org.springframework.core.convert.support
Class GenericConversionService

java.lang.Object
  extended by org.springframework.core.convert.support.GenericConversionService
All Implemented Interfaces:
ConversionService, ConverterRegistry
Direct Known Subclasses:
FormattingConversionService

public class GenericConversionService
extends Object
implements ConversionService, ConverterRegistry

Base ConversionService implementation suitable for use in most environments. Implements ConverterRegistry as registration API.

Since:
3.0
Author:
Keith Donald, Juergen Hoeller

Constructor Summary
GenericConversionService()
           
 
Method Summary
 void addConverter(Converter<?,?> converter)
          Add a plain converter to this registry.
 void addConverter(GenericConverter converter)
          Add a generic converter to this registry.
 void addConverterFactory(ConverterFactory<?,?> converterFactory)
          Add a ranged converter factory to this registry.
 boolean canConvert(Class<?> sourceType, Class<?> targetType)
          Returns true if objects of sourceType can be converted to targetType.
 boolean canConvert(TypeDescriptor sourceType, TypeDescriptor targetType)
          Returns true if objects of sourceType can be converted to the targetType.
<T> T
convert(Object source, Class<T> targetType)
          Convert the source to targetType.
 Object convert(Object source, TypeDescriptor sourceType, TypeDescriptor targetType)
          Convert the source to targetType.
protected  Object convertNullSource(TypeDescriptor sourceType, TypeDescriptor targetType)
          Template method to convert a null source.
protected  GenericConverter getConverter(TypeDescriptor sourceType, TypeDescriptor targetType)
          Hook method to lookup the converter for a given sourceType/targetType pair.
protected  GenericConverter getDefaultConverter(TypeDescriptor sourceType, TypeDescriptor targetType)
          Return the default converter if no converter is found for the given sourceType/targetType pair.
 void removeConvertible(Class<?> sourceType, Class<?> targetType)
          Remove any converters from sourceType to targetType.
 String toString()
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

GenericConversionService

public GenericConversionService()
Method Detail

addConverter

public void addConverter(Converter<?,?> converter)
Description copied from interface: ConverterRegistry
Add a plain converter to this registry.

Specified by:
addConverter in interface ConverterRegistry

addConverterFactory

public void addConverterFactory(ConverterFactory<?,?> converterFactory)
Description copied from interface: ConverterRegistry
Add a ranged converter factory to this registry.

Specified by:
addConverterFactory in interface ConverterRegistry

addConverter

public void addConverter(GenericConverter converter)
Description copied from interface: ConverterRegistry
Add a generic converter to this registry.

Specified by:
addConverter in interface ConverterRegistry

removeConvertible

public void removeConvertible(Class<?> sourceType,
                              Class<?> targetType)
Description copied from interface: ConverterRegistry
Remove any converters from sourceType to targetType.

Specified by:
removeConvertible in interface ConverterRegistry
Parameters:
sourceType - the source type
targetType - the target type

canConvert

public boolean canConvert(Class<?> sourceType,
                          Class<?> targetType)
Description copied from interface: ConversionService
Returns true if objects of sourceType can be converted to targetType.

Specified by:
canConvert in interface ConversionService
Parameters:
sourceType - the source type to convert from (required)
targetType - the target type to convert to (required)
Returns:
true if a conversion can be performed, false if not

convert

public <T> T convert(Object source,
                     Class<T> targetType)
Description copied from interface: ConversionService
Convert the source to targetType.

Specified by:
convert in interface ConversionService
Parameters:
source - the source object to convert (may be null)
targetType - the target type to convert to (required)
Returns:
the converted object, an instance of targetType

canConvert

public boolean canConvert(TypeDescriptor sourceType,
                          TypeDescriptor targetType)
Description copied from interface: ConversionService
Returns true if objects of sourceType can be converted to the targetType. The TypeDescriptors provide additional context about the field locations where conversion would occur, often object property locations. This flavor of the canConvert operation exists mainly for use by a general purpose data mapping framework, and not for use by user code.

Specified by:
canConvert in interface ConversionService
Parameters:
sourceType - context about the source type to convert from (required)
targetType - context about the target type to convert to (required)
Returns:
true if a conversion can be performed between the source and target types, false if not

convert

public Object convert(Object source,
                      TypeDescriptor sourceType,
                      TypeDescriptor targetType)
Description copied from interface: ConversionService
Convert the source to targetType. The TypeDescriptors provide additional context about the field locations where conversion will occur, often object property locations. This flavor of the convert operation exists mainly for use by a general purpose data mapping framework, and not for use by user code.

Specified by:
convert in interface ConversionService
Parameters:
source - the source object to convert (may be null)
sourceType - context about the source type converting from (required)
targetType - context about the target type to convert to (required)
Returns:
the converted object, an instance of targetType

toString

public String toString()
Overrides:
toString in class Object

convertNullSource

protected Object convertNullSource(TypeDescriptor sourceType,
                                   TypeDescriptor targetType)
Template method to convert a null source.

Default implementation returns null. Throws a ConversionFailedException if the targetType is a primitive type, as null cannot be assigned to a primitive type. Subclasses may override to return custom null objects for specific target types.

Parameters:
sourceType - the sourceType to convert from
targetType - the targetType to convert to
Returns:
the converted null object

getConverter

protected GenericConverter getConverter(TypeDescriptor sourceType,
                                        TypeDescriptor targetType)
Hook method to lookup the converter for a given sourceType/targetType pair.

First queries this ConversionService's converter cache. On a cache miss, then performs an exhaustive search for a matching converter. If no converter matches, returns the default converter. Subclasses may override.

Parameters:
sourceType - the source type to convert from
targetType - the target type to convert to
Returns:
the generic converter that will perform the conversion, or null if no suitable converter was found
See Also:
getDefaultConverter(TypeDescriptor, TypeDescriptor)

getDefaultConverter

protected GenericConverter getDefaultConverter(TypeDescriptor sourceType,
                                               TypeDescriptor targetType)
Return the default converter if no converter is found for the given sourceType/targetType pair. Returns a NO_OP Converter if the sourceType is assignable to the targetType. Returns null otherwise, indicating no suitable converter could be found. Subclasses may override.

Parameters:
sourceType - the source type to convert from
targetType - the target type to convert to
Returns:
the default generic converter that will perform the conversion