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Migrate Log4j to SLF4J

org.openrewrite.java.logging.slf4j.Log4jToSlf4j

Migrates usage of Apache Log4j to using SLF4J directly. Use of the traditional Log4j to SLF4J bridge can result in loss of performance, as the Log4j messages must be formatted before they can be passed to SLF4J. Note, this currently does not modify log4j.properties files.

Tags​

  • slf4j
  • logging
  • log4j

Recipe source​

GitHub, Issue Tracker, Maven Central

info

This recipe is composed of more than one recipe. If you want to customize the set of recipes this is composed of, you can find and copy the GitHub source for the recipe from the link above.

Definition​

Usage​

This recipe has no required configuration options. It can be activated by adding a dependency on org.openrewrite.recipe:rewrite-logging-frameworks:{{VERSION_REWRITE_LOGGING_FRAMEWORKS}} in your build file or by running a shell command (in which case no build changes are needed):

  1. Add the following to your build.gradle file:
build.gradle
plugins {
    id("org.openrewrite.rewrite") version("6.28.1")
}

rewrite {
    activeRecipe("org.openrewrite.java.logging.slf4j.Log4jToSlf4j")
    setExportDatatables(true)
}

repositories {
    mavenCentral()
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-logging-frameworks:2.17.1")
}
  1. Run gradle rewriteRun to run the recipe.

See how this recipe works across multiple open-source repositories​

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Data Tables​

Source files that had results​

org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

Column NameDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.

Source files that errored on a recipe​

org.openrewrite.table.SourcesFileErrors

The details of all errors produced by a recipe run.

Column NameDescription
Source pathThe file that failed to parse.
Recipe that made changesThe specific recipe that made a change.
Stack traceThe stack trace of the failure.

Recipe performance​

org.openrewrite.table.RecipeRunStats

Statistics used in analyzing the performance of recipes.

Column NameDescription
The recipeThe recipe whose stats are being measured both individually and cumulatively.
Source file countThe number of source files the recipe ran over.
Source file changed countThe number of source files which were changed in the recipe run. Includes files created, deleted, and edited.
Cumulative scanning timeThe total time spent across the scanning phase of this recipe.
99th percentile scanning time99 out of 100 scans completed in this amount of time.
Max scanning timeThe max time scanning any one source file.
Cumulative edit timeThe total time spent across the editing phase of this recipe.
99th percentile edit time99 out of 100 edits completed in this amount of time.
Max edit timeThe max time editing any one source file.

Contributors​

Aaron Gershman, Patrick, Sam Snyder, Md Riyazul Islam, Knut Wannheden, Tim te Beek, Jonathan Schnéider, Adriano Machado, Tim te Beek, Kun Li, Peter Streef