Spring之BeanWrapper

作用

BeanWrapper接口和它的實作BeanWrapperImpl是整個Spring架構最基本的類。它們利用反射機制（Reflection）和JavaBeans的标準提供一些對Java類屬性的操作。其中最重要的操作是資料類型的轉換和嵌套屬性的引用（這使人聯想起BeanUtils,OGNL和JSTL EL）。

源碼

public interface BeanWrapper extends ConfigurablePropertyAccessor {

	/**
	 * Specify a limit for array and collection auto-growing.
	 * <p>Default is unlimited on a plain BeanWrapper.
	 * @since 4.1
	 */
	void setAutoGrowCollectionLimit(int autoGrowCollectionLimit);

	/**
	 * Return the limit for array and collection auto-growing.
	 * @since 4.1
	 */
	int getAutoGrowCollectionLimit();

	/**
	 * Return the bean instance wrapped by this object, if any.
	 * @return the bean instance, or {@code null} if none set
	 */
	Object getWrappedInstance();

	/**
	 * Return the type of the wrapped JavaBean object.
	 * @return the type of the wrapped bean instance,
	 * or {@code null} if no wrapped object has been set
	 */
	Class<?> getWrappedClass();

	/**
	 * Obtain the PropertyDescriptors for the wrapped object
	 * (as determined by standard JavaBeans introspection).
	 * @return the PropertyDescriptors for the wrapped object
	 */
	PropertyDescriptor[] getPropertyDescriptors();

	/**
	 * Obtain the property descriptor for a specific property
	 * of the wrapped object.
	 * @param propertyName the property to obtain the descriptor for
	 * (may be a nested path, but no indexed/mapped property)
	 * @return the property descriptor for the specified property
	 * @throws InvalidPropertyException if there is no such property
	 */
	PropertyDescriptor getPropertyDescriptor(String propertyName) throws InvalidPropertyException;

}