Java – error R10 (boot timeout) – > the web process cannot bind to $port – heroku within 60 seconds after startup

I'm trying to deploy my server on heroku I received this error:

Error R10 (Boot timeout) -> Web process Failed to bind to $PORT within 60 seconds of launch

This is my java class:

package introsde.document.endpoint;
import javax.xml.ws.Endpoint;

import introsde.assignment.soap.PeopleImpl;

public class PeoplePublisher {
public static String SERVER_URL = "http://localhost";
public static String PORT = "6902";
public static String BASE_URL = "/ws/people";

public static String getEndpointURL() {
    return SERVER_URL+":"+PORT+BASE_URL;
}

public static void main(String[] args) {
    String endpointUrl = getEndpointURL();
    System.out.println("Starting People Service...");
    System.out.println("--> Published at = "+endpointUrl);
    Endpoint.publish(endpointUrl,new PeopleImpl());
}
}

How can I solve this problem?

thank you

Solution

The same problem was encountered when trying to create a minimal spring boot application I've compared heroku's Java - getting - started implementation with mine and found a good fix

server.port=${PORT:5000}