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/introspect/VisibilityChecker.java

package com.fasterxml.jackson.databind.introspect;

import java.lang.reflect.Field;
import java.lang.reflect.Member;
import java.lang.reflect.Method;


import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;

/**
 * Interface for object used for determine which property elements
 * (methods, fields, constructors) can be auto-detected, with respect
 * to their visibility modifiers.
 *<p>
 * Note on type declaration: funky recursive type is necessary to
 * support builder/fluent pattern.
 */
public interface VisibilityChecker<T extends VisibilityChecker<T>>
{
    // // Builder methods

    /**
     * Builder method that will return an instance that has same
     * settings as this instance has, except for values that
     * given annotation overrides.
     */
    public T with(JsonAutoDetect ann);

    /**
     * Method that can be used for merging default values from `this`
     * instance with specified overrides; and either return `this`
     * if overrides had no effect (that is, result would be equal),
     * or a new instance with merged visibility settings.
     *
     * @since 2.9
     */
    public T withOverrides(JsonAutoDetect.Value vis);

    /**
     * Builder method that will create and return an instance that has specified
     * {@link Visibility} value to use for all property elements.
     * Typical usage would be something like:
     *<pre>
     *  mapper.setVisibilityChecker(
     *     mapper.getVisibilityChecker().with(Visibility.NONE));
     *</pre>
     * (which would basically disable all auto-detection)
     */
    public T with(Visibility v);

    /**
     * Builder method that will create and return an instance that has specified
     * {@link Visibility} value to use for specified property.
     * Typical usage would be:
     *<pre>
     *  mapper.setVisibilityChecker(
     *     mapper.getVisibilityChecker().withVisibility(JsonMethod.FIELD, Visibility.ANY));
     *</pre>
     * (which would basically enable auto-detection for all member fields)
     */
    public T withVisibility(PropertyAccessor method, Visibility v);
    
    /**
     * Builder method that will return a checker instance that has
     * specified minimum visibility level for regular ("getXxx") getters.
     */
    public T withGetterVisibility(Visibility v);

    /**
     * Builder method that will return a checker instance that has
     * specified minimum visibility level for "is-getters" ("isXxx").
     */
    public T withIsGetterVisibility(Visibility v);
    
    /**
     * Builder method that will return a checker instance that has
     * specified minimum visibility level for setters.
     */
    public T withSetterVisibility(Visibility v);

    /**
     * Builder method that will return a checker instance that has
     * specified minimum visibility level for creator methods
     * (constructors, factory methods)
     */
    public T withCreatorVisibility(Visibility v);

    /**
     * Builder method that will return a checker instance that has
     * specified minimum visibility level for fields.
     */
    public T withFieldVisibility(Visibility v);
	
    // // Accessors
	
    /**
     * Method for checking whether given method is auto-detectable
     * as regular getter, with respect to its visibility (not considering
     * method signature or name, just visibility)
     */
    public boolean isGetterVisible(Method m);
    public boolean isGetterVisible(AnnotatedMethod m);

    /**
     * Method for checking whether given method is auto-detectable
     * as is-getter, with respect to its visibility (not considering
     * method signature or name, just visibility)
     */
    public boolean isIsGetterVisible(Method m);
    public boolean isIsGetterVisible(AnnotatedMethod m);
    
    /**
     * Method for checking whether given method is auto-detectable
     * as setter, with respect to its visibility (not considering
     * method signature or name, just visibility)
     */
    public boolean isSetterVisible(Method m);
    public boolean isSetterVisible(AnnotatedMethod m);

    /**
     * Method for checking whether given method is auto-detectable
     * as Creator, with respect to its visibility (not considering
     * method signature or name, just visibility)
     */
    public boolean isCreatorVisible(Member m);
    public boolean isCreatorVisible(AnnotatedMember m);

    /**
     * Method for checking whether given field is auto-detectable
     * as property, with respect to its visibility (not considering
     * method signature or name, just visibility)
     */
    public boolean isFieldVisible(Field f);
    public boolean isFieldVisible(AnnotatedField f);

    /*
    /********************************************************
    /* Standard implementation suitable for basic use
    /********************************************************
    */

   /**
    * Default standard implementation is purely based on visibility
    * modifier of given class members, and its configured minimum
    * levels.
    * Implemented using "builder" (or "Fluent") pattern, whereas instances
    * are immutable, and configuration is achieved by chainable factory
    * methods. As a result, type is declared is funky recursive generic
    * type, to allow for sub-classing of build methods with property type
    * co-variance.
    */
    public static class Std
        implements VisibilityChecker<Std>,
            java.io.Serializable
    {
        private static final long serialVersionUID = 1;

        /**
         * This is the canonical base instance, configured with default
         * visibility values
         */
        protected final static Std DEFAULT = new Std(
                Visibility.PUBLIC_ONLY, // getter
                Visibility.PUBLIC_ONLY, // is-getter
                Visibility.ANY, // setter
                Visibility.ANY, // creator -- legacy, to support single-arg ctors
                Visibility.PUBLIC_ONLY // field
                );

        /**
         * Alternate base settings used for JDK types: public visibility
         * required for everything
         *
         * @since 2.13
         */
        protected final static Std ALL_PUBLIC = new Std(
                Visibility.PUBLIC_ONLY, // getter
                Visibility.PUBLIC_ONLY, // is-getter
                Visibility.PUBLIC_ONLY, // setter
                Visibility.PUBLIC_ONLY, // creator (single-arg ctors)
                Visibility.PUBLIC_ONLY // field
        );

        protected final Visibility _getterMinLevel;
        protected final Visibility _isGetterMinLevel;
        protected final Visibility _setterMinLevel;
        protected final Visibility _creatorMinLevel;
        protected final Visibility _fieldMinLevel;

        /**
         * @return Instance with default settings: "public" for getters/is-getters,
         *    fields; "any" for setters and legacy 1-arg constructors
         */
        public static Std defaultInstance() { return DEFAULT; }

        /**
         * @return Instance with all visibility levels set to "public"
         *
         * @since 2.13
         */
        public static Std allPublicInstance() { return ALL_PUBLIC; }
        
        /**
         * Constructor used for building instance that has minumum visibility
         * levels as indicated by given annotation instance
         * 
         * @param ann Annotations to use for determining minimum visibility levels
         */
        public Std(JsonAutoDetect ann)
        {
            // let's combine checks for enabled/disabled, with minimum level checks:
            _getterMinLevel = ann.getterVisibility();
            _isGetterMinLevel = ann.isGetterVisibility();
            _setterMinLevel = ann.setterVisibility();
            _creatorMinLevel = ann.creatorVisibility();
            _fieldMinLevel = ann.fieldVisibility();
        }

        /**
         * Constructor that allows directly specifying minimum visibility levels to use
         */
        public Std(Visibility getter, Visibility isGetter, Visibility setter,
                Visibility creator, Visibility field)
        {
            _getterMinLevel = getter;
            _isGetterMinLevel = isGetter;
            _setterMinLevel = setter;
            _creatorMinLevel = creator;
            _fieldMinLevel = field;
        }

        /**
         * Constructor that will assign given visibility value for all
         * properties.
         * 
         * @param v level to use for all property types
         */
        public Std(Visibility v)
        {
            // typically we shouldn't get this value; but let's handle it if we do:
            if (v == Visibility.DEFAULT) {
                _getterMinLevel = DEFAULT._getterMinLevel;
                _isGetterMinLevel = DEFAULT._isGetterMinLevel;
                _setterMinLevel = DEFAULT._setterMinLevel;
                _creatorMinLevel = DEFAULT._creatorMinLevel;
                _fieldMinLevel = DEFAULT._fieldMinLevel;
            } else {
                _getterMinLevel = v;
                _isGetterMinLevel = v;
                _setterMinLevel = v;
                _creatorMinLevel = v;
                _fieldMinLevel = v;
            }
        }

        /**
         * @since 2.9
         */
        public static Std construct(JsonAutoDetect.Value vis) {
            return DEFAULT.withOverrides(vis);
        }

        /*
        /********************************************************
        /* Builder/fluent methods for instantiating configured
        /* instances
        /********************************************************
         */

        protected Std _with(Visibility g, Visibility isG, Visibility s,
                Visibility cr, Visibility f) {
            if ((g == _getterMinLevel)
                    && (isG == _isGetterMinLevel)
                    && (s == _setterMinLevel)
                    && (cr == _creatorMinLevel)
                    && (f == _fieldMinLevel)
                    ) {
                return this;
            }
            return new Std(g, isG, s, cr, f);
        }

        @Override
        public Std with(JsonAutoDetect ann)
        {
            Std curr = this;
            if (ann != null) {
                return _with(
                        _defaultOrOverride(_getterMinLevel, ann.getterVisibility()),
                        _defaultOrOverride(_isGetterMinLevel, ann.isGetterVisibility()),
                        _defaultOrOverride(_setterMinLevel, ann.setterVisibility()),
                        _defaultOrOverride(_creatorMinLevel, ann.creatorVisibility()),
                        _defaultOrOverride(_fieldMinLevel, ann.fieldVisibility())
                        );
            }
            return curr;
        }

        @Override // since 2.9
        public Std withOverrides(JsonAutoDetect.Value vis)
        {
            Std curr = this;
            if (vis != null) {
                return _with(
                        _defaultOrOverride(_getterMinLevel, vis.getGetterVisibility()),
                        _defaultOrOverride(_isGetterMinLevel, vis.getIsGetterVisibility()),
                        _defaultOrOverride(_setterMinLevel, vis.getSetterVisibility()),
                        _defaultOrOverride(_creatorMinLevel, vis.getCreatorVisibility()),
                        _defaultOrOverride(_fieldMinLevel, vis.getFieldVisibility())
                        );
            }
            return curr;
        }

        private Visibility _defaultOrOverride(Visibility defaults, Visibility override) {
            if (override == Visibility.DEFAULT) {
                return defaults;
            }
            return override;
        }

        @Override
        public Std with(Visibility v)
        {
            if (v == Visibility.DEFAULT) {
                return DEFAULT;
            }
            return new Std(v);
        }

        @Override
        public Std withVisibility(PropertyAccessor method, Visibility v)
        {
            switch (method) {
            case GETTER:
                return withGetterVisibility(v);
            case SETTER:
                return withSetterVisibility(v);
            case CREATOR:
                return withCreatorVisibility(v);
            case FIELD:
                return withFieldVisibility(v);
            case IS_GETTER:
                return withIsGetterVisibility(v);
            case ALL:
                return with(v);
            //case NONE:
            default:
                // break;
                return this;
            }
        }
	
        @Override
        public Std withGetterVisibility(Visibility v) {
            if (v == Visibility.DEFAULT) v = DEFAULT._getterMinLevel;
            if (_getterMinLevel == v) return this;
            return new Std(v, _isGetterMinLevel, _setterMinLevel, _creatorMinLevel, _fieldMinLevel);
        }

        @Override
        public Std withIsGetterVisibility(Visibility v) {
            if (v == Visibility.DEFAULT) v = DEFAULT._isGetterMinLevel;
            if (_isGetterMinLevel == v) return this;
            return new Std(_getterMinLevel, v, _setterMinLevel, _creatorMinLevel, _fieldMinLevel);
        }

        @Override
        public Std withSetterVisibility(Visibility v) {
            if (v == Visibility.DEFAULT) v = DEFAULT._setterMinLevel;
            if (_setterMinLevel == v) return this;
            return new Std(_getterMinLevel, _isGetterMinLevel, v, _creatorMinLevel, _fieldMinLevel);
        }

        @Override
        public Std withCreatorVisibility(Visibility v) {
            if (v == Visibility.DEFAULT) v = DEFAULT._creatorMinLevel;
            if (_creatorMinLevel == v) return this;
            return new Std(_getterMinLevel, _isGetterMinLevel, _setterMinLevel, v, _fieldMinLevel);
        }

        @Override
        public Std withFieldVisibility(Visibility v) {
            if (v == Visibility.DEFAULT)  v = DEFAULT._fieldMinLevel;
            if (_fieldMinLevel == v) return this;
            return new Std(_getterMinLevel, _isGetterMinLevel, _setterMinLevel, _creatorMinLevel, v);
        }

        /*
        /********************************************************
        /* Public API impl
        /********************************************************
         */

        @Override
        public boolean isCreatorVisible(Member m) {
            return _creatorMinLevel.isVisible(m);
        }

        @Override
        public boolean isCreatorVisible(AnnotatedMember m) {
            return isCreatorVisible(m.getMember());
        }

        @Override
        public boolean isFieldVisible(Field f) {
            return _fieldMinLevel.isVisible(f);
        }

        @Override
        public boolean isFieldVisible(AnnotatedField f) {
            return isFieldVisible(f.getAnnotated());
        }

        @Override
        public boolean isGetterVisible(Method m) {
            return _getterMinLevel.isVisible(m);
        }

        @Override
        public boolean isGetterVisible(AnnotatedMethod m) {
             return isGetterVisible(m.getAnnotated());
        }
    
        @Override
        public boolean isIsGetterVisible(Method m) {
            return _isGetterMinLevel.isVisible(m);
        }    
    
        @Override
        public boolean isIsGetterVisible(AnnotatedMethod m) {
            return isIsGetterVisible(m.getAnnotated());
        }
    
        @Override
        public boolean isSetterVisible(Method m) {
            return _setterMinLevel.isVisible(m);
        }
        
        @Override
        public boolean isSetterVisible(AnnotatedMethod m) {
            return isSetterVisible(m.getAnnotated());
        }

        /*
        /********************************************************
        /* Standard methods
        /********************************************************
         */
    
        @Override
        public String toString() {
            return String.format("[Visibility: getter=%s,isGetter=%s,setter=%s,creator=%s,field=%s]",
                    _getterMinLevel, _isGetterMinLevel, _setterMinLevel, _creatorMinLevel, _fieldMinLevel);
        }
    }
}

⏎ com/fasterxml/jackson/databind/introspect/VisibilityChecker.java

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