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/*
* @(#)LazyInitializeConverter.java 5/19/2013
*
* Copyright 2002 - 2013 JIDE Software Inc. All rights reserved.
*/
package jidefx.utils.converter;
/**
* {@code LazyInitializeConverter} is an interface that can be implemented by any object converters to support lazy
* initialization.
*
* The first reason to use the lazy initialization is when the conversion logic requires the knowledge of the actual
* data type or the converter context.
*
* For example, for enum converter, we won't know how to convert a value until we know what the enum type is. We could
* register a converter for each enum type, but that's way too many. So in the ObjectConverterManager, we only have one
* entry for all enum types using registerConverter(Enum.class, new EnumConverter()). EnumConverter implements this
* LazyInitializeConverter. ObjectConverterManager will call the initialize method with the actual enum type when it
* sees a converter implementing LazyInitializeConverter. In the initialize method of EnumConverter, we will get all
* enum constants and save them as an array. When toString or fromString is called, we will look up in the array to do
* the conversion. By using this interface, we don't need to register a converter for each enum type.
*
* Another reason to use this interface is when the the converter takes time to create. So instead of initializing the
* logic up front in the constructor, you can put the expensive logic in this initialize method.
*/
public interface LazyInitializeConverter {
/**
* Initialize the converter. This method will be called by {@link ObjectConverterManager} in the getConverter
* method.
*
* @param clazz the actual data type.
* @param converterContext the actual converter context.
*/
void initialize(Class clazz, ConverterContext converterContext);
}