Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Databind Source Code files are provided in the source packge (jackson-databind-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Databind Source Code below:

⏎ com/fasterxml/jackson/databind/jsontype/TypeIdResolver.java

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.
 *<p>
 * NOTE: it is <b>strongly</b> 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();
}

⏎ com/fasterxml/jackson/databind/jsontype/TypeIdResolver.java

Or download all of them as a single archive file:

File name: jackson-databind-2.14.0-sources.jar
File size: 1187952 bytes
Release date: 2022-11-05
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