Package org.springframework.data.convert

Interface PropertyValueConverter<DV,SV,C extends ValueConversionContext<? extends PersistentProperty<?>>>

Type Parameters:

DV - domain-specific type.

SV - store-native type.

C - the store specific conversion context.

All Known Implementing Classes:

PropertyValueConverter.FunctionPropertyValueConverter, PropertyValueConverter.ObjectToObjectPropertyValueConverter

public interface PropertyValueConverter<DV,SV,C extends ValueConversionContext<? extends PersistentProperty<?>>>

PropertyValueConverter provides a symmetric way of converting certain properties from domain to store-specific values.

A PropertyValueConverter is, other than a ReadingConverter or WritingConverter, only applied to special annotated fields which allows a fine-grained conversion of certain values within a specific context.

Converter methods are called with non-null values only and provide specific hooks for null value handling. readNull(ValueConversionContext) and writeNull(ValueConversionContext) methods are specifically designated to either retain null values or return a different value to indicate null values.

Since:

2.7

Author:

Christoph Strobl, Mark Paluch

See Also:

• ValueConversionContext
• PersistentProperty

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	PropertyValueConverter.FunctionPropertyValueConverter<DV,SV,P extends PersistentProperty<P>>	A PropertyValueConverter that delegates conversion to the given BiFunctions.
static enum	PropertyValueConverter.ObjectToObjectPropertyValueConverter	No-op PropertyValueConverter implementation.

Method Summary

Modifier and Type	Method	Description
@Nullable DV	read(SV value, C context)	Convert the given store specific value into it's domain value representation.
default @Nullable DV	readNull(C context)	Convert the given null value from the store into its domain value representation.
@Nullable SV	write(DV value, C context)	Convert the given domain-specific value into it's native store representation.
default @Nullable SV	writeNull(C context)	Convert the given null value from the domain model into it's native store representation.

Method Details

read

@Nullable DV read(SV value,
 C context)

Convert the given store specific value into it's domain value representation. Typically, a read operation.

Parameters:

value - value to read.

context - ValueConversionContext containing store-specific metadata used in the value conversion; never null.

Returns:

the converted value. Can be null.

readNull

default @Nullable DV readNull(C context)

Convert the given null value from the store into its domain value representation. Typically, a read operation. Returns null by default.

Parameters:

context - ValueConversionContext containing store-specific metadata used in the value conversion; never null.

Returns:

the converted value. Can be null.

write

@Nullable SV write(DV value,
 C context)

Convert the given domain-specific value into it's native store representation. Typically, a write operation.

Parameters:

value - value to write; can be null.

context - ValueConversionContext containing store-specific metadata used in the value conversion; never null.

Returns:

the converted value. Can be null.

writeNull

default @Nullable SV writeNull(C context)

Convert the given null value from the domain model into it's native store representation. Typically, a write operation. Returns null by default.

Parameters:

context - ValueConversionContext containing store-specific metadata used in the value conversion; never null.

Returns:

the converted value. Can be null.