io.micronaut.core.convert

Interface TypeConverter<S,T>

Type Parameters:

S - The source type

T - The target type

All Known Subinterfaces:

FormattingTypeConverter<S,T,A>

All Known Implementing Classes:

CorsOriginConverter, MultiValuesConverterFactory.AbstractConverterToMultiValues, MultiValuesConverterFactory.IterableToMultiValuesConverter, MultiValuesConverterFactory.MapToMultiValuesConverter, MultiValuesConverterFactory.MultiValuesToIterableConverter, MultiValuesConverterFactory.MultiValuesToMapConverter, MultiValuesConverterFactory.MultiValuesToObjectConverter, MultiValuesConverterFactory.ObjectToMultiValuesConverter, ReadableBytesTypeConverter, SameSiteConverter

@Indexed(value=TypeConverter.class)
public interface TypeConverter<S,T>

A type converter for converting from one type to another.

Implementations should be stateless, simple and thread safe. Type converters are often best defined as Java lambdas. You should NOT perform any overly complex, blocking or slow conversions in implementations of this interface.

If dependency injection is required, carefully consider what you inject. Databases and I/O bound interfaces are not good candidates. In addition, injecting dependencies that may trigger the evaluation of beans that depend on configuration will cause problems because all type converters have not been registered yet.

Since:

1.0

Author:

Graeme Rocher

Method Summary

Modifier and Type	Method and Description
default Optional<T>	convert(S object, Class<T> targetType) Converts from the given source object type to the target type.
Optional<T>	convert(S object, Class<T> targetType, ConversionContext context) Converts from the given source object type to the target type.
static <ST,TT> TypeConverter<ST,TT>	of(Class<ST> sourceType, Class<TT> targetType, Function<ST,TT> converter) Creates a new TypeConverter for the give source type, target type and conversion function.

Method Detail

convert

default Optional<T> convert(S object,
                            Class<T> targetType)

Converts from the given source object type to the target type.

Parameters:

object - The object type

targetType - The target type being converted to

Returns:

The converted type or empty if the conversion is not possible

convert

Optional<T> convert(S object,
                    Class<T> targetType,
                    ConversionContext context)

Converts from the given source object type to the target type. Implementers should take care to return Optional.empty() in case the object is not convertible by catching any necessary exceptions and failing gracefully.

Parameters:

object - The object type

targetType - The target type being converted to

context - The ConversionContext

Returns:

The converted type or empty if the conversion is not possible

of

static <ST,TT> TypeConverter<ST,TT> of(Class<ST> sourceType,
                                       Class<TT> targetType,
                                       Function<ST,TT> converter)

Creates a new TypeConverter for the give source type, target type and conversion function.

Type Parameters:

ST - The source generic type

TT - The target generic type

Parameters:

sourceType - The source type

targetType - The target type

converter - The converter function

Returns:

The converter instance