Why doesn't the Java code run?

Question

Java

Hey guys.
I have a finished project - not written by me, but I need to redo it a bit.
I've never dealt with Java before. I downloaded Java, JDK, JDE and everything))
IDE - Eclipse
I imported this project there and try to save it, but it gives such an error

Despite the fact that main is and is described

package edu.lp.ippt.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class DemoApplication {

  public static void main(String[] args) {
    SpringApplication.run(DemoApplication.class, args);
  }
}

Answer 1

The project is made using the Gradle build system.
You need to install and configure gradle.
And at the beginning try to collect them.
Only then try to import into Eclipse.
IMHO, Eclipse is not the most convenient IDE to start with, it makes sense to look towards NetBeans