/*
* Copyright (c) 2010, Rickard Öberg. All Rights Reserved.
*
* 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.runtime.bootstrap;
import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.Map;
import org.qi4j.api.common.AppliesTo;
import org.qi4j.api.common.AppliesToFilter;
import org.qi4j.api.common.ConstructionException;
import org.qi4j.api.constraint.Constraint;
import org.qi4j.runtime.composite.ConcernModel;
import org.qi4j.runtime.composite.ConstraintDeclaration;
import org.qi4j.runtime.composite.FragmentClassLoader;
import org.qi4j.runtime.composite.MixinModel;
import org.qi4j.runtime.composite.SideEffectModel;
/**
* This helper is used when building the application model. It keeps track
* of already created classloaders and various models
*/
public class AssemblyHelper
{
Map<Class, Class> instantiationClasses = new HashMap<>();
Map<Class, ConstraintDeclaration> constraintDeclarations = new HashMap<>();
Map<ClassLoader, FragmentClassLoader> modifierClassLoaders = new HashMap<>();
Map<Class<?>, AppliesToFilter> appliesToInstances = new HashMap<>();
public MixinModel getMixinModel( Class mixinClass )
{
return new MixinModel( mixinClass, instantiationClass( mixinClass ) );
}
public ConcernModel getConcernModel( Class concernClass )
{
return new ConcernModel( concernClass, instantiationClass( concernClass ) );
}
public SideEffectModel getSideEffectModel( Class sideEffectClass )
{
return new SideEffectModel( sideEffectClass, instantiationClass( sideEffectClass ) );
}
private Class instantiationClass( Class fragmentClass )
{
Class instantiationClass = fragmentClass;
if( !InvocationHandler.class.isAssignableFrom( fragmentClass ) )
{
instantiationClass = instantiationClasses.get( fragmentClass );
if( instantiationClass == null )
{
try
{
FragmentClassLoader fragmentLoader = getModifierClassLoader( fragmentClass.getClassLoader() );
instantiationClass = fragmentLoader.loadFragmentClass( fragmentClass );
instantiationClasses.put( fragmentClass, instantiationClass );
}
catch( ClassNotFoundException | VerifyError e )
{
throw new ConstructionException( "Could not generate mixin subclass " + fragmentClass.getName(), e );
}
}
}
return instantiationClass;
}
private FragmentClassLoader getModifierClassLoader( ClassLoader classLoader )
{
FragmentClassLoader cl = modifierClassLoaders.get( classLoader );
if( cl == null )
{
cl = new FragmentClassLoader( classLoader );
modifierClassLoaders.put( classLoader, cl );
}
return cl;
}
public boolean appliesTo( Class<?> fragmentClass, Method method, Iterable<Class<?>> types, Class<?> mixinClass )
{
AppliesToFilter appliesToFilter = appliesToInstances.get( fragmentClass );
if( appliesToFilter == null )
{
appliesToFilter = createAppliesToFilter( fragmentClass );
appliesToInstances.put( fragmentClass, appliesToFilter );
}
for( Class<?> compositeType : types )
{
if( appliesToFilter.appliesTo( method, mixinClass, compositeType, fragmentClass ) )
{
return true;
}
}
return false;
}
public AppliesToFilter createAppliesToFilter( Class<?> fragmentClass )
{
AppliesToFilter result = null;
if( !InvocationHandler.class.isAssignableFrom( fragmentClass ) )
{
result = new TypedFragmentAppliesToFilter();
if( Modifier.isAbstract( fragmentClass.getModifiers() ) )
{
result = new AndAppliesToFilter( result, new ImplementsMethodAppliesToFilter() );
}
}
result = applyAppliesTo( result, fragmentClass );
if( result == null )
{
return AppliesToFilter.ALWAYS;
}
return result;
}
private AppliesToFilter applyAppliesTo( AppliesToFilter existing, Class<?> modifierClass )
{
AppliesTo appliesTo = modifierClass.getAnnotation( AppliesTo.class );
if( appliesTo != null )
{
// Use "or" for all filters specified in the annotation
AppliesToFilter appliesToAnnotation = null;
for( Class<?> appliesToClass : appliesTo.value() )
{
AppliesToFilter filter;
if( AppliesToFilter.class.isAssignableFrom( appliesToClass ) )
{
try
{
filter = (AppliesToFilter) appliesToClass.newInstance();
}
catch( Exception e )
{
throw new ConstructionException( e );
}
}
else if( Annotation.class.isAssignableFrom( appliesToClass ) )
{
filter = new AnnotationAppliesToFilter( appliesToClass );
}
else // Type check
{
filter = new TypeCheckAppliesToFilter( appliesToClass );
}
if( appliesToAnnotation == null )
{
appliesToAnnotation = filter;
}
else
{
appliesToAnnotation = new OrAppliesToFilter( appliesToAnnotation, filter );
}
}
// Add to the rest of the rules using "and"
if( existing == null )
{
return appliesToAnnotation;
}
else
{
return new AndAppliesToFilter( existing, appliesToAnnotation );
}
}
return existing;
}
public boolean appliesTo( Class<? extends Constraint<?, ?>> constraint,
Class<? extends Annotation> annotationType,
Type valueType
)
{
ConstraintDeclaration constraintDeclaration = constraintDeclarations.get( constraint );
if( constraintDeclaration == null )
{
constraintDeclaration = new ConstraintDeclaration( constraint );
constraintDeclarations.put( constraint, constraintDeclaration );
}
return constraintDeclaration.appliesTo( annotationType, valueType );
}
}