beanwrapperimpl.java

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		}
		return null;
	}

	public boolean isReadableProperty(String propertyName) {
		try {
			PropertyDescriptor pd = getPropertyDescriptorInternal(propertyName);
			if (pd != null) {
				if (pd.getReadMethod() != null) {
					return true;
				}
			}
			else {
				// Maybe an indexed/mapped property...
				getPropertyValue(propertyName);
				return true;
			}
		}
		catch (InvalidPropertyException ex) {
			// Cannot be evaluated, so can't be readable.
		}
		return false;
	}

	public boolean isWritableProperty(String propertyName) {
		try {
			PropertyDescriptor pd = getPropertyDescriptorInternal(propertyName);
			if (pd != null) {
				if (pd.getWriteMethod() != null) {
					return true;
				}
			}
			else {
				// Maybe an indexed/mapped property...
				getPropertyValue(propertyName);
				return true;
			}
		}
		catch (InvalidPropertyException ex) {
			// Cannot be evaluated, so can't be writable.
		}
		return false;
	}


	//---------------------------------------------------------------------
	// Implementation of TypeConverter interface
	//---------------------------------------------------------------------

	/**
	 * @deprecated in favor of <code>convertIfNecessary</code>
	 * @see #convertIfNecessary(Object, Class)
	 */
	public Object doTypeConversionIfNecessary(Object value, Class requiredType) throws TypeMismatchException {
		return convertIfNecessary(value, requiredType, null);
	}

	public Object convertIfNecessary(Object value, Class requiredType) throws TypeMismatchException {
		return convertIfNecessary(value, requiredType, null);
	}

	public Object convertIfNecessary(
			Object value, Class requiredType, MethodParameter methodParam) throws TypeMismatchException {
		try {
			return this.typeConverterDelegate.convertIfNecessary(value, requiredType, methodParam);
		}
		catch (IllegalArgumentException ex) {
			throw new TypeMismatchException(value, requiredType, ex);
		}
	}

	/**
	 * Convert the given value for the specified property to the latter's type.
	 * <p>This method is only intended for optimizations in a BeanFactory.
	 * Use the <code>convertIfNecessary</code> methods for programmatic conversion.
	 * @param value the value to convert
	 * @param propertyName the target property
	 * (note that nested or indexed properties are not supported here)
	 * @return the new value, possibly the result of type conversion
	 * @throws TypeMismatchException if type conversion failed
	 */
	public Object convertForProperty(Object value, String propertyName) throws TypeMismatchException {
		PropertyDescriptor pd = this.cachedIntrospectionResults.getPropertyDescriptor(propertyName);
		if (pd == null) {
			throw new InvalidPropertyException(getRootClass(), this.nestedPath + propertyName,
					"No property '" + propertyName + "' found");
		}
		try {
			return this.typeConverterDelegate.convertIfNecessary(null, value, pd);
		}
		catch (IllegalArgumentException ex) {
			PropertyChangeEvent pce =
					new PropertyChangeEvent(this.rootObject, this.nestedPath + propertyName, null, value);
			throw new TypeMismatchException(pce, pd.getPropertyType(), ex);
		}
	}


	//---------------------------------------------------------------------
	// Implementation methods
	//---------------------------------------------------------------------

	/**
	 * Get the last component of the path. Also works if not nested.
	 * @param bw BeanWrapper to work on
	 * @param nestedPath property path we know is nested
	 * @return last component of the path (the property on the target bean)
	 */
	private String getFinalPath(BeanWrapper bw, String nestedPath) {
		if (bw == this) {
			return nestedPath;
		}
		return nestedPath.substring(PropertyAccessorUtils.getLastNestedPropertySeparatorIndex(nestedPath) + 1);
	}

	/**
	 * Recursively navigate to return a BeanWrapper for the nested property path.
	 * @param propertyPath property property path, which may be nested
	 * @return a BeanWrapper for the target bean
	 */
	protected BeanWrapperImpl getBeanWrapperForPropertyPath(String propertyPath) {
		int pos = PropertyAccessorUtils.getFirstNestedPropertySeparatorIndex(propertyPath);
		// Handle nested properties recursively.
		if (pos > -1) {
			String nestedProperty = propertyPath.substring(0, pos);
			String nestedPath = propertyPath.substring(pos + 1);
			BeanWrapperImpl nestedBw = getNestedBeanWrapper(nestedProperty);
			return nestedBw.getBeanWrapperForPropertyPath(nestedPath);
		}
		else {
			return this;
		}
	}

	/**
	 * Retrieve a BeanWrapper for the given nested property.
	 * Create a new one if not found in the cache.
	 * <p>Note: Caching nested BeanWrappers is necessary now,
	 * to keep registered custom editors for nested properties.
	 * @param nestedProperty property to create the BeanWrapper for
	 * @return the BeanWrapper instance, either cached or newly created
	 */
	private BeanWrapperImpl getNestedBeanWrapper(String nestedProperty) {
		if (this.nestedBeanWrappers == null) {
			this.nestedBeanWrappers = new HashMap();
		}
		// Get value of bean property.
		PropertyTokenHolder tokens = getPropertyNameTokens(nestedProperty);
		String canonicalName = tokens.canonicalName;
		Object propertyValue = getPropertyValue(tokens);
		if (propertyValue == null) {
			throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + canonicalName);
		}

		// Lookup cached sub-BeanWrapper, create new one if not found.
		BeanWrapperImpl nestedBw = (BeanWrapperImpl) this.nestedBeanWrappers.get(canonicalName);
		if (nestedBw == null || nestedBw.getWrappedInstance() != propertyValue) {
			if (logger.isTraceEnabled()) {
				logger.trace("Creating new nested BeanWrapper for property '" + canonicalName + "'");
			}
			nestedBw = newNestedBeanWrapper(propertyValue, this.nestedPath + canonicalName + NESTED_PROPERTY_SEPARATOR);
			// Inherit all type-specific PropertyEditors.
			copyDefaultEditorsTo(nestedBw);
			copyCustomEditorsTo(nestedBw, canonicalName);
			this.nestedBeanWrappers.put(canonicalName, nestedBw);
		}
		else {
			if (logger.isTraceEnabled()) {
				logger.trace("Using cached nested BeanWrapper for property '" + canonicalName + "'");
			}
		}
		return nestedBw;
	}

	/**
	 * Create a new nested BeanWrapper instance.
	 * <p>Default implementation creates a BeanWrapperImpl instance.
	 * Can be overridden in subclasses to create a BeanWrapperImpl subclass.
	 * @param object object wrapped by this BeanWrapper
	 * @param nestedPath the nested path of the object
	 * @return the nested BeanWrapper instance
	 */
	protected BeanWrapperImpl newNestedBeanWrapper(Object object, String nestedPath) {
		return new BeanWrapperImpl(object, nestedPath, this);
	}

	/**
	 * Parse the given property name into the corresponding property name tokens.
	 * @param propertyName the property name to parse
	 * @return representation of the parsed property tokens
	 */
	private PropertyTokenHolder getPropertyNameTokens(String propertyName) {
		PropertyTokenHolder tokens = new PropertyTokenHolder();
		String actualName = null;
		List keys = new ArrayList(2);
		int searchIndex = 0;
		while (searchIndex != -1) {
			int keyStart = propertyName.indexOf(PROPERTY_KEY_PREFIX, searchIndex);
			searchIndex = -1;
			if (keyStart != -1) {
				int keyEnd = propertyName.indexOf(PROPERTY_KEY_SUFFIX, keyStart + PROPERTY_KEY_PREFIX.length());
				if (keyEnd != -1) {
					if (actualName == null) {
						actualName = propertyName.substring(0, keyStart);
					}
					String key = propertyName.substring(keyStart + PROPERTY_KEY_PREFIX.length(), keyEnd);
					if ((key.startsWith("'") && key.endsWith("'")) || (key.startsWith("\"") && key.endsWith("\""))) {
						key = key.substring(1, key.length() - 1);
					}
					keys.add(key);
					searchIndex = keyEnd + PROPERTY_KEY_SUFFIX.length();
				}
			}
		}
		tokens.actualName = (actualName != null ? actualName : propertyName);
		tokens.canonicalName = tokens.actualName;
		if (!keys.isEmpty()) {
			tokens.canonicalName +=
					PROPERTY_KEY_PREFIX +
					StringUtils.collectionToDelimitedString(keys, PROPERTY_KEY_SUFFIX + PROPERTY_KEY_PREFIX) +
					PROPERTY_KEY_SUFFIX;
			tokens.keys = StringUtils.toStringArray(keys);
		}
		return tokens;
	}


	//---------------------------------------------------------------------
	// Implementation of PropertyAccessor interface
	//---------------------------------------------------------------------

	public Object getPropertyValue(String propertyName) throws BeansException {
		BeanWrapperImpl nestedBw = getBeanWrapperForPropertyPath(propertyName);
		PropertyTokenHolder tokens = getPropertyNameTokens(getFinalPath(nestedBw, propertyName));
		return nestedBw.getPropertyValue(tokens);
	}

	private Object getPropertyValue(PropertyTokenHolder tokens) throws BeansException {
		String propertyName = tokens.canonicalName;
		String actualName = tokens.actualName;
		PropertyDescriptor pd = this.cachedIntrospectionResults.getPropertyDescriptor(actualName);
		if (pd == null || pd.getReadMethod() == null) {
			throw new NotReadablePropertyException(getRootClass(), this.nestedPath + propertyName);
		}
		Method readMethod = pd.getReadMethod();
		try {
			if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
				readMethod.setAccessible(true);
			}
			Object value = readMethod.invoke(this.object, (Object[]) null);
			if (tokens.keys != null) {
				// apply indexes and map keys
				for (int i = 0; i < tokens.keys.length; i++) {
					String key = tokens.keys[i];
					if (value == null) {
						throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + propertyName,
								"Cannot access indexed value of property referenced in indexed " +
								"property path '" + propertyName + "': returned null");
					}
					else if (value.getClass().isArray()) {
						value = Array.get(value, Integer.parseInt(key));
					}
					else if (value instanceof List) {
						List list = (List) value;
						value = list.get(Integer.parseInt(key));
					}
					else if (value instanceof Set) {
						// Apply index to Iterator in case of a Set.
						Set set = (Set) value;
						int index = Integer.parseInt(key);
						if (index < 0 || index >= set.size()) {
							throw new InvalidPropertyException(getRootClass(), this.nestedPath + propertyName,
									"Cannot get element with index " + index + " from Set of size " +
									set.size() + ", accessed using property path '" + propertyName + "'");
						}
						Iterator it = set.iterator();
						for (int j = 0; it.hasNext(); j++) {
							Object elem = it.next();
							if (j == index) {
								value = elem;
								break;
							}
						}
					}
					else if (value instanceof Map) {
						Map map = (Map) value;
						Class mapKeyType = null;
						if (JdkVersion.isAtLeastJava15()) {
							mapKeyType = GenericCollectionTypeResolver.getMapKeyReturnType(pd.getReadMethod(), i + 1);
						}
						// IMPORTANT: Do not pass full property name in here - property editors