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/deser/impl/NullsFailProvider.java

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

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.NullValueProvider;
import com.fasterxml.jackson.databind.exc.InvalidNullException;
import com.fasterxml.jackson.databind.util.AccessPattern;

/**
 * Simple {@link NullValueProvider} that will always throw a
 * {@link InvalidNullException} when a null is encountered.
 */
public class NullsFailProvider
    implements NullValueProvider, java.io.Serializable
{
    private static final long serialVersionUID = 1L;

    protected final PropertyName _name;
    protected final JavaType _type;

    protected NullsFailProvider(PropertyName name, JavaType type) {
        _name = name;
        _type = type;
    }

    public static NullsFailProvider constructForProperty(BeanProperty prop) {
        return constructForProperty(prop, prop.getType());
    }

    // @since 2.10.2
    public static NullsFailProvider constructForProperty(BeanProperty prop, JavaType type) {
        return new NullsFailProvider(prop.getFullName(), type);
    }

    public static NullsFailProvider constructForRootValue(JavaType t) {
        return new NullsFailProvider(null, t);
    }

    @Override
    public AccessPattern getNullAccessPattern() {
        // Must be called every time to effect the exception...
        return AccessPattern.DYNAMIC;
    }

    @Override
    public Object getNullValue(DeserializationContext ctxt)
            throws JsonMappingException {
        throw InvalidNullException.from(ctxt, _name, _type);
    }
}

⏎ com/fasterxml/jackson/databind/deser/impl/NullsFailProvider.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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⇑⇑ Jackson - Java JSON library