main class not found

[Angus Ferguson]

Hi all,

I have attached a project the error I get is:

Error: the main class has been nor loaded or founded com.example.demo.DemoApplication

The zip file is at Google Drive : https://drive.google.com/drive/folders/1Xu6RihW_CIPQEXnshYqS2K_wKB8Iyj5k?usp=sharing

Any idea, please?

Regards, Isaac

[Carey Brown]

I'm not going to download and unzip your file. Please post the code for the class containing main(). If it's too long then trim it so it only leaves the main() method.

[Norm Radder]

Also can you copy the contents of the command prompt window from when you tried to execute the program and paste it here.


I assume the error message you posted was fromwhen you tried to execute the program.

Otherwise please explain where that error message came from.

[Angus Ferguson]

<?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>com.example</groupId>
	<artifactId>demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>demo</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.1.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-security</artifactId>
		</dependency>
		
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.security</groupId>
			<artifactId>spring-security-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId> // When mouseover : The managed version is 2.0.1.RELEASE The artifact is managed in org.springframework.boot:spring-boot-starter-parent:[unknown-version]
			</plugin>
		</plugins>
	</build>

</project>

I refreshed, and updated project.

package com.example.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);
	}
}

This is the error :

Error: no se ha encontrado o cargado la clase principal com.example.demo.DemoApplication

Error: main class it is not found or loaded com.example.demo.DemoApplication

Any idea, please?

Regards, Isaac

[Paweł Baczyński]

How are you running this program?

[Angus Ferguson]

Using Spring Boot-> Run as Spring Boot app

[Lakshman Arun]

Is your project built and the class file named DemoApplication.class created.

[Angus Ferguson]

In fact it is not generating any .class file

[Campbell Ritchie]

Can you compile it from the command line? Are you getting any error messages?

[Angus Ferguson]

When I try to export the .jar and run it in the console, I get this exporting error:

JAR creation failed. See details for additional information.
  Class files on classpath not found or not accessible for: 'demo/src/main/java/com/example/demo/DemoApplication.java'
  duplicate entry: notice.txt
  duplicate entry: notice.txt
  duplicate entry: changelog.txt
  duplicate entry: changelog.txt
  duplicate entry: readme.txt
  duplicate entry: readme.txt
  duplicate entry: license.txt
  duplicate entry: license.txt

I made a clean with Maven, and  I did right click on repo, chose build path->Conifgure build->Project References and checked the project references for my repo.

Any idea, please?