SendGrid emails in Spring Boot

implementation 'com.sendgrid:sendgrid-java:4.6.1'

# SENDGRID CONFIG (SendGridAutoConfiguration)
spring.sendgrid.api-key: <API-KEY> # SendGrid API Key

spring.sendgrid.username: # SendGrid account username (if API key not provided).
spring.sendgrid.password: # SendGrid account password.

pring.sendgrid.proxy.host: # SendGrid proxy host. (optional)
spring.sendgrid.proxy.port: # SendGrid proxy port. (optional)

import com.sendgrid.Method;
import com.sendgrid.Request;
import com.sendgrid.Response;
import com.sendgrid.SendGridAPI;
import com.sendgrid.helpers.mail.Mail;
import com.sendgrid.helpers.mail.objects.Content;
import com.sendgrid.helpers.mail.objects.Email;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.stereotype.Component;

import java.io.IOException;

@Component
public class SendGridMailer {

    @Autowired
    private SendGridAPI sendGridAPI;

    void sendMail() {
        Email from = new Email("from@example.com", "Foo Bar");
        String subject = "Test email with SendGrid";
        Email to = new Email("to@example.com");
        Content content = new Content("text/plain", "Test email with Spring");
        Mail mail = new Mail(from, subject, to, content);
        Request request = new Request();
        try {
            request.setMethod(Method.POST);
            request.setEndpoint("mail/send");
            request.setBody(mail.build());
            Response response = sendGridAPI.api(request);
            System.out.println(response.getBody());
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

// using SendGrid's Java Library
// https://github.com/sendgrid/sendgrid-java

import com.sendgrid.*;

import java.io.IOException;

public class Example {

    public static void main(String[] args) throws IOException {
        Email from = new Email("test@example.com");
        String subject = "Sending with SendGrid is Fun";
        Email to = new Email("test@example.com");
        Content content = new Content("text/plain", "and easy to do anywhere, even with Java");
        Mail mail = new Mail(from, subject, to, content);
        SendGrid sg = new SendGrid(System.getenv("SENDGRID_API_KEY"));
        Request request = new Request();
        try {
            request.setMethod(Method.POST);
            request.setEndpoint("mail/send");
            request.setBody(mail.build());
            Response response = sg.api(request);
            System.out.println(response.getStatusCode());
            System.out.println(response.getBody());
            System.out.println(response.getHeaders());
        } catch (IOException ex) {
            throw ex;
        }
    }
}