org.eclipse.sisu.bean.BeanLifecycle Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2010-present Sonatype, Inc.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Stuart McCulloch (Sonatype, Inc.) - initial API and implementation
*******************************************************************************/
package org.eclipse.sisu.bean;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.List;
import org.eclipse.sisu.inject.Logs;
/**
* Represents the JSR250 lifecycle for a particular bean type.
*/
final class BeanLifecycle
implements PrivilegedAction
{
// ----------------------------------------------------------------------
// Constants
// ----------------------------------------------------------------------
private static final Method[] NO_METHODS = {};
static final BeanLifecycle NO_OP = new BeanLifecycle( null, null );
// ----------------------------------------------------------------------
// Implementation fields
// ----------------------------------------------------------------------
private final Method[] startMethods;
private final Method[] stopMethods;
// ----------------------------------------------------------------------
// Constructors
// ----------------------------------------------------------------------
/**
* Creates a new lifecycle based on the given start and stop methods.
*
* @param startMethods The methods used to start the bean; from subclass to superclass
* @param stopMethods The methods used to stop the bean; from subclass to superclass
*/
BeanLifecycle( final List startMethods, final List stopMethods )
{
this.startMethods = toArray( startMethods );
this.stopMethods = toArray( stopMethods );
// ensure we can invoke all methods
AccessController.doPrivileged( this );
}
// ----------------------------------------------------------------------
// Public methods
// ----------------------------------------------------------------------
/**
* @return {@code true} if this lifecycle can be started; otherwise {@code false}
*/
public boolean isStartable()
{
return startMethods.length > 0;
}
/**
* @return {@code true} if this lifecycle can be stopped; otherwise {@code false}
*/
public boolean isStoppable()
{
return stopMethods.length > 0;
}
/**
* Starts the given bean by invoking the methods defined in this lifecycle.
*
* @param bean The bean to start
*/
public void start( final Object bean )
{
Logs.trace( "PostConstruct: <>", bean, null );
// start superclass before subclass, bail out at the first failure
int i = startMethods.length - 1;
try
{
for ( ; i >= 0; i-- )
{
startMethods[i].invoke( bean );
}
}
catch ( final Throwable e ) // NOPMD see Logs.catchThrowable
{
final Throwable cause = e instanceof InvocationTargetException ? e.getCause() : e;
Logs.catchThrowable( cause );
try
{
Logs.warn( "Error starting: {}", startMethods[i], cause );
}
finally
{
Logs.throwUnchecked( cause );
}
}
}
/**
* Stops the given bean by invoking the methods defined in this lifecycle.
*
* @param bean The bean to stop
*/
@SuppressWarnings( "finally" )
public void stop( final Object bean )
{
Logs.trace( "PreDestroy: <>", bean, null );
// stop subclass before superclass, log any failures along the way
for ( int i = 0; i < stopMethods.length; i++ )
{
try
{
stopMethods[i].invoke( bean );
}
catch ( final Throwable e ) // NOPMD see Logs.catchThrowable
{
final Throwable cause = e instanceof InvocationTargetException ? e.getCause() : e;
Logs.catchThrowable( cause );
try
{
Logs.warn( "Problem stopping: {}", stopMethods[i], cause );
}
finally
{
continue; // ignore any logging exceptions and continue stopping
}
}
}
}
// ----------------------------------------------------------------------
// PrivilegedAction methods
// ----------------------------------------------------------------------
public Void run()
{
AccessibleObject.setAccessible( startMethods, true );
AccessibleObject.setAccessible( stopMethods, true );
return null;
}
// ----------------------------------------------------------------------
// Implementation methods
// ----------------------------------------------------------------------
private static Method[] toArray( final List methods )
{
return null != methods && !methods.isEmpty() ? methods.toArray( new Method[methods.size()] ) : NO_METHODS;
}
}