| /* |
| * Copyright 2022 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package androidx.camera.previewview.internal.utils; |
| |
| import android.os.Build; |
| import android.util.Log; |
| |
| import androidx.annotation.IntRange; |
| import androidx.annotation.NonNull; |
| import androidx.annotation.RequiresApi; |
| |
| /** |
| * Handles logging requests inside CameraX. Log messages are output only if: |
| * - The minimum logging level allows for it. The minimum logging level is set via |
| * {@link #setMinLogLevel(int)}, which should typically be called during the process of configuring |
| * CameraX. |
| * - The log tag is {@linkplain Log#isLoggable(String, int) loggable}. This can be configured |
| * by setting the system property `setprop log.tag.TAG LEVEL`, where TAG is the log tag, and |
| * LEVEL is {@link Log#DEBUG}, {@link Log#INFO}, {@link Log#WARN} or {@link Log#ERROR}. |
| * <p> A typical usage of the Logger looks as follows: |
| * <pre> |
| * try { |
| * int quotient = dividend / divisor; |
| * } catch (ArithmeticException exception) { |
| * Logger.e(TAG, "Divide operation error", exception); |
| * } |
| * </pre> |
| * <p> If an action has to be performed alongside logging, or if building the log message is costly, |
| * perform a log level check before attempting to log. |
| * <pre> |
| * try { |
| * int quotient = dividend / divisor; |
| * } catch (ArithmeticException exception) { |
| * if (Logger.isErrorEnabled(TAG)) { |
| * Logger.e(TAG, "Divide operation error", exception); |
| * doSomething(); |
| * } |
| * } |
| * </pre> |
| */ |
| @RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java |
| public final class Logger { |
| |
| /** On API levels strictly below 24, the log tag's length must not exceed 23 characters. */ |
| private static final int MAX_TAG_LENGTH = 23; |
| |
| static final int DEFAULT_MIN_LOG_LEVEL = Log.DEBUG; |
| private static int sMinLogLevel = DEFAULT_MIN_LOG_LEVEL; |
| |
| private Logger() { |
| } |
| |
| /** |
| * Returns {@code true} if logging with the truncated tag {@code truncatedTag} is |
| * enabled at the {@code logLevel} level. |
| */ |
| private static boolean isLogLevelEnabled(@NonNull String truncatedTag, int logLevel) { |
| return sMinLogLevel <= logLevel || Log.isLoggable(truncatedTag, logLevel); |
| } |
| |
| /** |
| * Sets the minimum logging level to use in {@link Logger}. After calling this method, only logs |
| * at the level {@code logLevel} and above are output. |
| */ |
| static void setMinLogLevel(@IntRange(from = Log.DEBUG, to = Log.ERROR) int logLevel) { |
| sMinLogLevel = logLevel; |
| } |
| |
| /** |
| * Returns current minimum logging level. |
| */ |
| static int getMinLogLevel() { |
| return sMinLogLevel; |
| } |
| |
| /** |
| * Resets the minimum logging level to use in {@link Logger} to the default minimum logging |
| * level. After calling this method, only logs at the default level and above are output. |
| */ |
| static void resetMinLogLevel() { |
| sMinLogLevel = DEFAULT_MIN_LOG_LEVEL; |
| } |
| |
| /** |
| * Returns {@code true} if logging with the tag {@code tag} is enabled at the {@link Log#DEBUG} |
| * level. This is true when the minimum logging level is less than or equal to |
| * {@link Log#DEBUG}, or if the log level of {@code tag} was explicitly set to |
| * {@link Log#DEBUG} at least. |
| */ |
| public static boolean isDebugEnabled(@NonNull String tag) { |
| return isLogLevelEnabled(truncateTag(tag), Log.DEBUG); |
| } |
| |
| /** |
| * Returns {@code true} if logging with the tag {@code tag} is enabled at the {@link Log#INFO} |
| * level. This is true when the minimum logging level is less than or equal to |
| * {@link Log#INFO}, or if the log level of {@code tag} was explicitly set to |
| * {@link Log#INFO} at least. |
| */ |
| public static boolean isInfoEnabled(@NonNull String tag) { |
| return isLogLevelEnabled(truncateTag(tag), Log.INFO); |
| } |
| |
| /** |
| * Returns {@code true} if logging with the tag {@code tag} is enabled at the {@link Log#WARN} |
| * level. This is true when the minimum logging level is less than or equal to |
| * {@link Log#WARN}, or if the log level of {@code tag} was explicitly set to |
| * {@link Log#WARN} at least. |
| */ |
| public static boolean isWarnEnabled(@NonNull String tag) { |
| return isLogLevelEnabled(truncateTag(tag), Log.WARN); |
| } |
| |
| /** |
| * Returns {@code true} if logging with the tag {@code tag} is enabled at the {@link Log#ERROR} |
| * level. This is true when the minimum logging level is less than or equal to |
| * {@link Log#ERROR}, or if the log level of {@code tag} was explicitly set to |
| * {@link Log#ERROR} at least. |
| */ |
| public static boolean isErrorEnabled(@NonNull String tag) { |
| return isLogLevelEnabled(truncateTag(tag), Log.ERROR); |
| } |
| |
| /** |
| * Logs the given {@link Log#DEBUG} message if the tag is |
| * {@linkplain #isDebugEnabled(String) loggable}. |
| */ |
| public static void d(@NonNull String tag, @NonNull String message) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.DEBUG)) { |
| Log.d(truncatedTag, message); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#DEBUG} message and the exception's stacktrace if the tag is |
| * {@linkplain #isDebugEnabled(String) loggable}. |
| */ |
| public static void d(@NonNull String tag, @NonNull String message, |
| @NonNull final Throwable throwable) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.DEBUG)) { |
| Log.d(truncatedTag, message, throwable); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#INFO} message if the tag is |
| * {@linkplain #isInfoEnabled(String) loggable}. |
| */ |
| public static void i(@NonNull String tag, @NonNull String message) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.INFO)) { |
| Log.i(truncatedTag, message); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#INFO} message and the exception's stacktrace if the tag is |
| * {@linkplain #isInfoEnabled(String) loggable}. |
| */ |
| public static void i(@NonNull String tag, @NonNull String message, |
| @NonNull final Throwable throwable) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.INFO)) { |
| Log.i(truncatedTag, message, throwable); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#WARN} message if the tag is |
| * {@linkplain #isWarnEnabled(String) loggable}. |
| */ |
| public static void w(@NonNull String tag, @NonNull String message) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.WARN)) { |
| Log.w(truncatedTag, message); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#WARN} message and the exception's stacktrace if the tag is |
| * {@linkplain #isWarnEnabled(String) loggable}. |
| */ |
| public static void w(@NonNull String tag, @NonNull String message, |
| @NonNull final Throwable throwable) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.WARN)) { |
| Log.w(truncatedTag, message, throwable); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#ERROR} message if the tag is |
| * {@linkplain #isErrorEnabled(String) loggable}. |
| */ |
| public static void e(@NonNull String tag, @NonNull String message) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.ERROR)) { |
| Log.e(truncatedTag, message); |
| } |
| } |
| |
| /** |
| * Logs the given {@link Log#ERROR} message and the exception's stacktrace if the tag is |
| * {@linkplain #isErrorEnabled(String) loggable}. |
| */ |
| public static void e(@NonNull String tag, @NonNull String message, |
| @NonNull final Throwable throwable) { |
| final String truncatedTag = truncateTag(tag); |
| if (isLogLevelEnabled(truncatedTag, Log.ERROR)) { |
| Log.e(truncatedTag, message, throwable); |
| } |
| } |
| |
| /** |
| * Truncates the tag so it can be used to log. |
| * <p> |
| * On API 24, the tag length limit of 23 characters was removed. |
| */ |
| @NonNull |
| private static String truncateTag(@NonNull String tag) { |
| if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N && MAX_TAG_LENGTH < tag.length()) { |
| return tag.substring(0, MAX_TAG_LENGTH); |
| } |
| return tag; |
| } |
| } |
