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/type/ResolvedRecursiveType.java

package com.fasterxml.jackson.databind.type;

import com.fasterxml.jackson.databind.JavaType;

/**
 * Internal placeholder type used for self-references.
 *
 * @since 2.7
 */
public class ResolvedRecursiveType extends TypeBase
{
    private static final long serialVersionUID = 1L;

    protected JavaType _referencedType;

    public ResolvedRecursiveType(Class<?> erasedType, TypeBindings bindings) {
        super(erasedType, bindings, null, null, 0, null, null, false);
    }

    public void setReference(JavaType ref)
    {
        // sanity check; should not be called multiple times
        if (_referencedType != null) {
            throw new IllegalStateException("Trying to re-set self reference; old value = "+_referencedType+", new = "+ref);
        }
        _referencedType = ref;
    }
   
    @Override
    public JavaType getSuperClass() {
        if (_referencedType != null) {
            return _referencedType.getSuperClass();
        }
        return super.getSuperClass();
    }

    public JavaType getSelfReferencedType() { return _referencedType; }

    // 23-Jul-2019, tatu: [databind#2331] Need to also delegate this...
    @Override
    public TypeBindings getBindings() {
        if (_referencedType != null) { // `null` before resolution [databind#2395]
            return _referencedType.getBindings();
        }
        return super.getBindings();
    }

    @Override
    public StringBuilder getGenericSignature(StringBuilder sb) {
        // 30-Oct-2019, tatu: Alas, need to break recursion, otherwise we'll
        //    end up in StackOverflowError... two choices; '?' for "not known",
        //    or erased signature.
        if (_referencedType != null) {
//            return _referencedType.getGenericSignature(sb);
            return _referencedType.getErasedSignature(sb);
        }
        return sb.append("?");
    }

    @Override
    public StringBuilder getErasedSignature(StringBuilder sb) {
        if (_referencedType != null) {
            return _referencedType.getErasedSignature(sb);
        }
        return sb;
    }

    @Override
    public JavaType withContentType(JavaType contentType) {
        return this;
    }
    
    @Override
    public JavaType withTypeHandler(Object h) {
        return this;
    }

    @Override
    public JavaType withContentTypeHandler(Object h) {
        return this;
    }

    @Override
    public JavaType withValueHandler(Object h) {
        return this;
    }

    @Override
    public JavaType withContentValueHandler(Object h) {
        return this;
    }

    @Override
    public JavaType withStaticTyping() {
        return this;
    }

    @Deprecated // since 2.7
    @Override
    protected JavaType _narrow(Class<?> subclass) {
        return this;
    }

    @Override
    public JavaType refine(Class<?> rawType, TypeBindings bindings,
            JavaType superClass, JavaType[] superInterfaces) {
        return null;
    }

    @Override
    public boolean isContainerType() {
        return false;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder(40)
                .append("[recursive type; ");
        if (_referencedType == null) {
            sb.append("UNRESOLVED");
        } else {
            // [databind#1301]: Typically resolves to a loop so short-cut
            //   and only include type-erased class
            sb.append(_referencedType.getRawClass().getName());
        }
        return sb.toString();
    }

    @Override
    public boolean equals(Object o) {
        if (o == this) return true;
        if (o == null) return false;
        if (o.getClass() == getClass()) {
            // 16-Jun-2017, tatu: as per [databind#1658], cannot do recursive call since
            //    there is likely to be a cycle...

            // but... true or false?
            return false;
            
            /*
            // Do NOT ever match unresolved references
            if (_referencedType == null) {
                return false;
            }
            return (o.getClass() == getClass()
                    && _referencedType.equals(((ResolvedRecursiveType) o).getSelfReferencedType()));
                    */
        }
        return false;
    }
}

⏎ com/fasterxml/jackson/databind/type/ResolvedRecursiveType.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
Download 

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