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/ser/BeanSerializerModifier.java

package com.fasterxml.jackson.databind.ser;

import java.util.List;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.DeserializerFactory;
import com.fasterxml.jackson.databind.type.*;

/**
 * Abstract class that defines API for objects that can be registered (for {@link BeanSerializerFactory}
 * to participate in constructing {@link BeanSerializer} instances.
 * This is typically done by modules that want alter some aspects of serialization
 * process; and is preferable to sub-classing of {@link BeanSerializerFactory}.
 *<p>
 * Sequence in which callback methods are called is as follows:
 * <ol>
 *  <li>After factory has collected tentative set of properties (instances of
 *     <code>BeanPropertyWriter</code>) is sent for modification via
 *     {@link #changeProperties}. Changes can include removal, addition and
 *     replacement of suggested properties.
 *  <li>Resulting set of properties are ordered (sorted) by factory, as per
 *     configuration, and then {@link #orderProperties} is called to allow
 *     modifiers to alter ordering.
 *  <li>After all bean properties and related information is accumulated,
 *     {@link #updateBuilder} is called with builder, to allow builder state
 *     to be modified (including possibly replacing builder itself if necessary)
 *  <li>Once all bean information has been determined,
 *     factory creates default {@link BeanSerializer} instance and passes
 *     it to modifiers using {@link #modifySerializer}, for possible
 *     modification or replacement (by any {@link com.fasterxml.jackson.databind.JsonSerializer} instance)
 * </ol>
 *<p>
 * Default method implementations are "no-op"s, meaning that methods are implemented
 * but have no effect.
 */
public abstract class BeanSerializerModifier
{
    /**
     * Method called by {@link BeanSerializerFactory} with tentative set
     * of discovered properties.
     * Implementations can add, remove or replace any of passed properties.
     *
     * Properties <code>List</code> passed as argument is modifiable, and returned List must
     * likewise be modifiable as it may be passed to multiple registered
     * modifiers.
     */
    public List<BeanPropertyWriter> changeProperties(SerializationConfig config,
            BeanDescription beanDesc, List<BeanPropertyWriter> beanProperties) {
        return beanProperties;
    }

    /**
     * Method called by {@link BeanSerializerFactory} with set of properties
     * to serialize, in default ordering (based on defaults as well as 
     * possible type annotations).
     * Implementations can change ordering any way they like.
     *
     * Properties <code>List</code> passed as argument is modifiable, and returned List must
     * likewise be modifiable as it may be passed to multiple registered
     * modifiers.
     */
    public List<BeanPropertyWriter> orderProperties(SerializationConfig config,
            BeanDescription beanDesc, List<BeanPropertyWriter> beanProperties) {
        return beanProperties;
    }

    /**
     * Method called by {@link BeanSerializerFactory} after collecting all information
     * regarding POJO to serialize and updating builder with it, but before constructing
     * serializer.
     * Implementations may choose to modify state of builder (to affect serializer being
     * built), or even completely replace it (if they want to build different kind of
     * serializer). Typically, however, passed-in builder is returned, possibly with
     * some modifications.
     */
    public BeanSerializerBuilder updateBuilder(SerializationConfig config,
            BeanDescription beanDesc, BeanSerializerBuilder builder) {
        return builder;
    }
    
    /**
     * Method called by {@link BeanSerializerFactory} after constructing default
     * bean serializer instance with properties collected and ordered earlier.
     * Implementations can modify or replace given serializer and return serializer
     * to use. Note that although initial serializer being passed is of type
     * {@link BeanSerializer}, modifiers may return serializers of other types;
     * and this is why implementations must check for type before casting.
     *<p>
     * NOTE: since 2.2, gets called for serializer of those non-POJO types that
     * do not go through any of more specific <code>modifyXxxSerializer</code>
     * methods; mostly for JDK types like {@link java.util.Iterator} and such.
     */
    public JsonSerializer<?> modifySerializer(SerializationConfig config,
            BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /*
    /**********************************************************
    /* Callback methods for other types (since 2.2)
    /**********************************************************
     */

    /**
     * Method called by {@link DeserializerFactory} after it has constructed the
     * standard serializer for given
     * {@link ArrayType}
     * to make it possible to either replace or augment this serializer with
     * additional functionality.
     * 
     * @param config Configuration in use
     * @param valueType Type of the value serializer is used for.
     * @param beanDesc Details of the type in question, to allow checking class annotations
     * @param serializer Default serializer that would be used.
     * 
     * @return Serializer to use; either <code>serializer</code> that was passed
     *   in, or an instance method constructed.
     * 
     * @since 2.2
     */
    public JsonSerializer<?> modifyArraySerializer(SerializationConfig config,
            ArrayType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /**
     * @since 2.2
     */
    public JsonSerializer<?> modifyCollectionSerializer(SerializationConfig config,
            CollectionType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /**
     * @since 2.2
     */
    public JsonSerializer<?> modifyCollectionLikeSerializer(SerializationConfig config,
            CollectionLikeType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }
    
    /**
     * @since 2.2
     */
    public JsonSerializer<?> modifyMapSerializer(SerializationConfig config,
            MapType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /**
     * @since 2.2
     */
    public JsonSerializer<?> modifyMapLikeSerializer(SerializationConfig config,
            MapLikeType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /**
     * @since 2.2
     */
    public JsonSerializer<?> modifyEnumSerializer(SerializationConfig config,
            JavaType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }

    /**
     * Method called by {@link DeserializerFactory} after it has constructed the
     * default key serializer to use for serializing {@link java.util.Map} keys of
     * given type.
     * This makes it possible to either replace or augment default serializer with
     * additional functionality.
     * 
     * @param config Configuration in use
     * @param valueType Type of keys the serializer is used for.
     * @param beanDesc Details of the type in question, to allow checking class annotations
     * @param serializer Default serializer that would be used.
     * 
     * @return Serializer to use; either <code>serializer</code> that was passed
     *   in, or an instance method constructed.
     * 
     * @since 2.2
     */
    public JsonSerializer<?> modifyKeySerializer(SerializationConfig config,
            JavaType valueType, BeanDescription beanDesc, JsonSerializer<?> serializer) {
        return serializer;
    }
}

⏎ com/fasterxml/jackson/databind/ser/BeanSerializerModifier.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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