001    /*****************************************************************************
002     * Copyright (C) PicoContainer Organization. All rights reserved.            *
003     * ------------------------------------------------------------------------- *
004     * The software in this package is published under the terms of the BSD      *
005     * style license a copy of which has been included with this distribution in *
006     * the LICENSE.txt file.                                                     *
007     *                                                                           *
008     * Original code by                                                          *
009     *****************************************************************************/
010    package org.picocontainer.injectors;
011    
012    import java.lang.annotation.Annotation;
013    import java.lang.reflect.AccessibleObject;
014    import java.lang.reflect.Field;
015    import java.lang.reflect.InvocationTargetException;
016    import java.security.AccessController;
017    import java.security.PrivilegedAction;
018    import java.util.ArrayList;
019    import java.util.Arrays;
020    import java.util.Collections;
021    import java.util.List;
022    
023    import org.picocontainer.ComponentMonitor;
024    import org.picocontainer.LifecycleStrategy;
025    import org.picocontainer.NameBinding;
026    import org.picocontainer.Parameter;
027    import org.picocontainer.annotations.Bind;
028    
029    /**
030     * Injection happens after instantiation, and fields are marked as
031     * injection points via a field type.
032     */
033    @SuppressWarnings("serial")
034    public class TypedFieldInjector extends IterativeInjector {
035    
036        /**
037             * Serialization UUID.
038             */
039    
040        private final List<String> classes;
041    
042        public TypedFieldInjector(Object key,
043                                      Class<?> impl,
044                                      Parameter[] parameters,
045                                      ComponentMonitor componentMonitor,
046                                      LifecycleStrategy lifecycleStrategy,
047                                      String classNames) {
048    
049            super(key, impl, parameters, componentMonitor, lifecycleStrategy, true);
050            this.classes = Arrays.asList(classNames.trim().split(" "));
051        }
052    
053        protected void initializeInjectionMembersAndTypeLists() {
054            injectionMembers = new ArrayList<AccessibleObject>();
055            List<Annotation> bindingIds = new ArrayList<Annotation>();
056            final List<Class> typeList = new ArrayList<Class>();
057            final Field[] fields = getFields();
058            for (final Field field : fields) {
059                if (isTypedForInjection(field)) {
060                    injectionMembers.add(field);
061                    typeList.add(box(field.getType()));
062                    bindingIds.add(getBinding(field));
063                }
064            }
065            injectionTypes = typeList.toArray(new Class[0]);
066            bindings = bindingIds.toArray(new Annotation[0]);
067        }
068    
069        private Annotation getBinding(Field field) {
070            Annotation[] annotations = field.getAnnotations();
071            for (Annotation annotation : annotations) {
072                if (annotation.annotationType().isAnnotationPresent(Bind.class)) {
073                    return annotation;
074                }
075            }
076            return null;
077        }
078    
079        protected boolean isTypedForInjection(Field field) {
080            return classes.contains(field.getType().getName());
081        }
082    
083        private Field[] getFields() {
084            return (Field[]) AccessController.doPrivileged(new PrivilegedAction() {
085                public Object run() {
086                    return getComponentImplementation().getDeclaredFields();
087                }
088            });
089        }
090    
091    
092        protected void injectIntoMember(AccessibleObject member, Object componentInstance, Object toInject)
093            throws IllegalAccessException, InvocationTargetException {
094            Field field = (Field) member;
095            field.setAccessible(true);
096            field.set(componentInstance, toInject);
097        }
098    
099        public String getDescriptor() {
100            return "TypedFieldInjector-";
101        }
102    
103        protected NameBinding makeParameterNameImpl(final AccessibleObject member) {
104            return new NameBinding() {
105                public String getName() {
106                    return ((Field) member).getName();
107                }
108            };
109        }
110    
111        List<String> getInjectionFieldTypes() {
112            return Collections.unmodifiableList(classes);
113        }
114    
115    
116    }