package org.apache.onami.autobind.scanner.asm;

 /*

  * Licensed to the Apache Software Foundation (ASF) under one or more

  * contributor license agreements.  See the NOTICE file distributed with

  * this work for additional information regarding copyright ownership.

  * The ASF licenses this file to You 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.

  */

 import static java.util.Collections.unmodifiableList;

 import static java.util.logging.Level.WARNING;

 import static java.util.logging.Logger.getLogger;

 import static org.objectweb.asm.ClassReader.SKIP_CODE;

 import static org.objectweb.asm.ClassReader.SKIP_DEBUG;

 import static org.objectweb.asm.ClassReader.SKIP_FRAMES;

 import static org.objectweb.asm.Opcodes.ASM4;

 import java.lang.annotation.Annotation;

 import java.util.HashMap;

 import java.util.LinkedList;

 import java.util.List;

 import java.util.Map;

 import java.util.logging.Logger;

 import org.apache.onami.autobind.scanner.features.ScannerFeature;

 import org.objectweb.asm.AnnotationVisitor;

 import org.objectweb.asm.ClassVisitor;

 /**

  * Visitor implementation to collect field annotation information from class.

  */

 final class AnnotationCollector

     extends ClassVisitor

 {

     public static final int ASM_FLAGS = SKIP_CODE | SKIP_DEBUG | SKIP_FRAMES;

     private final Logger _logger = getLogger( getClass().getName() );

     private String _name;

     private Class<?> _class;

     private boolean _ignore;

     private final Map<String, Annotation> _annotations;

     private final List<ScannerFeature> _features;

     public AnnotationCollector()

     {

         super( ASM4 );

         _features = new LinkedList<ScannerFeature>();

         _annotations = new HashMap<String, Annotation>();

     }

     public void addScannerFeature( ScannerFeature listener )

     {

         _features.add( listener );

     }

     public void removerScannerFeature( ScannerFeature listener )

     {

         _features.remove( listener );

     }

     public List<ScannerFeature> getScannerFeatures()

     {

         return unmodifiableList( _features );

     }

     public void destroy()

     {

         _annotations.clear();

         _class = null;

         _features.clear();

     }

     @Override

     public void visit( int version, int access, String name, String signature, String superName, String[] interfaces )

     {

         _name = name.replace( '/', '.' );

         for ( String interf : interfaces )

         {

             if ( interf.equals( "java/lang/annotation/Annotation" ) )

             {

                 _ignore = true;

                 return;

             }

         }

     }

     @SuppressWarnings( "unchecked" )

     public AnnotationVisitor visitAnnotation( String sig, boolean visible )

     {

         if ( _ignore )

         {

             return null;

         }

         String annotationClassStr = sig.replace( '/', '.' ).substring( 1, sig.length() - 1 );

         if ( _class == null )

         {

             try

             {

                 _class = Thread.currentThread().getContextClassLoader().loadClass( _name );

             }

             catch ( ClassNotFoundException e )

             {

                 _logger.log( WARNING, "Failure while visitAnnotation. Class could not be loaded.", e );

                 return null;

             }

         }

         try

         {

             Class<Annotation> annotationClass =

                 (Class<Annotation>) getClass().getClassLoader().loadClass( annotationClassStr );

             Annotation annotation = _class.getAnnotation( annotationClass );

             _annotations.put( annotationClassStr, annotation );

         }

         catch ( ClassNotFoundException e )

         {

             e.printStackTrace();

             _logger.log( WARNING, "Failure while visitAnnotation. Class could not be loaded.", e );

         }

         return null;

     }

     @SuppressWarnings( "unchecked" )

     @Override

     public void visitEnd()

     {

         if ( !_ignore && _annotations.size() > 0 && !_annotations.containsKey( "javax.enterprise.inject.Alternative" ) )

         {

             for ( ScannerFeature listener : _features )

             {

                 listener.found( (Class<Object>) _class, _annotations );

             }

         }

         _name = null;

         _class = null;

         _ignore = false;

         _annotations.clear();

     }

 }