(#) Exception Logging !!! WARNING: Exception Logging This is a warning. Id : `TimberExceptionLogging` Summary : Exception Logging Severity : Warning Category : Correctness Platform : Any Vendor : JakeWharton/timber Identifier : com.jakewharton.timber:timber:{version} Feedback : https://github.com/JakeWharton/timber/issues Min : Lint 4.0 Compiled : Lint 7.0 Artifact : [com.jakewharton.timber:timber](com_jakewharton_timber_timber.md.html) Since : 4.6.0 Affects : Kotlin and Java files Editing : This check runs on the fly in the IDE editor Implementation : [Source Code](https://github.com/JakeWharton/timber/tree/trunk/timber-lint/src/main/java/timber/lint/WrongTimberUsageDetector.kt) Tests : [Source Code](https://github.com/JakeWharton/timber/tree/trunk/timber-lint/src/test/java/timber/lint/WrongTimberUsageDetectorTest.kt) Explicitly including the exception message is redundant when supplying an exception to log. !!! Tip This lint check has an associated quickfix available in the IDE. (##) Example Here is an example of lint warnings produced by this check: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text src/foo/Example.java:6:Warning: Explicitly logging exception message is redundant [TimberExceptionLogging] Timber.d(e.getMessage()); ------------------------ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here are the relevant source files: `src/foo/Example.java`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~java linenumbers package foo; import timber.log.Timber; public class Example { public void log() { Exception e = new Exception(); Timber.d(e.getMessage()); } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ `src/foo/Example.kt`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~kotlin linenumbers package foo import timber.log.Timber class Example { fun log() { val e = Exception() Timber.d(e.message) } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ You can also visit the [source code](https://github.com/JakeWharton/timber/tree/trunk/timber-lint/src/test/java/timber/lint/WrongTimberUsageDetectorTest.kt) for the unit tests for this check to see additional scenarios. The above example was automatically extracted from the first unit test found for this lint check, `WrongTimberUsageDetector.exceptionLoggingUsingExceptionMessage`. To report a problem with this extracted sample, visit https://github.com/JakeWharton/timber/issues. (##) Including !!! This is not a built-in check. To include it, add the below dependency to your project. This lint check is included in the lint documentation, but the Android team may or may not agree with its recommendations. ``` // build.gradle.kts implementation("com.jakewharton.timber:timber:5.0.1") // build.gradle implementation 'com.jakewharton.timber:timber:5.0.1' // build.gradle.kts with version catalogs: implementation(libs.timber) # libs.versions.toml [versions] timber = "5.0.1" [libraries] # For clarity and text wrapping purposes the following declaration is # shown split up across lines, but in TOML it needs to be on a single # line (see https://github.com/toml-lang/toml/issues/516) so adjust # when pasting into libs.versions.toml: timber = { module = "com.jakewharton.timber:timber", version.ref = "timber" } ``` 5.0.1 is the version this documentation was generated from; there may be newer versions available. [Additional details about com.jakewharton.timber:timber](com_jakewharton_timber_timber.md.html). (##) Suppressing You can suppress false positives using one of the following mechanisms: * Using a suppression annotation like this on the enclosing element: ```kt // Kotlin @Suppress("TimberExceptionLogging") fun method() { tag(...) } ``` or ```java // Java @SuppressWarnings("TimberExceptionLogging") void method() { tag(...); } ``` * Using a suppression comment like this on the line above: ```kt //noinspection TimberExceptionLogging problematicStatement() ``` * Using a special `lint.xml` file in the source tree which turns off the check in that folder and any sub folder. A simple file might look like this: ```xml <?xml version="1.0" encoding="UTF-8"?> <lint> <issue id="TimberExceptionLogging" severity="ignore" /> </lint> ``` Instead of `ignore` you can also change the severity here, for example from `error` to `warning`. You can find additional documentation on how to filter issues by path, regular expression and so on [here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html). * In Gradle projects, using the DSL syntax to configure lint. For example, you can use something like ```gradle lintOptions { disable 'TimberExceptionLogging' } ``` In Android projects this should be nested inside an `android { }` block. * For manual invocations of `lint`, using the `--ignore` flag: ``` $ lint --ignore TimberExceptionLogging ...` ``` * Last, but not least, using baselines, as discussed [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).