Unwanted output related to SLF4J

Question

Unwanted output related to SLF4J

wilyJ80 opened this issue 7 months ago · 1 comments

Description, Reproducing, Expected behavior, Logs, following:

(Sorry for the long text, I just want to document this for people who might have the same problem, also, I'm a beginner in the way of the Maven, so have patience 😭)

I'm making a simple SQLite CLI app. All I wanted was to bundle the whole SQLite app into a fat jar using Maven, so this should be simple, right? Right?

Since I wanted to use Maven, I avoided manually downloading the jars, as instructed by the README, and tried to add the Maven plugin for sqlite-jdbc, of course, as well as the other Maven configurations described (the hint for maven-shade-plugin). There's nothing special in the following pom.xml, it's just the default Maven archetype with the necessary adjustments I wanted.

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>sqlite</groupId>
  <artifactId>sqlite</artifactId>
  <version>1.0-SNAPSHOT</version>

  <name>sqlite</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>17</maven.compiler.source>
    <maven.compiler.target>17</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.xerial</groupId>
      <artifactId>sqlite-jdbc</artifactId>
      <version>3.45.3.0</version>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>3.5.3</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <transformers>
                <transformer
                  implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                  <mainClass>sqlite.App</mainClass>
                </transformer>
                <transformer
                  implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                  <resource>META-INF/services/java.sql.Driver</resource>
                </transformer>
              </transformers>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to
      parent pom) -->
      <plugins>
        <!-- clean lifecycle, see
        https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- default lifecycle, jar packaging: see
        https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-jar-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
        <!-- site lifecycle, see
        https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
        <plugin>
          <artifactId>maven-site-plugin</artifactId>
          <version>3.7.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-project-info-reports-plugin</artifactId>
          <version>3.0.0</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

Trying to run it after creating the fat jar with mvn clean package:

[victor@victor-82mf sqlite]$ java -jar target/sqlite-1.0-SNAPSHOT.jar 
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Connection to SQLite has been established.

Well, this seems to work OK, since the point of the app is simply to test the connection. But I sure as heck don't want that unwanted warnings in my CLI app output, sorry. So let's try something else: the logical next step is adding the sl4j-api dependency to my pom.xml. I hope it works... and yes, I read the issue where it's described the version of slf4j is an older version, so I made the following adjustment with that in mind:

    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>1.7.36</version>
    </dependency>

Same unwanted logging:

[victor@victor-82mf sqlite]$ java -jar target/sqlite-1.0-SNAPSHOT.jar 
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Connection to SQLite has been established.

Some digging on StackOverflow instructed adding the slf4j-nop plugin to my pom. Let's be careful and add the same version as the slf4j-api plugin. Well, here we go:

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-nop</artifactId>
    <version>1.7.36</version>
    <scope>test</scope>
</dependency>

Same errors.
What to do? Thank you for any help, by the way.

Environment (please complete the following information):

OS: EndeavourOS
CPU architecture: x86_64
sqlite-jdbc version 3.45.3.0

Answer 1 · 2024-05-13T01:53:55.000Z

you need to include an implementation of slf4j like slf4j-simple or logback