org.camunda.bpm.engine.impl.history.handler.CompositeHistoryEventHandler Maven / Gradle / Ivy
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* Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
* under one or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information regarding copyright
* ownership. Camunda licenses this file to you under the Apache License,
* Version 2.0; 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.camunda.bpm.engine.impl.history.handler;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.camunda.bpm.engine.impl.history.event.HistoryEvent;
import org.camunda.bpm.engine.impl.util.EnsureUtil;
/**
* A {@link HistoryEventHandler} implementation which delegates to a list of
* {@link HistoryEventHandler}.
*
* @author Alexander Tyatenkov
*
*/
public class CompositeHistoryEventHandler implements HistoryEventHandler {
/**
* The list of {@link HistoryEventHandler} which consume the event.
*/
protected final List historyEventHandlers = new ArrayList<>();
/**
* Non-argument constructor for default initialization.
*/
public CompositeHistoryEventHandler() {
}
/**
* Constructor that takes a varargs parameter {@link HistoryEventHandler} that
* consume the event.
*
* @param historyEventHandlers
* the list of {@link HistoryEventHandler} that consume the event.
*/
public CompositeHistoryEventHandler(final HistoryEventHandler... historyEventHandlers) {
initializeHistoryEventHandlers(Arrays.asList(historyEventHandlers));
}
/**
* Constructor that takes a list of {@link HistoryEventHandler} that consume
* the event.
*
* @param historyEventHandlers
* the list of {@link HistoryEventHandler} that consume the event.
*/
public CompositeHistoryEventHandler(final List historyEventHandlers) {
initializeHistoryEventHandlers(historyEventHandlers);
}
/**
* Initialize {@link #historyEventHandlers} with data transfered from constructor
*
* @param historyEventHandlers
*/
private void initializeHistoryEventHandlers(final List historyEventHandlers) {
EnsureUtil.ensureNotNull("History event handler", historyEventHandlers);
for (HistoryEventHandler historyEventHandler : historyEventHandlers) {
EnsureUtil.ensureNotNull("History event handler", historyEventHandler);
this.historyEventHandlers.add(historyEventHandler);
}
}
/**
* Adds the {@link HistoryEventHandler} to the list of
* {@link HistoryEventHandler} that consume the event.
*
* @param historyEventHandler
* the {@link HistoryEventHandler} that consume the event.
*/
public void add(final HistoryEventHandler historyEventHandler) {
EnsureUtil.ensureNotNull("History event handler", historyEventHandler);
historyEventHandlers.add(historyEventHandler);
}
@Override
public void handleEvent(final HistoryEvent historyEvent) {
for (HistoryEventHandler historyEventHandler : historyEventHandlers) {
historyEventHandler.handleEvent(historyEvent);
}
}
@Override
public void handleEvents(final List historyEvents) {
for (HistoryEvent historyEvent : historyEvents) {
handleEvent(historyEvent);
}
}
}