content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.applib.services.email;
  
  import java.io.Serializable;
  import java.util.List;
  
  import jakarta.activation.DataSource;
  import jakarta.annotation.PostConstruct;
  
  /**
   *
   * The `EmailService` provides the ability to send HTML emails, with
   * attachments, to one or more recipients.
   *
   * <p>
   *     The framework provides a default implementation to send emails using
   *     an external SMTP provider.
   * </p>
   *
   * @since 1.x {@index}
   */
  public interface EmailService extends Serializable {
  
      @PostConstruct
      public void init() ;
  
      /**
       * The main API to send the email (and optional attachments).
       *
       * @param to - pass either `null` or `Collections.emptyList()` if not required
       * @param cc - pass either `null` or `Collections.emptyList()` if not required
       * @param bcc - pass either `null` or `Collections.emptyList()` if not required
       * @param subject - a simple string, no formatting
       * @param body - should be HTML text
       * @param attachments - attachments that describe their mime type
       *
       * @return Will return `false` if failed to send
       */
      boolean send(List<String> to, List<String> cc, List<String> bcc, String subject, String body, DataSource... attachments);
  
      /**
       * Whether this service has been configured and thus available for use.
       *
       * @return if `false` then any attempt to call `send(...)` will throw an exception.
       */
      boolean isConfigured();
  
  }
  