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package com.fasterxml.jackson.databind.jsontype;
import java.io.IOException;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.databind.DatabindContext;
import com.fasterxml.jackson.databind.JavaType;
/**
* Interface that defines standard API for converting types
* to type identifiers and vice versa. Used by type resolvers
* ({@link com.fasterxml.jackson.databind.jsontype.TypeSerializer},
* {@link com.fasterxml.jackson.databind.jsontype.TypeDeserializer}) for converting
* between type and matching id; id is stored in JSON and needed for
* creating instances of proper subtypes when deserializing values.
*
* NOTE: it is strongly recommended that developers always extend
* abstract base class {@link com.fasterxml.jackson.databind.jsontype.impl.TypeIdResolverBase}
* instead of directly implementing this interface; this helps prevent
* breakage in case new methds need to be added in this interface (something
* we try to avoid doing; but which may be necessary in some cases).
*/
public interface TypeIdResolver
{
/*
/**********************************************************
/* Initialization/configuration methods
/**********************************************************
*/
/**
* Method that will be called once before any type resolution calls;
* used to initialize instance with configuration. This is necessary
* since instances may be created via reflection, without ability to
* call specific constructor to pass in configuration settings.
*
* @param baseType Base type for which this id resolver instance is
* used
*/
public void init(JavaType baseType);
/*
/**********************************************************
/* Conversions between types and type ids
/**********************************************************
*/
/**
* Method called to serialize type of the type of given value
* as a String to include in serialized JSON content.
*/
public String idFromValue(Object value);
/**
* Alternative method used for determining type from combination of
* value and type, using suggested type (that serializer provides)
* and possibly value of that type. Most common implementation will
* use suggested type as is.
*/
public String idFromValueAndType(Object value, Class suggestedType);
/**
* Method that can be called to figure out type id to use for instances
* of base type (declared type of property). This is usually only used
* for fallback handling, for cases where real type information is not
* available for some reason.
*/
public String idFromBaseType();
/**
* Method called to resolve type from given type identifier.
*
* @since 2.5 (throws clause added in 2.8)
*/
public JavaType typeFromId(DatabindContext context, String id) throws IOException;
/**
* Method called for error-reporting and diagnostics purposes.
*
* @since 2.7 -- but since 2.5 has existed in {@link com.fasterxml.jackson.databind.jsontype.impl.TypeIdResolverBase}
*/
public String getDescForKnownTypeIds();
/*
/**********************************************************
/* Accessors for metadata
/**********************************************************
*/
/**
* Accessor for mechanism that this resolver uses for determining
* type id from type. Mostly informational; not required to be called
* or used.
*/
public JsonTypeInfo.Id getMechanism();
}