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SLF4J best practices

org.openrewrite.java.logging.slf4j.Slf4jBestPractices

Applies best practices to logging with SLF4J.

Tags​

  • slf4j
  • logging

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.

This recipe is available under the Moderne Source Available License.

Definition​

Examples​

Example 1​
Before​
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class Test {
    Logger logger = LoggerFactory.getLogger(String.class);
    void test() {
        Object obj1 = new Object();
        Object obj2 = new Object();
        logger.info("Hello " + obj1 + ", " + obj2);
        Exception e = new Exception();
        logger.warn(String.valueOf(e));
        logger.error(e.getMessage());
        logger.error(e.getLocalizedMessage());
    }
}
After​
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class Test {
    Logger logger = LoggerFactory.getLogger(Test.class);
    void test() {
        Object obj1 = new Object();
        Object obj2 = new Object();
        logger.info("Hello {}, {}", obj1, obj2);
        Exception e = new Exception();
        logger.warn("Exception", e);
        logger.error("", e);
        logger.error("", e);
    }
}
Example 2​
Before​
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class Test {
    Logger logger = LoggerFactory.getLogger(String.class);
    void test() {
        Object obj1 = new Object();
        Object obj2 = new Object();
        logger.info("Hello " + obj1 + ", " + obj2);
        Exception e = new Exception();
        logger.warn(String.valueOf(e));
        logger.error(e.getMessage());
        logger.error(e.getLocalizedMessage());
    }
}
After​
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class Test {
    Logger logger = LoggerFactory.getLogger(Test.class);
    void test() {
        Object obj1 = new Object();
        Object obj2 = new Object();
        logger.info("Hello {}, {}", obj1, obj2);
        Exception e = new Exception();
        logger.warn("Exception", e);
        logger.error("", e);
        logger.error("", e);
    }
}

Usage​

This recipe has no required configuration options. It can be activated by adding a dependency on org.openrewrite.recipe: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("7.6.2")
}

rewrite {
    activeRecipe("org.openrewrite.java.logging.slf4j.Slf4jBestPractices")
    setExportDatatables(true)
}

repositories {
    mavenCentral()
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-logging-frameworks:3.8.0")
}
  1. Run gradle rewriteRun to run the recipe.

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

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Please contact Moderne for more information about safely running the recipes on your own codebase in a private SaaS.

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.

Contributors​

Aaron Gershman, Tim te Beek, Sam Snyder, Knut Wannheden, Patrick, Kun Li, Md Riyazul Islam, Tim te Beek, Jonathan Schneider, Jonathan Schnéider, Andrii Rodionov, Adriano Machado, Peter Streef, Laurens Westerlaken, Johan Kragt, Joan Viladrosa, Greg Oledzki, Kevin McCarpenter