实例化bean和依赖注入是在AbstractBeanFactory的入口,但是实际还是在AbstractAutowireCapableBeanFactory这个类中实现。bean实例化的时候有两种基本的方式,就是一用默认构造函数,一是在xml配置自己的可带参数的构造函数,这两种方式在spring中实例的流程是不一样的,对应的BeanDefinition的数据也是不同。所以这里就根据这两种实例化的方式来讲解这个至关重要的AbstractAutowireCapableBeanFactor类。
- 默认构造函数实例化的方式
这里首先画出实例化的时序图:如下
- doCreateBean方法:通过上面的图可以看出在AbstractAutowireCapableBeanFactory的入口实例化bean是createBean方法。但是createBean方法其实并没有做些什么,唯一的工作判断是否可以实例化。重点还是在另外一个方法中。就是doCreateBean方法:我把这个方法细分为两大部分:一实例化bean,二属性依赖注入。可见下面标红的地方。
protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, final Object[] args) { // Instantiate the bean. if("org.springframework.aop.aspectj.AspectJPointcutAdvisor#0".equals(beanName)){ System.out.println(beanName); } BeanWrapper instanceWrapper = null; if (mbd.isSingleton()) { instanceWrapper = this.factoryBeanInstanceCache.remove(beanName); } if (instanceWrapper == null) { //这里为实例化bean的地方,还是调用本类的createBeanInstance方法 instanceWrapper = createBeanInstance(beanName, mbd, args); } final Object bean = (instanceWrapper != null ? instanceWrapper.getWrappedInstance() : null); Class beanType = (instanceWrapper != null ? instanceWrapper.getWrappedClass() : null); // Allow post-processors to modify the merged bean definition. synchronized (mbd.postProcessingLock) { if (!mbd.postProcessed) { applyMergedBeanDefinitionPostProcessors(mbd, beanType, beanName); mbd.postProcessed = true; } } // Eagerly cache singletons to be able to resolve circular references // even when triggered by lifecycle interfaces like BeanFactoryAware. boolean earlySingletonExposure = (mbd.isSingleton() && this.allowCircularReferences && isSingletonCurrentlyInCreation(beanName)); if (earlySingletonExposure) { if (logger.isDebugEnabled()) { logger.debug("Eagerly caching bean '" + beanName + "' to allow for resolving potential circular references"); } addSingletonFactory(beanName, new ObjectFactory() { public Object getObject() throws BeansException { return getEarlyBeanReference(beanName, mbd, bean); } }); } // Initialize the bean instance. Object exposedObject = bean; try { //这里是设置bean的属性,也就是注入的发生 populateBean(beanName, mbd, instanceWrapper); if (exposedObject != null) { //这里也是一个重点,主要是调用BeanPostProcessor,在实例化前,同时AOP的实现也是跟这里有着莫大的关联。详细见下面的分析 exposedObject = initializeBean(beanName, exposedObject, mbd); } } catch (Throwable ex) { if (ex instanceof BeanCreationException && beanName.equals(((BeanCreationException) ex).getBeanName())) { throw (BeanCreationException) ex; } else { throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Initialization of bean failed", ex); } } if (earlySingletonExposure) { Object earlySingletonReference = getSingleton(beanName, false); if (earlySingletonReference != null) { if (exposedObject == bean) { exposedObject = earlySingletonReference; } else if (!this.allowRawInjectionDespiteWrapping && hasDependentBean(beanName)) { String[] dependentBeans = getDependentBeans(beanName); Set<String> actualDependentBeans = new LinkedHashSet<String>(dependentBeans.length); for (String dependentBean : dependentBeans) { if (!removeSingletonIfCreatedForTypeCheckOnly(dependentBean)) { actualDependentBeans.add(dependentBean); } } if (!actualDependentBeans.isEmpty()) { throw new BeanCurrentlyInCreationException(beanName, "Bean with name '" + beanName + "' has been injected into other beans [" + StringUtils.collectionToCommaDelimitedString(actualDependentBeans) + "] in its raw version as part of a circular reference, but has eventually been " + "wrapped. This means that said other beans do not use the final version of the " + "bean. This is often the result of over-eager type matching - consider using " + "'getBeanNamesOfType' with the 'allowEagerInit' flag turned off, for example."); } } } } // Register bean as disposable. try { registerDisposableBeanIfNecessary(beanName, bean, mbd); } catch (BeanDefinitionValidationException ex) { throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Invalid destruction signature", ex); } return exposedObject; }
- createBeanInstance方法:这里的createBeanInstance是实例化bean的地方。其中从时序图中看到会调用到 SimpleInstantiationStrategy类来实例化。而SimpleInstantiationStrategy这个是通过工厂方法得到的。其实本身通过工厂得到的是CglibSubclassingInstantiationStrategy,但是这个类继承了SimpleInstantiationStrategy。在SimpleInstantiationStrategy类中instantiate如下:其实就是通过BeanDefinition得到class,然后得到默认的构造函数,最后实例化。
protected BeanWrapper createBeanInstance(String beanName, RootBeanDefinition mbd, Object[] args) { // Make sure bean class is actually resolved at this point. Class beanClass = resolveBeanClass(mbd, beanName); if (beanClass != null && !Modifier.isPublic(beanClass.getModifiers()) && !mbd.isNonPublicAccessAllowed()) { throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Bean class isn't public, and non-public access not allowed: " + beanClass.getName()); } if (mbd.getFactoryMethodName() != null) { return instantiateUsingFactoryMethod(beanName, mbd, args); } // Shortcut when re-creating the same bean... boolean resolved = false; boolean autowireNecessary = false; if (args == null) { synchronized (mbd.constructorArgumentLock) { if (mbd.resolvedConstructorOrFactoryMethod != null) { resolved = true; autowireNecessary = mbd.constructorArgumentsResolved; } } } if (resolved) { if (autowireNecessary) { return autowireConstructor(beanName, mbd, null, null); } else { return instantiateBean(beanName, mbd); } } // Need to determine the constructor... Constructor[] ctors = determineConstructorsFromBeanPostProcessors(beanClass, beanName); if (ctors != null || mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_CONSTRUCTOR || mbd.hasConstructorArgumentValues() || !ObjectUtils.isEmpty(args)) { //如果BeanDefinition中有constructorArgumentValues属性,则是调用相应的构造函数,而不是默认的构造函数。这里会在其他的地方详细解释 return autowireConstructor(beanName, mbd, ctors, args); } //调用本类的instantiateBean方法,其实就是用默认的无参数构造方法实例化bean return instantiateBean(beanName, mbd); } protected BeanWrapper instantiateBean(final String beanName, final RootBeanDefinition mbd) { try { Object beanInstance; final BeanFactory parent = this; if (System.getSecurityManager() != null) { beanInstance = AccessController.doPrivileged(new PrivilegedAction<Object>() { public Object run() { //这里使用工厂方法得到实例化的策略,默认为CglibSubclassingInstantiationStrategy,并会调用到其父类SimpleInstantiationStrategy的instantiate方法,通过BeanDefinition得到class然后获得默认的无参构造方法实例化bean //当然在SimpleInstantiationStrategy也可以使用CGLIB来实例化,有兴趣的可以自己查看 return getInstantiationStrategy().instantiate(mbd, beanName, parent); } }, getAccessControlContext()); } else { beanInstance = getInstantiationStrategy().instantiate(mbd, beanName, parent); } BeanWrapper bw = new BeanWrapperImpl(beanInstance); initBeanWrapper(bw); return bw; } catch (Throwable ex) { throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Instantiation of bean failed", ex); } }
- populateBean方法:这个方法就是设置bean属性的,也就是依赖注入的过程。这个过程是相对比较复杂的。要知道spring最得人心的其中之一特性,肯定是不会那么简单的了。
protected void populateBean(String beanName, AbstractBeanDefinition mbd, BeanWrapper bw) { //通过BeanDefinition得到PropertyValues,PropertyValues是什么意思见另外一批解释 PropertyValues pvs = mbd.getPropertyValues(); if (bw == null) { if (!pvs.isEmpty()) { throw new BeanCreationException( mbd.getResourceDescription(), beanName, "Cannot apply property values to null instance"); } else { // Skip property population phase for null instance. return; } } // Give any InstantiationAwareBeanPostProcessors the opportunity to modify the // state of the bean before properties are set. This can be used, for example, // to support styles of field injection. boolean continueWithPropertyPopulation = true; //先判断BeanDefinition是否为合成的,用户配置xml的都是false。而这里是否有有初始化意识的BeanPostProcessor,其中AOP中AspectJAwareAdvisorAutoProxyCreator就是一个 if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) { for (BeanPostProcessor bp : getBeanPostProcessors()) { if (bp instanceof InstantiationAwareBeanPostProcessor) { InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp; if (!ibp.postProcessAfterInstantiation(bw.getWrappedInstance(), beanName)) { continueWithPropertyPopulation = false; break; } } } } if (!continueWithPropertyPopulation) { return; } //这里开始依赖注入,如果xml中设置了autowire为byName或者byType的话会调用下面的,如果没有设置为默认的则都不会调用,一般情况下不会这是自动装配,虽然很方便 //但是维护起来还是比较麻烦,再则没有使用一看xml配置文件就能够很方便 if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_NAME || mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_TYPE) { MutablePropertyValues newPvs = new MutablePropertyValues(pvs); // Add property values based on autowire by name if applicable. if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_NAME) { autowireByName(beanName, mbd, bw, newPvs); } // Add property values based on autowire by type if applicable. if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_TYPE) { autowireByType(beanName, mbd, bw, newPvs); } pvs = newPvs; } boolean hasInstAwareBpps = hasInstantiationAwareBeanPostProcessors(); boolean needsDepCheck = (mbd.getDependencyCheck() != RootBeanDefinition.DEPENDENCY_CHECK_NONE); if (hasInstAwareBpps || needsDepCheck) { PropertyDescriptor[] filteredPds = filterPropertyDescriptorsForDependencyCheck(bw); if (hasInstAwareBpps) { for (BeanPostProcessor bp : getBeanPostProcessors()) { if (bp instanceof InstantiationAwareBeanPostProcessor) { InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp; pvs = ibp.postProcessPropertyValues(pvs, filteredPds, bw.getWrappedInstance(), beanName); if (pvs == null) { return; } } } } if (needsDepCheck) { checkDependencies(beanName, mbd, filteredPds, pvs); } } applyPropertyValues(beanName, mbd, bw, pvs); }
- autowireByName方法:按name自动装配。可以看到依赖注入的时候会检测配置的自动装入,如果发现不是默认的,而是byName或者byType的时候就会自动的装入了。这里的byName还是比较的简单,通过javabean的内省Introspector得到所有的PropertyDescriptor,然后通过PropertyDescriptor得到propertyName。这里的在CachedIntrospectionResults类中。读者如果有兴趣可自行查询。
protected void autowireByName( String beanName, AbstractBeanDefinition mbd, BeanWrapper bw, MutablePropertyValues pvs) { //得到BeanDefinition的所有propertyNames,这里得到propertyNames是通过javabean得到的的,有兴趣的可以自己查询 String[] propertyNames = unsatisfiedNonSimpleProperties(mbd, bw); for (String propertyName : propertyNames) { if (containsBean(propertyName)) { Object bean = getBean(propertyName); //通过propertyName向容器中拿到bean,然后添加到BeanDefinition的MutablePropertyValues中 pvs.add(propertyName, bean); registerDependentBean(propertyName, beanName); if (logger.isDebugEnabled()) { logger.debug("Added autowiring by name from bean name '" + beanName + "' via property '" + propertyName + "' to bean named '" + propertyName + "'"); } } else { if (logger.isTraceEnabled()) { logger.trace("Not autowiring property '" + propertyName + "' of bean '" + beanName + "' by name: no matching bean found"); } } } }
- autowireByType方法:按类型自动装配。 如果自动装配是byType的话,就比较的麻烦。并且如果配置文件中有多个你设置的class怎么办呢?spring就会报错了。看源代码应该是有避免报错的方法。这里就先不说了。在resolveDependency方法的调用中会最后会调用到DefaultListableBeanFactory中的getBeanNamesForType,通过名称就可以看出意思就是通过class得到一批beannames。如果刚好只有一个,然后有是通过调用getBean来得到bean然后注入的。
protected void autowireByType(
String beanName, AbstractBeanDefinition mbd, BeanWrapper bw, MutablePropertyValues pvs) {
TypeConverter converter = getCustomTypeConverter();
if (converter == null) {
converter = bw;
}
Set<String> autowiredBeanNames = new LinkedHashSet<String>(4);
String[] propertyNames = unsatisfiedNonSimpleProperties(mbd, bw);
for (String propertyName : propertyNames) {
try {
PropertyDescriptor pd = bw.getPropertyDescriptor(propertyName);
// Don't try autowiring by type for type Object: never makes sense,
// even if it technically is a unsatisfied, non-simple property.
if (!Object.class.equals(pd.getPropertyType())) {
MethodParameter methodParam = BeanUtils.getWriteMethodParameter(pd);
// Do not allow eager init for type matching in case of a prioritized post-processor.
boolean eager = !PriorityOrdered.class.isAssignableFrom(bw.getWrappedClass());
DependencyDescriptor desc = new AutowireByTypeDependencyDescriptor(methodParam, eager);
Object autowiredArgument = resolveDependency(desc, beanName, autowiredBeanNames, converter);
if (autowiredArgument != null) {
pvs.add(propertyName, autowiredArgument);
}
for (String autowiredBeanName : autowiredBeanNames) {
registerDependentBean(autowiredBeanName, beanName);
if (logger.isDebugEnabled()) {
logger.debug("Autowiring by type from bean name '" + beanName + "' via property '" +
propertyName + "' to bean named '" + autowiredBeanName + "'");
}
}
autowiredBeanNames.clear();
}
}
catch (BeansException ex) {
throw new UnsatisfiedDependencyException(mbd.getResourceDescription(), beanName, propertyName, ex);
}
}
}
- applyPropertyValues:这里做的大部分工作就是依赖的准备工作。其中上面还只是讲了像BeanDefinition中的MutablePropertyValues添加属性,并且解析xml的时候也会忘BeanDefinition注入属性,但是这里的属性是需要转换的。因为即使你在xml中配置为<property name="addStmt" value="2" />,它对应的是TypedStringValue,如果配置的是list,实际的类型为ManagedList。而如果是<property name="book" ref="book" />的话则为RuntimeBeanNameReference,等等其他的类型也是要转换的,即使依赖注入的时候像上面属性添加的实际是Object类型了是最终的类型了,也要通过resolveValueIfNecessary转换一下。而在这个方法中如果是Object就原样返回。
protected void applyPropertyValues(String beanName, BeanDefinition mbd, BeanWrapper bw, PropertyValues pvs) { if (pvs == null || pvs.isEmpty()) { return; } MutablePropertyValues mpvs = null; List<PropertyValue> original; if (System.getSecurityManager()!= null) { if (bw instanceof BeanWrapperImpl) { ((BeanWrapperImpl) bw).setSecurityContext(getAccessControlContext()); } } if (pvs instanceof MutablePropertyValues) { mpvs = (MutablePropertyValues) pvs; if (mpvs.isConverted()) { // Shortcut: use the pre-converted values as-is. try { bw.setPropertyValues(mpvs); return; } catch (BeansException ex) { throw new BeanCreationException( mbd.getResourceDescription(), beanName, "Error setting property values", ex); } } original = mpvs.getPropertyValueList(); } else { original = Arrays.asList(pvs.getPropertyValues()); } TypeConverter converter = getCustomTypeConverter(); if (converter == null) { converter = bw; } BeanDefinitionValueResolver valueResolver = new BeanDefinitionValueResolver(this, beanName, mbd, converter); // Create a deep copy, resolving any references for values. List<PropertyValue> deepCopy = new ArrayList<PropertyValue>(original.size()); boolean resolveNecessary = false; for (PropertyValue pv : original) { if (pv.isConverted()) { deepCopy.add(pv); } else { String propertyName = pv.getName(); Object originalValue = pv.getValue(); //这里通过valueResolver得到值,因为spring中如果配置的是string,知己PropertyValue中的值为TypedStringValue的类型,如果配置的是list,实际的类型为ManagedList。所以还需转换一下。这里的流程也就到了时序图中的4.1 Object resolvedValue = valueResolver.resolveValueIfNecessary(pv, originalValue); Object convertedValue = resolvedValue; boolean convertible = bw.isWritableProperty(propertyName) && !PropertyAccessorUtils.isNestedOrIndexedProperty(propertyName); if (convertible) { convertedValue = convertForProperty(resolvedValue, propertyName, bw, converter); } // Possibly store converted value in merged bean definition, // in order to avoid re-conversion for every created bean instance. if (resolvedValue == originalValue) { if (convertible) { pv.setConvertedValue(convertedValue); } deepCopy.add(pv); } else if (convertible && originalValue instanceof TypedStringValue && !((TypedStringValue) originalValue).isDynamic() && !(convertedValue instanceof Collection || ObjectUtils.isArray(convertedValue))) { pv.setConvertedValue(convertedValue); deepCopy.add(pv); } else { resolveNecessary = true; deepCopy.add(new PropertyValue(pv, convertedValue)); } } } if (mpvs != null && !resolveNecessary) { mpvs.setConverted(); } // Set our (possibly massaged) deep copy. try { bw.setPropertyValues(new MutablePropertyValues(deepCopy)); } catch (BeansException ex) { throw new BeanCreationException( mbd.getResourceDescription(), beanName, "Error setting property values", ex); } }
- resolveValueIfNecessary方法:在时序图4.1中。这个方法在BeanDefinitionValueResolver类中,它的工作就是转换。转换为实际的类型。通过这里之后所有的依赖准备工作都准备好了。
public Object resolveValueIfNecessary(Object argName, Object value) { // We must check each value to see whether it requires a runtime reference // to another bean to be resolved. if (value instanceof RuntimeBeanReference) { RuntimeBeanReference ref = (RuntimeBeanReference) value; return resolveReference(argName, ref); } else if (value instanceof RuntimeBeanNameReference) { String refName = ((RuntimeBeanNameReference) value).getBeanName(); refName = String.valueOf(evaluate(refName)); if (!this.beanFactory.containsBean(refName)) { throw new BeanDefinitionStoreException( "Invalid bean name '" + refName + "' in bean reference for " + argName); } return refName; } else if (value instanceof BeanDefinitionHolder) { // Resolve BeanDefinitionHolder: contains BeanDefinition with name and aliases. BeanDefinitionHolder bdHolder = (BeanDefinitionHolder) value; return resolveInnerBean(argName, bdHolder.getBeanName(), bdHolder.getBeanDefinition()); } else if (value instanceof BeanDefinition) { // Resolve plain BeanDefinition, without contained name: use dummy name. BeanDefinition bd = (BeanDefinition) value; return resolveInnerBean(argName, "(inner bean)", bd); } else if (value instanceof ManagedArray) { // May need to resolve contained runtime references. ManagedArray array = (ManagedArray) value; Class elementType = array.resolvedElementType; if (elementType == null) { String elementTypeName = array.getElementTypeName(); if (StringUtils.hasText(elementTypeName)) { try { elementType = ClassUtils.forName(elementTypeName, this.beanFactory.getBeanClassLoader()); array.resolvedElementType = elementType; } catch (Throwable ex) { // Improve the message by showing the context. throw new BeanCreationException( this.beanDefinition.getResourceDescription(), this.beanName, "Error resolving array type for " + argName, ex); } } else { elementType = Object.class; } } return resolveManagedArray(argName, (List<?>) value, elementType); } else if (value instanceof ManagedList) { // May need to resolve contained runtime references. return resolveManagedList(argName, (List<?>) value); } else if (value instanceof ManagedSet) { // May need to resolve contained runtime references. return resolveManagedSet(argName, (Set<?>) value); } else if (value instanceof ManagedMap) { // May need to resolve contained runtime references. return resolveManagedMap(argName, (Map<?, ?>) value); } else if (value instanceof ManagedProperties) { Properties original = (Properties) value; Properties copy = new Properties(); for (Map.Entry propEntry : original.entrySet()) { Object propKey = propEntry.getKey(); Object propValue = propEntry.getValue(); if (propKey instanceof TypedStringValue) { propKey = evaluate((TypedStringValue) propKey); } if (propValue instanceof TypedStringValue) { propValue = evaluate((TypedStringValue) propValue); } copy.put(propKey, propValue); } return copy; } else if (value instanceof TypedStringValue) { // Convert value to target type here. TypedStringValue typedStringValue = (TypedStringValue) value; Object valueObject = evaluate(typedStringValue); try { Class<?> resolvedTargetType = resolveTargetType(typedStringValue); if (resolvedTargetType != null) { return this.typeConverter.convertIfNecessary(valueObject, resolvedTargetType); } else { return valueObject; } } catch (Throwable ex) { // Improve the message by showing the context. throw new BeanCreationException( this.beanDefinition.getResourceDescription(), this.beanName, "Error converting typed String value for " + argName, ex); } } else { return evaluate(value); } } /** * Evaluate the given value as an expression, if necessary. * @param value the candidate value (may be an expression) * @return the resolved value */ protected Object evaluate(TypedStringValue value) { Object result = this.beanFactory.evaluateBeanDefinitionString(value.getValue(), this.beanDefinition); if (result != value.getValue()) { value.setDynamic(); } return result; }
- setPropertyValue:这里为BeanWrapperImpl中的方法。也是上面applyPropertyValues会调用的。这里就是依赖注入实现的地方。这里还是通过javabean的机制,通过PropertyDescriptor得到属性的writeMethod,也就是你类中的set方法。然后通过反正注入。
private void setPropertyValue(PropertyTokenHolder tokens, PropertyValue pv) throws BeansException { String propertyName = tokens.canonicalName; String actualName = tokens.actualName; if (tokens.keys != null) { // Apply indexes and map keys: fetch value for all keys but the last one. PropertyTokenHolder getterTokens = new PropertyTokenHolder(); getterTokens.canonicalName = tokens.canonicalName; getterTokens.actualName = tokens.actualName; getterTokens.keys = new String[tokens.keys.length - 1]; System.arraycopy(tokens.keys, 0, getterTokens.keys, 0, tokens.keys.length - 1); Object propValue; try { propValue = getPropertyValue(getterTokens); } catch (NotReadablePropertyException ex) { throw new NotWritablePropertyException(getRootClass(), this.nestedPath + propertyName, "Cannot access indexed value in property referenced " + "in indexed property path '" + propertyName + "'", ex); } // Set value for last key. String key = tokens.keys[tokens.keys.length - 1]; if (propValue == null) { throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + propertyName, "Cannot access indexed value in property referenced " + "in indexed property path '" + propertyName + "': returned null"); } else if (propValue.getClass().isArray()) { PropertyDescriptor pd = getCachedIntrospectionResults().getPropertyDescriptor(actualName); Class requiredType = propValue.getClass().getComponentType(); int arrayIndex = Integer.parseInt(key); Object oldValue = null; try { if (isExtractOldValueForEditor()) { oldValue = Array.get(propValue, arrayIndex); } Object convertedValue = convertIfNecessary(propertyName, oldValue, pv.getValue(), requiredType, new PropertyTypeDescriptor(pd, new MethodParameter(pd.getReadMethod(), -1), requiredType)); Array.set(propValue, arrayIndex, convertedValue); } catch (IndexOutOfBoundsException ex) { throw new InvalidPropertyException(getRootClass(), this.nestedPath + propertyName, "Invalid array index in property path '" + propertyName + "'", ex); } } else if (propValue instanceof List) { PropertyDescriptor pd = getCachedIntrospectionResults().getPropertyDescriptor(actualName); Class requiredType = GenericCollectionTypeResolver.getCollectionReturnType( pd.getReadMethod(), tokens.keys.length); List list = (List) propValue; int index = Integer.parseInt(key); Object oldValue = null; if (isExtractOldValueForEditor() && index < list.size()) { oldValue = list.get(index); } Object convertedValue = convertIfNecessary(propertyName, oldValue, pv.getValue(), requiredType, new PropertyTypeDescriptor(pd, new MethodParameter(pd.getReadMethod(), -1), requiredType)); if (index < list.size()) { list.set(index, convertedValue); } else if (index >= list.size()) { for (int i = list.size(); i < index; i++) { try { list.add(null); } catch (NullPointerException ex) { throw new InvalidPropertyException(getRootClass(), this.nestedPath + propertyName, "Cannot set element with index " + index + " in List of size " + list.size() + ", accessed using property path '" + propertyName + "': List does not support filling up gaps with null elements"); } } list.add(convertedValue); } } else if (propValue instanceof Map) { PropertyDescriptor pd = getCachedIntrospectionResults().getPropertyDescriptor(actualName); Class mapKeyType = GenericCollectionTypeResolver.getMapKeyReturnType( pd.getReadMethod(), tokens.keys.length); Class mapValueType = GenericCollectionTypeResolver.getMapValueReturnType( pd.getReadMethod(), tokens.keys.length); Map map = (Map) propValue; // IMPORTANT: Do not pass full property name in here - property editors // must not kick in for map keys but rather only for map values. Object convertedMapKey = convertIfNecessary(null, null, key, mapKeyType, new PropertyTypeDescriptor(pd, new MethodParameter(pd.getReadMethod(), -1), mapKeyType)); Object oldValue = null; if (isExtractOldValueForEditor()) { oldValue = map.get(convertedMapKey); } // Pass full property name and old value in here, since we want full // conversion ability for map values. Object convertedMapValue = convertIfNecessary( propertyName, oldValue, pv.getValue(), mapValueType, new TypeDescriptor(new MethodParameter(pd.getReadMethod(), -1, tokens.keys.length + 1))); map.put(convertedMapKey, convertedMapValue); } else { throw new InvalidPropertyException(getRootClass(), this.nestedPath + propertyName, "Property referenced in indexed property path '" + propertyName + "' is neither an array nor a List nor a Map; returned value was [" + pv.getValue() + "]"); } } else { if("addStmt".equals(pv.getName())){ System.out.println("test setPropertyValues"); } PropertyDescriptor pd = pv.resolvedDescriptor; if (pd == null || !pd.getWriteMethod().getDeclaringClass().isInstance(this.object)) { pd = getCachedIntrospectionResults().getPropertyDescriptor(actualName); if (pd == null || pd.getWriteMethod() == null) { if (pv.isOptional()) { logger.debug("Ignoring optional value for property '" + actualName + "' - property not found on bean class [" + getRootClass().getName() + "]"); return; } else { PropertyMatches matches = PropertyMatches.forProperty(propertyName, getRootClass()); throw new NotWritablePropertyException( getRootClass(), this.nestedPath + propertyName, matches.buildErrorMessage(), matches.getPossibleMatches()); } } pv.getOriginalPropertyValue().resolvedDescriptor = pd; } Object oldValue = null; try { Object originalValue = pv.getValue(); Object valueToApply = originalValue; if (!Boolean.FALSE.equals(pv.conversionNecessary)) { if (pv.isConverted()) { valueToApply = pv.getConvertedValue(); } else { if (isExtractOldValueForEditor() && pd.getReadMethod() != null) { final Method readMethod = pd.getReadMethod(); if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers()) && !readMethod.isAccessible()) { if (System.getSecurityManager()!= null) { AccessController.doPrivileged(new PrivilegedAction<Object>() { public Object run() { readMethod.setAccessible(true); return null; } }); } else { readMethod.setAccessible(true); } } try { if (System.getSecurityManager() != null) { oldValue = AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() { public Object run() throws Exception { return readMethod.invoke(object); } }, acc); } else { oldValue = readMethod.invoke(object); } } catch (Exception ex) { if (ex instanceof PrivilegedActionException) { ex = ((PrivilegedActionException) ex).getException(); } if (logger.isDebugEnabled()) { logger.debug("Could not read previous value of property '" + this.nestedPath + propertyName + "'", ex); } } } valueToApply = convertForProperty(propertyName, oldValue, originalValue, pd); } pv.getOriginalPropertyValue().conversionNecessary = (valueToApply != originalValue); } final Method writeMethod = (pd instanceof GenericTypeAwarePropertyDescriptor ? ((GenericTypeAwarePropertyDescriptor) pd).getWriteMethodForActualAccess() : pd.getWriteMethod()); if (!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers()) && !writeMethod.isAccessible()) { if (System.getSecurityManager()!= null) { AccessController.doPrivileged(new PrivilegedAction<Object>() { public Object run() { writeMethod.setAccessible(true); return null; } }); } else { writeMethod.setAccessible(true); } } final Object value = valueToApply; if (System.getSecurityManager() != null) { try { AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() { public Object run() throws Exception { writeMethod.invoke(object, value); return null; } }, acc); } catch (PrivilegedActionException ex) { throw ex.getException(); } } else { writeMethod.invoke(this.object, value); } } catch (TypeMismatchException ex) { throw ex; } catch (InvocationTargetException ex) { PropertyChangeEvent propertyChangeEvent = new PropertyChangeEvent(this.rootObject, this.nestedPath + propertyName, oldValue, pv.getValue()); if (ex.getTargetException() instanceof ClassCastException) { throw new TypeMismatchException(propertyChangeEvent, pd.getPropertyType(), ex.getTargetException()); } else { throw new MethodInvocationException(propertyChangeEvent, ex.getTargetException()); } } catch (Exception ex) { PropertyChangeEvent pce = new PropertyChangeEvent(this.rootObject, this.nestedPath + propertyName, oldValue, pv.getValue()); throw new MethodInvocationException(pce, ex); } } }
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