The editor cannot recognize the intellisense or the library

I'm using IntelliJ and when I start a project from Maven artifact generation, I can compile it as a Maven task, let alone intellisense, but the editor doesn't recognize it. I was worried quite a bit, but I solved this with a hint

IntelliJ not able to resolve classes of external Libraries for Maven projects

After all,

Project right click> Maven> ReImport

Solved with. (I don't know that)

By the way, when I was investigating before that, I set the source directory and the test directory, though it doesn't matter. The location can be set by selecting the project and going to File> Project Settings> Modules> Source.

But it's probably solved by ReImport.

Slf4j error when running Kafka Client in IntelliJ

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.

Damn addicted. Looking at the URL above, it says it's a good idea to add the library to pom.xml. Blogs and Stack Overflow say so, but I couldn't solve it at all. However, he was healed without knowing it. Probably, the setting that added the library should be valid, but it seems that I was looking at the old one, but now I do not know the cause.

   <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>1.7.25</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-jdk14</artifactId>
      <version>1.7.25</version>
    </dependency>

Even if I added the above to pom.xml and tried clear, install, compile, it did not heal, so I tried to check it manually, I put the following plug-in, I was confused, and I ran it from IntelliJ after a long time I don't know what it means, but it worked.

        <plugin>
          <groupId>org.codehaus.mojo</groupId>
          <artifactId>exec-maven-plugin</artifactId>
          <version>1.2.1</version>
          <configuration>
            <mainClass>simplearchitect.App</mainClass>
          </configuration>
        </plugin>

This is probably because I don't understand how IntelliJ behaves. This library is a plugin that runs the app manually, referring to Maven's Dependency, not from IntelliJ. Works with mvn exec: java. It worked fine here.

By the way, to know the version of the target library

mvn dependency:tree

Alternatively, check the IntelliJ maven panel.

Error: java: javacTask:source release 8 requires target release 1.8

This is because the template generated by artifact was 1.7. Rewrite pom.xml.

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>

However, this is not enough, and the above ReImport is required. The Target bytecode version of the Preference> Build, Execution, Deployment> Compiler> Java Compiler project is still out of date.

Note not to forget

Problems when starting IntelliJ from Maven artifact

The editor cannot recognize the intellisense or the library

Slf4j error when running Kafka Client in IntelliJ