Spring @Service logic with Builder Pattern

I have implemented service logic using builder pattern like below in a Spring boot application.

 @Service
public class EmailServiceImpl implements NotificationService{
private Map<String, Object> emailTemplateContext;;
private List<String> recipients;
private String templateName;
private String subjectName;
private List<String> ccRecipients;
public EmailServiceImpl() {
}
private EmailServiceImpl(String templateName, String subjectName, List<String> recipients,
List<String> ccRecipients,
Map<String, Object> emailTemplateContext) {
this.emailTemplateContext = emailTemplateContext;
this.recipients = recipients;
this.templateName = templateName;
this.subjectName = subjectName;
this.ccRecipients = ccRecipients;
}
public static class EmailBuilder {
private Map<String, Object> emailTemplateContext = new HashMap<String, Object>();
private List<String> recipients;
private String templateName;
private String subjectName;
private List<String> ccRecipients;
public EmailBuilder withTemplateName(String templateName) {
this.templateName = templateName;
return this;
}
public EmailBuilder withSubjectName(String subjectName) {
this.subjectName = subjectName;
return this;
}
public EmailBuilder withTemplateContextValues(String key, String value) {
this.emailTemplateContext.put(key, value);
return this;
}
public EmailBuilder withTemplateContextValues(String key,List< String> value) {
this.emailTemplateContext.put(key, value);
return this;
}
public EmailBuilder withRecipients(List<String> recipients) {
this.recipients = recipients;
return this;
}
public EmailBuilder withCCRecipients(List<String> ccRecipients) {
this.ccRecipients = ccRecipients;
return this;
}
public EmailServiceImpl build() {
return new EmailServiceImpl(templateName, subjectName, recipients, ccRecipients, emailTemplateContext);
}
}
public void send() {
// implement email send logic
}
}

Then this will be injected in another class something like below

 public class EmailSender{
private EmailBuilder emailBuilder;
EmailSender(EmailBuilder emailBuilder){
this.emailBuilder=emailBuilder;
}
public void sendEmail(){
this.emailBuilder
.withRecipients(executionRunBO.getEmailRecipients().stream().map(email -> email.getEmail())
.collect(Collectors.toList()))
.withSubjectName("Reports Draft ").withTemplateName("/emails/reports.ftlh")
.withTemplateContextValues("userName", "TestUser").build().send();
}
}

There are few questions related to the Builder pattern with Spring.

1. Since @service constructor is private Spring framework can not initiate the bean class.To avoid getting initialization exception i have made constructor to public but it is not the builder pattern.So how do i implement builder pattern correctly with Spring framework?

2. How do i call the EmailServiceImpl class's EmailBuilder outside from the service class? Since in my examples i have injected EmailBuilder as a constructor argument then Spring framework throws that

> required a bean of type '...EmailServiceImpl$EmailBuilder' that could
> not be found.

Please help me to clarify those things.

You are mixing a lot of functionality together here. I would make this more streamlined.

I would create a dto class Email, not a Spring bean.

public class Email {
private Map<String, Object> emailTemplateContext;
private List<String> recipients;
private String templateName;
private String subjectName;
private List<String> ccRecipients;
private Email(String templateName, String subjectName, List<String> recipients,
List<String> ccRecipients,
Map<String, Object> emailTemplateContext) {
this.emailTemplateContext = emailTemplateContext;
this.recipients = recipients;
this.templateName = templateName;
this.subjectName = subjectName;
this.ccRecipients = ccRecipients;
}
public static class EmailBuilder {
// your builder code, just build the Email 
}
}

And then have a service to send emails.

@Service
public class EmailServiceImpl implements NotificationService {
public void sendEmail(Email email) {
}
}

Call it like this

emailService.sendEmail(new Email.EmailBuilder().build());

There is no need to create a @service from the Email and EmailBuilder.