AlarmHistory.java
/*
* Copyright 1996-2011 Niclas Hedhman.
*
* 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.qi4j.library.alarm;
import java.util.List;
import java.util.Map;
import org.qi4j.api.common.UseDefaults;
import org.qi4j.api.mixin.Mixins;
import org.qi4j.api.property.Property;
/**
* History of an AlarmPoint.
* AlarmPoint system <i>should</i> implement <code>AlarmHistory</code> classes to
* record the events of an <code>AlarmPoint</code>.
*
*/
@Mixins( AlarmHistory.AlarmHistoryMixin.class )
public interface AlarmHistory
{
/**
* Returns the newest recorded <code>AlarmEvent</code>.
*
* @return the last AlarmEvent in the buffer. This is the newest event.
*/
AlarmEvent lastEvent();
/**
* Returns the oldest recorded <code>AlarmEvent</code>.
*
* @return the first AlarmEvent in the buffer. This is the oldest event.
*/
AlarmEvent firstEvent();
/**
* Returns the recorded <code>AlarmEvent</code> at the given position
* in the buffer.
*
* @param position the position in the buffer, counted from the beginning to obtain the AlarmEvent from.
* 0 means the first element.
*
* @return the recorded <code>AlarmEvent</code> at the given position in the buffer.
*/
AlarmEvent eventAt( int position );
/**
* Returns the recorded <code>AlarmEvent</code> at the given position
* in the buffer counted from the end.
*
* @param position the position in the buffer, counted from the end to obtain the AlarmEvent from.
* 0 means the last element.
*
* @return the recorded <code>AlarmEvent</code> at the given position in the buffer counted from the end.
*/
AlarmEvent eventAtEnd( int position );
/**
* Returns a <code>java.util.List</code> of all recorded <code>AlarmEvents</code>.
*
* @return a <code>java.util.List</code> of all recorded <code>AlarmEvents</code>.
*/
@UseDefaults
Property<List<AlarmEvent>> allAlarmEvents();
/**
* The maximum size of the history buffer.
* If the sizes shrinks, the oldest <code>AlarmEvents</code> should be removed
* so that the number of stored events are equal to the new <i>MaxSize</i>.
*
* @return The maxSize Property instance.
*/
@UseDefaults
Property<Integer> maxSize();
/**
* Returns all the Counters of triggers.
* Each time the <code>trigger()</code> method is called,
* a Counter is incremented. That means that after the first
* time the following the sequence is called
* <pre>
* <code>activate();
* acknowledge();
* deactivate();
* </code></pre>, the Map contains
* <table summary="Triggers">
* <tr><td>(String) activate</td><td>(Integer) 1</td></tr>
* <tr><td>(String) deactivate</td><td>(Integer) 1</td></tr>
* <tr><td>(String) acknowledge</td><td>(Integer) 1</td></tr>
* </table>
*
* @return all the Counters of triggers.
*/
@UseDefaults
Property<Map<String, Integer>> counters();
/**
* Resets all counters.
*/
void resetAllCounters();
/**
* Returns the Counter of activate triggers.
* This method will return the number of times the
* <code>activate()</code> method and the <code>trigger()</code>
* method with an activate trigger is called.
*
* @return the Counter of activate triggers.
*/
int activateCounter();
/**
* Resets the Activate counter.
*/
void resetActivateCounter();
void addEvent( AlarmEvent event, String trigger );
abstract class AlarmHistoryMixin
implements AlarmHistory
{
@Override
public AlarmEvent firstEvent()
{
List<AlarmEvent> eventList = allAlarmEvents().get();
if( eventList.isEmpty() )
{
return null;
}
return eventList.get( 0 );
}
@Override
public AlarmEvent lastEvent()
{
List<AlarmEvent> eventList = allAlarmEvents().get();
if( eventList.isEmpty() )
{
return null;
}
return eventList.get( eventList.size() - 1 );
}
@Override
public AlarmEvent eventAt( final int position )
{
List<AlarmEvent> eventList = allAlarmEvents().get();
if( eventList.size() <= position || position < 0 )
{
return null;
}
return eventList.get( position );
}
@Override
public AlarmEvent eventAtEnd( final int position )
{
List<AlarmEvent> eventList = allAlarmEvents().get();
int size = eventList.size();
if( size <= position || position < 0 )
{
return null;
}
return eventList.get( size - position - 1 );
}
@Override
public void addEvent( AlarmEvent event, String trigger )
{
List<AlarmEvent> eventList = allAlarmEvents().get();
eventList.add( event );
purge();
allAlarmEvents().set( eventList );
Map<String, Integer> counters = counters().get();
Integer counter = counters.get( trigger );
if( counter == null )
{
counter = 1;
}
else
{
counter = counter + 1;
}
counters.put( trigger, counter );
counters().set( counters );
}
@Override
public String toString()
{
StringBuilder buf = new StringBuilder();
buf.append( "history[maxsize=" );
buf.append( maxSize().get() );
buf.append( ", size=" );
buf.append( allAlarmEvents().get().size() );
for( Map.Entry<String, Integer> entry : counters().get().entrySet() )
{
String type = entry.getKey();
Integer counts = entry.getValue();
buf.append( ", " );
buf.append( type );
buf.append( "=" );
buf.append( counts );
}
buf.append( "]" );
return buf.toString();
}
private void purge()
{
List<AlarmEvent> eventList = allAlarmEvents().get();
Integer maxSize = maxSize().get();
if( maxSize <= 0 )
{
eventList.clear();
}
while( eventList.size() > maxSize )
{
eventList.remove( 0 );
}
}
@Override
public void resetAllCounters()
{
Map<String, Integer> counters = counters().get();
counters.clear();
counters().set(counters);
}
@Override
public int activateCounter()
{
Integer counter = counters().get().get( AlarmPoint.TRIGGER_ACTIVATE );
if( counter == null )
{
return 0;
}
return counter;
}
@Override
public void resetActivateCounter()
{
Map<String, Integer> counters = counters().get();
counters.remove( AlarmPoint.TRIGGER_ACTIVATE );
counters().set( counters );
}
}
}