jidefx.utils.converter

Interface LazyInitializeConverter

All Known Implementing Classes:

EnumConverter

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

public interface LazyInitializeConverter

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.

Method Summary

Modifier and Type	Method and Description
void	initialize(java.lang.Class<?> clazz, ConverterContext converterContext) Initialize the converter.

Method Detail

initialize

void initialize(java.lang.Class<?> clazz,
                ConverterContext converterContext)

Initialize the converter. This method will be called by ObjectConverterManager in the getConverter method.

Parameters:

clazz - the actual data type.

converterContext - the actual converter context.