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/impl/MinimalClassNameIdResolver.java

package com.fasterxml.jackson.databind.jsontype.impl;

import java.io.IOException;

import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.databind.DatabindContext;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.jsontype.PolymorphicTypeValidator;
import com.fasterxml.jackson.databind.type.TypeFactory;

public class MinimalClassNameIdResolver
    extends ClassNameIdResolver
{
    /**
     * Package name of the base class, to be used for determining common
     * prefix that can be omitted from included type id.
     * Does not include the trailing dot.
     */
    protected final String _basePackageName;

    /**
     * Same as {@link #_basePackageName}, but includes trailing dot.
     */
    protected final String _basePackagePrefix;

    protected MinimalClassNameIdResolver(JavaType baseType, TypeFactory typeFactory,
            PolymorphicTypeValidator ptv)
    {
        super(baseType, typeFactory, ptv);
        String base = baseType.getRawClass().getName();
        int ix = base.lastIndexOf('.');
        if (ix < 0) { // can this ever occur?
            _basePackageName = "";
            _basePackagePrefix = ".";
        } else {
            _basePackagePrefix = base.substring(0, ix+1);
            _basePackageName = base.substring(0, ix);
        }
    }

    public static MinimalClassNameIdResolver construct(JavaType baseType, MapperConfig<?> config,
            PolymorphicTypeValidator ptv) {
        return new MinimalClassNameIdResolver(baseType, config.getTypeFactory(), ptv);
    }

    @Override
    public JsonTypeInfo.Id getMechanism() { return JsonTypeInfo.Id.MINIMAL_CLASS; }
    
    @Override
    public String idFromValue(Object value)
    {
        String n = value.getClass().getName();
        if (n.startsWith(_basePackagePrefix)) {
            // note: we will leave the leading dot in there
            return n.substring(_basePackagePrefix.length()-1);
        }
        return n;
    }

    @Override
    protected JavaType _typeFromId(String id, DatabindContext ctxt) throws IOException
    {
        if (id.startsWith(".")) {
            StringBuilder sb = new StringBuilder(id.length() + _basePackageName.length());
            if  (_basePackageName.isEmpty()) {
                // no package; must remove leading '.' from id
                sb.append(id.substring(1));
            } else {
                // otherwise just concatenate package, with leading-dot-partial name
                sb.append(_basePackageName).append(id);
            }
            id = sb.toString();
        }
        return super._typeFromId(id, ctxt);
    }
}

⏎ com/fasterxml/jackson/databind/jsontype/impl/MinimalClassNameIdResolver.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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