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 org.picocontainer.ComponentMonitor;
013 import org.picocontainer.NameBinding;
014 import org.picocontainer.Parameter;
015 import org.picocontainer.PicoContainer;
016 import org.picocontainer.annotations.Bind;
017
018 import java.lang.annotation.Annotation;
019 import java.lang.reflect.*;
020 import java.security.AccessController;
021 import java.security.PrivilegedAction;
022 import java.util.ArrayList;
023 import java.util.Arrays;
024 import java.util.Collections;
025 import java.util.List;
026 import java.util.Set;
027
028 /**
029 * Injection happens after instantiation, and fields are marked as
030 * injection points via a field type.
031 */
032 @SuppressWarnings("serial")
033 public class TypedFieldInjector<T> extends AbstractFieldInjector<T> {
034
035 private final List<String> classes;
036
037 public TypedFieldInjector(Object key,
038 Class<?> impl,
039 Parameter[] parameters,
040 ComponentMonitor componentMonitor,
041 String classNames) {
042 super(key, impl, parameters, componentMonitor, true);
043 this.classes = Arrays.asList(classNames.trim().split(" "));
044 }
045
046 @Override
047 protected void initializeInjectionMembersAndTypeLists() {
048 injectionMembers = new ArrayList<AccessibleObject>();
049 List<Annotation> bindingIds = new ArrayList<Annotation>();
050 final List<Type> typeList = new ArrayList<Type>();
051 final Field[] fields = getFields();
052 for (final Field field : fields) {
053 if (isTypedForInjection(field)) {
054 injectionMembers.add(field);
055 typeList.add(box(field.getType()));
056 bindingIds.add(getBinding(field));
057 }
058 }
059 injectionTypes = typeList.toArray(new Type[0]);
060 bindings = bindingIds.toArray(new Annotation[0]);
061 }
062
063 private Annotation getBinding(Field field) {
064 Annotation[] annotations = field.getAnnotations();
065 for (Annotation annotation : annotations) {
066 if (annotation.annotationType().isAnnotationPresent(Bind.class)) {
067 return annotation;
068 }
069 }
070 return null;
071 }
072
073 protected boolean isTypedForInjection(Field field) {
074 return classes.contains(field.getType().getName());
075 }
076
077 private Field[] getFields() {
078 return AccessController.doPrivileged(new PrivilegedAction<Field[]>() {
079 public Field[] run() {
080 return getComponentImplementation().getDeclaredFields();
081 }
082 });
083 }
084
085
086 protected Object injectIntoMember(AccessibleObject member, Object componentInstance, Object toInject)
087 throws IllegalAccessException, InvocationTargetException {
088 Field field = (Field) member;
089 field.setAccessible(true);
090 field.set(componentInstance, toInject);
091 return null;
092 }
093
094 @Override
095 public String getDescriptor() {
096 return "TypedFieldInjector-";
097 }
098
099 @Override
100 protected NameBinding makeParameterNameImpl(final AccessibleObject member) {
101 return new NameBinding() {
102 public String getName() {
103 return ((Field) member).getName();
104 }
105 };
106 }
107
108 protected Object memberInvocationReturn(Object lastReturn, AccessibleObject member, Object instance) {
109 return instance;
110 }
111
112 List<String> getInjectionFieldTypes() {
113 return Collections.unmodifiableList(classes);
114 }
115
116
117 }