log.w(tag.toString(), msg, tr);
    115         }
    116     }
    117 
    118     private static boolean isLoggable(Tag tag, int level) {
    119         try {
    120             if (LogHelper.getOverrideLevel() != 0) {
    121                 // Override system log level and output. VERBOSE is smaller than
    122                 // ERROR, so the comparison checks that the override value is smaller
    123                 // than the desired output level. This applies to all tags.
    124                 return LogHelper.getOverrideLevel() <= level;
    125             } else {
    126                 // The prefix can be used as an override tag to see all camera logs
    127                 return android.util.Log.isLoggable(CAMERA_LOGTAG_PREFIX, level)
    128                         || android.util.Log.isLoggable(tag.toString(), level);
    129             }
    130         } catch (IllegalArgumentException ex) {
    131             e(TAG, "Tag too long:" + tag);
    132             return false;
    133         }
    134     }
    135 }
    136