JavaPlugin cannot be resolved to a type-CodePudding

I want to code a 1.18.2 Minecraft plugin using Java in the eclipse IDE. I'm pretty sure I'm using the latest versions for everything. I'm using a tutorial and when it said to put this in:

public class Main extends JavaPlugin {

A red line shows up under JavaPlugin and it says it cannot be resolved to a type. I'm supposed to import this:

import org.bukkit.plugin.java.JavaPlugin;

Everything I've googled has said to put the spigot jar in project properties > build path > libraries > add external jar which I've done, but it still doesn't work.

CodePudding user response：

It's better to use platform like maven or gradle. Since Spigot 1.17 (include) it's not so easy to use spigot build as build path library.

You should :

Convert your project into a maven/gradle one. Here you own are empty, so maybe it's easier for you to remove it and create a new project which is not basic but maven/gradle one.

You can also do it with right click on project -> Configure -> Choose what you want

In dependency, add:

Maven (documentation):

<repositories>
    <!-- This adds the Spigot Maven repository to the build -->
    <repository>
        <id>spigot-repo</id>
        <url>https://hub.spigotmc.org/nexus/content/repositories/snapshots/</url>
    </repository>
</repositories>

<dependencies>
    <!--This adds the Spigot API artifact to the build -->
    <dependency>
           <groupId>org.spigotmc</groupId>
           <artifactId>spigot-api</artifactId>
           <version>1.18.2-R0.1-SNAPSHOT</version>
           <scope>provided</scope>
    </dependency>
</dependencies>

Gradle (documentation):

repositories {
   maven { url = 'https://oss.sonatype.org/content/repositories/snapshots' }
}
dependencies {
  // Pick only one of these and read the comment in the repositories block.
  compileOnly 'org.spigotmc:spigot-api:1.18.2-R0.1-SNAPSHOT'
}

Refresh your project. It will automatically download dependencies and build your project.
To generate your jar for your plugin, you should :

Maven: right click on project -> Run As -> Maven build

Gradle: You should create a new task (on top, where you run basic Java project) and config it as you want. More informations