org.peaseplate.service
Interface ConversionService

All Known Implementing Classes:

DefaultConversionService

public interface ConversionService

The conversion service is responsible for converting values from one data type to another. The service can be enhances by adding ConversionInitializers to it.

Author:

Manfred Hantschel

Method Summary

void	add(java.lang.Class<? extends ConversionInitializer> initializerClass) Adds the conversion initializer specified by its class name to the service.
<SOURCE,TARGET> void	add(java.lang.Class<SOURCE> sourceType, java.lang.Class<TARGET> targetType, Conversion<SOURCE,TARGET> conversion) Adds a conversion from the specified source type to the specified target type to the service.
void	add(java.lang.ClassLoader... classLoaders) Scans the specified class loaders for conversion service definitions.
void	add(ConversionInitializer initializer) Adds the conversions in the conversion initializer to the service.
<SOURCE,TARGET> TARGET	convert(SOURCE value, java.lang.Class<TARGET> targetType) Converts the specified value to the specified target type.
<SOURCE,TARGET> TARGET	convey(SOURCE value, java.lang.Class<TARGET> targetType) Converts the specified value to the specified target type.
<SOURCE,TARGET> boolean	isConvertable(java.lang.Class<SOURCE> sourceType, java.lang.Class<TARGET> targetType) Returns true if there is a conversion rule defined for the specified source type and the specified target type.

Method Detail

add

void add(java.lang.ClassLoader... classLoaders)
         throws java.lang.IllegalArgumentException

Scans the specified class loaders for conversion service definitions. The definitions are located in a resource with the name "META-INF/services/org.peaseplate.service.ConversionService". The file contains class names of ConversionInitializers, one class name per line.

Parameters:

classLoaders - the class loaders

Throws:

java.lang.IllegalArgumentException - if a class could not be instantiated

add

void add(java.lang.Class<? extends ConversionInitializer> initializerClass)
         throws java.lang.IllegalArgumentException

Adds the conversion initializer specified by its class name to the service. The instance will be created immediately, passed to the add(ConversionInitializer) method and then thrown away.

Parameters:

initializerClass - the class

Throws:

java.lang.IllegalArgumentException - if the class could not be instantiated

add

void add(ConversionInitializer initializer)

Adds the conversions in the conversion initializer to the service. The initializer itself will not be stored and can be thrown away.

Parameters:

initializer - the initializer

add

<SOURCE,TARGET> void add(java.lang.Class<SOURCE> sourceType,
                         java.lang.Class<TARGET> targetType,
                         Conversion<SOURCE,TARGET> conversion)

Adds a conversion from the specified source type to the specified target type to the service.

Type Parameters:

SOURCE - the source type

TARGET - the target type

Parameters:

sourceType - the source type

targetType - the target type

conversion - the conversion

convey

<SOURCE,TARGET> TARGET convey(SOURCE value,
                              java.lang.Class<TARGET> targetType)
              throws ConversionException

Converts the specified value to the specified target type. If the value is null, it converts this value according to the conversion rule.

Type Parameters:

SOURCE - the source type

TARGET - the target type

Parameters:

value - the value, may be null

targetType - the target type

Returns:

the converted value

Throws:

ConversionException - if something went wrong during converting

convert

<SOURCE,TARGET> TARGET convert(SOURCE value,
                               java.lang.Class<TARGET> targetType)
               throws ConversionException

Converts the specified value to the specified target type. If the value is null, it returns null, and does not use the conversion rule.

Type Parameters:

SOURCE - the source type

TARGET - the target type

Parameters:

value - the value, may be null

targetType - the target type

Returns:

the converted value

Throws:

ConversionException - if something went wrong during converting

isConvertable

<SOURCE,TARGET> boolean isConvertable(java.lang.Class<SOURCE> sourceType,
                                      java.lang.Class<TARGET> targetType)

Returns true if there is a conversion rule defined for the specified source type and the specified target type.

Type Parameters:

SOURCE - the source type

TARGET - the target type

Parameters:

sourceType - the source type

targetType - the target type

Returns:

true if conversion rule is defined