PandacubeFr/BungeeCord
1
0
Fork 0
Code Releases Activity

Add home grown event bus

Browse Source
This commit is contained in:
md_5
2013-05-14 11:30:08 +10:00
parent aefe3333a9
commit 21a354fa75
9 changed files with 238 additions and 457 deletions
Download Patch File Download Diff File Expand all files Collapse all files

163
event/src/main/java/net/md_5/bungee/event/EventBus.java Normal file
View File

@@ -0,0 +1,163 @@
package net.md_5.bungee.event;
import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.MessageFormat;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.logging.Level;
import java.util.logging.Logger;
public class EventBus
{
private final Map<Class<?>, Map<Object, Method[]>> eventToHandler = new HashMap<>();
private final ReadWriteLock lock = new ReentrantReadWriteLock();
private final Logger logger;
private final Class<? extends Annotation>[] annotations;
public EventBus()
{
this( null, (Class<? extends Annotation>[]) null );
}
public EventBus(Logger logger)
{
this( logger, (Class<? extends Annotation>[]) null );
}
@SuppressWarnings("unchecked")
public EventBus(Class<? extends Annotation>... annotations)
{
this( null, annotations );
}
@SuppressWarnings("unchecked")
public EventBus(Logger logger, Class<? extends Annotation>... annotations)
{
this.logger = ( logger == null ) ? Logger.getGlobal() : logger;
this.annotations = ( annotations == null || annotations.length == 0 ) ? new Class[]
{
EventHandler.class
} : annotations;
}
public void post(Object event)
{
lock.readLock().lock();
try
{
Map<Object, Method[]> handlers = eventToHandler.get( event.getClass() );
if ( handlers != null )
{
for ( Map.Entry<Object, Method[]> handler : handlers.entrySet() )
{
for ( Method method : handler.getValue() )
{
try
{
method.invoke( handler.getKey(), event );
} catch ( IllegalAccessException ex )
{
throw new Error( "Method became inaccessible: " + event, ex );
} catch ( IllegalArgumentException ex )
{
throw new Error( "Method rejected target/argument: " + event, ex );
} catch ( InvocationTargetException ex )
{
logger.log( Level.WARNING, MessageFormat.format( "Error dispatching event {0} to listener {1}", event, handler.getKey() ), ex.getCause() );
}
}
}
}
} finally
{
lock.readLock().unlock();
}
}
private Map<Class<?>, Set<Method>> findHandlers(Object listener)
{
Map<Class<?>, Set<Method>> handler = new HashMap<>();
for ( Method m : listener.getClass().getDeclaredMethods() )
{
for ( Class<? extends Annotation> annotation : annotations )
{
if ( m.isAnnotationPresent( annotation ) )
{
Class<?>[] params = m.getParameterTypes();
if ( params.length != 1 )
{
logger.log( Level.INFO, "Method {0} in class {1} annotated with {2} does not have single argument", new Object[]
{
m, listener.getClass(), annotation
} );
continue;
}
Set<Method> existing = handler.get( params[0] );
if ( existing == null )
{
existing = new HashSet<>();
handler.put( params[0], existing );
}
existing.add( m );
break;
}
}
}
return handler;
}
public void register(Object listener)
{
Map<Class<?>, Set<Method>> handler = findHandlers( listener );
lock.writeLock().lock();
try
{
for ( Map.Entry<Class<?>, Set<Method>> e : handler.entrySet() )
{
Map<Object, Method[]> a = eventToHandler.get( e.getKey() );
if ( a == null )
{
a = new HashMap<>();
eventToHandler.put( e.getKey(), a );
}
Method[] baked = new Method[ e.getValue().size() ];
a.put( listener, e.getValue().toArray( baked ) );
}
} finally
{
lock.writeLock().unlock();
}
}
public void unregister(Object listener)
{
Map<Class<?>, Set<Method>> handler = findHandlers( listener );
lock.writeLock().lock();
try
{
for ( Map.Entry<Class<?>, Set<Method>> e : handler.entrySet() )
{
Map<Object, Method[]> a = eventToHandler.get( e.getKey() );
if ( a != null )
{
a.remove( listener );
if ( a.isEmpty() )
{
eventToHandler.remove( e.getKey() );
}
}
}
} finally
{
lock.writeLock().unlock();
}
}
}

13
event/src/main/java/net/md_5/bungee/event/EventHandler.java Normal file
View File

@@ -0,0 +1,13 @@
package net.md_5.bungee.event;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface EventHandler
{
}

42
event/src/test/java/net/md_5/bungee/event/EventBusTest.java Normal file
View File

@@ -0,0 +1,42 @@
package net.md_5.bungee.event;
import java.util.concurrent.CountDownLatch;
import org.junit.Assert;
import org.junit.Test;
public class EventBusTest
{
private final EventBus bus = new EventBus();
private final CountDownLatch latch = new CountDownLatch( 2 );
@Test
public void testNestedEvents()
{
bus.register( this );
bus.post( new FirstEvent() );
Assert.assertEquals( latch.getCount(), 0 );
}
@EventHandler
public void firstListener(FirstEvent event)
{
bus.post( new SecondEvent() );
Assert.assertEquals( latch.getCount(), 1 );
latch.countDown();
}
@EventHandler
public void secondListener(SecondEvent event)
{
latch.countDown();
}
public static class FirstEvent
{
}
public static class SecondEvent
{
}
}