JavaEventClassesGenerator.java

/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * Licensed 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.kaaproject.kaa.server.control.service.sdk.event;

import org.kaaproject.kaa.common.dto.event.ApplicationEventAction;
import org.kaaproject.kaa.common.dto.event.ApplicationEventMapDto;
import org.kaaproject.kaa.server.control.service.sdk.SdkGenerator;
import org.kaaproject.kaa.server.control.service.sdk.compiler.JavaDynamicBean;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class JavaEventClassesGenerator {


  private static final Logger LOG = LoggerFactory.getLogger(JavaEventClassesGenerator.class);

  private static final String FOLDER = "sdk/java/event/";

  private static final String EVENT_FAMILY_FACTORY = "EventFamilyFactory";


  private static final String EVENT_FAMILY_JAVA_TEMPLATE = FOLDER + "EventFamily.java.template";

  private static final String EVENT_FAMILY_FACTORY_JAVA_TEMPLATE = FOLDER
      + "EventFamilyFactory.java.template";

  private static final String EVENT_FAMILY_ADD_SUPPORTED_FQN_TEMPLATE = FOLDER
      + "eventFamilyAddSupportedFqn.template";


  private static final String EVENT_FAMILY_ON_GENERIC_EVENT_TEMPLATE =  FOLDER
      + "eventFamilyOnGenericEvent.template";


  private static final String EVENT_FAMILY_SEND_EVENT_METHODS_TEMPLATE = FOLDER
      + "eventFamilySendEventMethods.template";


  private static final String EVENT_FAMILY_LISTENER_METHOD_TEMPLATE = FOLDER
      + "eventFamilyListenerMethod.template";


  private static final String EVENT_FAMILY_FACTORY_METHOD_TEMPLATE =  FOLDER
      + "eventFamilyFactoryMethod.template";



  private static final String EVENT_FAMILY_NAMESPACE_VAR = "\\$\\{event_family_namespace\\}";
  private static final String EVENT_FAMILY_CLASS_NAME_VAR = "\\$\\{event_family_class_name\\}";
  private static final String EVENT_FAMILY_VAR_NAME_VAR = "\\$\\{event_family_var_name\\}";

  private static final String ADD_SUPPORTED_EVENT_CLASS_FQNS_VAR =
      "\\$\\{add_supported_event_class_fqns\\}";

  private static final String EVENT_FAMILY_LISTENERS_ON_GENERIC_EVENT_VAR =
      "\\$\\{event_family_listeners_on_generic_event\\}";

  private static final String EVENT_FAMILY_SEND_EVENT_METHODS_VAR =
      "\\$\\{event_family_send_event_methods\\}";

  private static final String EVENT_FAMILY_LISTENER_METHODS_VAR =
      "\\$\\{event_family_listener_methods\\}";

  private static final String EVENT_CLASS_FQN_VAR = "\\$\\{event_class_fqn\\}";

  private static final String EVENT_FAMILY_FACTORY_IMPORTS_VAR =
      "\\$\\{event_family_factory_imports\\}";

  private static final String EVENT_FAMILY_FACTORY_METHODS_VAR =
      "\\$\\{event_family_factory_methods\\}";



  private static String eventFamilyJava;
  private static String eventFamilyAddSupportedFqn;
  private static String eventFamilyOnGenericEvent;
  private static String eventFamilySendEventMethod;
  private static String eventFamilyListenerMethod;
  private static String eventFamilyFactoryJava;
  private static String eventFamilyFactoryMethod;

  static {
    try {
      eventFamilyJava = SdkGenerator.readResource(EVENT_FAMILY_JAVA_TEMPLATE);

      eventFamilyAddSupportedFqn = SdkGenerator
          .readResource(EVENT_FAMILY_ADD_SUPPORTED_FQN_TEMPLATE);

      eventFamilyOnGenericEvent = SdkGenerator
          .readResource(EVENT_FAMILY_ON_GENERIC_EVENT_TEMPLATE);

      eventFamilySendEventMethod = SdkGenerator
          .readResource(EVENT_FAMILY_SEND_EVENT_METHODS_TEMPLATE);

      eventFamilyListenerMethod = SdkGenerator.readResource(EVENT_FAMILY_LISTENER_METHOD_TEMPLATE);
      eventFamilyFactoryJava = SdkGenerator.readResource(EVENT_FAMILY_FACTORY_JAVA_TEMPLATE);
      eventFamilyFactoryMethod = SdkGenerator.readResource(EVENT_FAMILY_FACTORY_METHOD_TEMPLATE);
    } catch (IOException ex) {
      LOG.error("Unable to initialize JavaEventClassesGenerator", ex);
    }
  }

  private JavaEventClassesGenerator() {
  }

  /**
   * Generate event classes for event family metadata.
   *
   * @param eventFamilies the event family metadata
   * @return the list of event classes
   */
  public static List<JavaDynamicBean> generateEventClasses(
      List<EventFamilyMetadata> eventFamilies) {

    List<JavaDynamicBean> javaSources = new ArrayList<>();

    String eventFamilyFactoryImports = "";
    String eventFamilyFactoryMethods = "";

    for (EventFamilyMetadata efm : eventFamilies) {
      eventFamilyFactoryImports += "import "
          + efm.getEcfNamespace()
          + "."
          + efm.getEcfClassName() + ";\n";

      String eventFamilyVarName = efm.getEcfClassName().substring(0, 1).toLowerCase();
      if (efm.getEcfClassName().length() > 1) {
        eventFamilyVarName += efm.getEcfClassName().substring(1);
      }
      eventFamilyFactoryMethods += eventFamilyFactoryMethod
          .replaceAll(EVENT_FAMILY_CLASS_NAME_VAR, efm.getEcfClassName())
          .replaceAll(EVENT_FAMILY_VAR_NAME_VAR, eventFamilyVarName);

      String addSupportedEventClassFqns = "";
      String eventFamilyListenersOnGenericEvent = "";
      String eventFamilySendEventMethods = "";
      String eventFamilyListenerMethods = "";

      for (ApplicationEventMapDto eventMap : efm.getEventMaps()) {
        if (eventMap.getAction() == ApplicationEventAction.SINK
            || eventMap.getAction() == ApplicationEventAction.BOTH) {
          addSupportedEventClassFqns += eventFamilyAddSupportedFqn
              .replaceAll(EVENT_CLASS_FQN_VAR, eventMap.getFqn()) + "\n";
          if (eventFamilyListenersOnGenericEvent.length() > 0) {
            eventFamilyListenersOnGenericEvent += "else ";
          }
          eventFamilyListenersOnGenericEvent += eventFamilyOnGenericEvent
              .replaceAll(EVENT_CLASS_FQN_VAR, eventMap.getFqn()) + "\n";
          eventFamilyListenerMethods += eventFamilyListenerMethod
              .replaceAll(EVENT_CLASS_FQN_VAR, eventMap.getFqn()) + "\n";
        }
        if (eventMap.getAction() == ApplicationEventAction.SOURCE
            || eventMap.getAction() == ApplicationEventAction.BOTH) {
          eventFamilySendEventMethods += eventFamilySendEventMethod
              .replaceAll(EVENT_CLASS_FQN_VAR, eventMap.getFqn()) + "\n";
        }
      }

      String eventFamilySource = eventFamilyJava
          .replaceAll(EVENT_FAMILY_NAMESPACE_VAR, efm.getEcfNamespace())
          .replaceAll(EVENT_FAMILY_CLASS_NAME_VAR, efm.getEcfClassName())
          .replaceAll(ADD_SUPPORTED_EVENT_CLASS_FQNS_VAR, addSupportedEventClassFqns)
          .replaceAll(
              EVENT_FAMILY_LISTENERS_ON_GENERIC_EVENT_VAR,
              eventFamilyListenersOnGenericEvent
          )
          .replaceAll(EVENT_FAMILY_SEND_EVENT_METHODS_VAR, eventFamilySendEventMethods)
          .replaceAll(EVENT_FAMILY_LISTENER_METHODS_VAR, eventFamilyListenerMethods);

      LOG.trace("Going to compile {} using source {}", efm.getEcfClassName(), eventFamilySource);

      JavaDynamicBean eventFamily = new JavaDynamicBean(efm.getEcfClassName(), eventFamilySource);

      javaSources.add(eventFamily);
    }

    String eventFamilyFactorySource = eventFamilyFactoryJava
        .replaceAll(EVENT_FAMILY_FACTORY_IMPORTS_VAR, eventFamilyFactoryImports)
        .replaceAll(EVENT_FAMILY_FACTORY_METHODS_VAR, eventFamilyFactoryMethods);


    LOG.trace("Going to compile {} using source {}",
            EVENT_FAMILY_FACTORY, eventFamilyFactorySource);
    JavaDynamicBean eventFamilyFactory = new JavaDynamicBean(
            EVENT_FAMILY_FACTORY, eventFamilyFactorySource);
    javaSources.add(eventFamilyFactory);

    return javaSources;
  }

}