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/SettableAnyProperty.java

package com.fasterxml.jackson.databind.deser;

import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.impl.JDKValueInstantiators;
import com.fasterxml.jackson.databind.deser.impl.ReadableObjectId.Referring;
import com.fasterxml.jackson.databind.introspect.AnnotatedField;
import com.fasterxml.jackson.databind.introspect.AnnotatedMember;
import com.fasterxml.jackson.databind.introspect.AnnotatedMethod;
import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.fasterxml.jackson.databind.util.ClassUtil;

/**
 * Class that represents a "wildcard" set method which can be used
 * to generically set values of otherwise unmapped (aka "unknown")
 * properties read from JSON content.
 *<p>
 * Note: starting with 2.14, is {@code abstract} class with multiple
 * concrete implementations
 */
public abstract class SettableAnyProperty
    implements java.io.Serializable
{
    private static final long serialVersionUID = 1L;
    
    /**
     * Method used for setting "any" properties, along with annotation
     * information. Retained to allow contextualization of any properties.
     */
    protected final BeanProperty _property;

    /**
     * Annotated variant is needed for JDK serialization only
     */
    protected final AnnotatedMember _setter;

    protected final boolean _setterIsField;

    protected final JavaType _type;

    protected JsonDeserializer<Object> _valueDeserializer;

    protected final TypeDeserializer _valueTypeDeserializer;

    /**
     * @since 2.9
     */
    protected final KeyDeserializer _keyDeserializer;

    /*
    /**********************************************************
    /* Life-cycle
    /**********************************************************
     */

    public SettableAnyProperty(BeanProperty property, AnnotatedMember setter, JavaType type,
            KeyDeserializer keyDeser,
            JsonDeserializer<Object> valueDeser, TypeDeserializer typeDeser)
    {
        _property = property;
        _setter = setter;
        _type = type;
        _valueDeserializer = valueDeser;
        _valueTypeDeserializer = typeDeser;
        _keyDeserializer = keyDeser;
        _setterIsField = setter instanceof AnnotatedField;
    }

    /**
     * @since 2.14
     */
    public static SettableAnyProperty constructForMethod(DeserializationContext ctxt,
            BeanProperty property,
            AnnotatedMember field, JavaType valueType,
            KeyDeserializer keyDeser,
            JsonDeserializer<Object> valueDeser, TypeDeserializer typeDeser) {
        return new MethodAnyProperty(property, field, valueType,
                keyDeser, valueDeser, typeDeser);
    }

    /**
     * @since 2.14
     */
    public static SettableAnyProperty constructForMapField(DeserializationContext ctxt,
            BeanProperty property,
            AnnotatedMember field, JavaType valueType,
            KeyDeserializer keyDeser,
            JsonDeserializer<Object> valueDeser, TypeDeserializer typeDeser)
    {
        Class<?> mapType = field.getRawType();
        // 02-Aug-2022, tatu: Ideally would be resolved to a concrete type by caller but
        //    alas doesn't appear to happen. Nor does `BasicDeserializerFactory` expose method
        //    for finding default or explicit mappings.
        if (mapType == Map.class) {
            mapType = LinkedHashMap.class;
        }
        ValueInstantiator vi = JDKValueInstantiators.findStdValueInstantiator(ctxt.getConfig(), mapType);
        return new MapFieldAnyProperty(property, field, valueType,
                keyDeser, valueDeser, typeDeser,
                vi);
    }

    /**
     * @since 2.14
     */
    public static SettableAnyProperty constructForJsonNodeField(DeserializationContext ctxt,
            BeanProperty property,
            AnnotatedMember field, JavaType valueType, JsonDeserializer<Object> valueDeser) {
        return new JsonNodeFieldAnyProperty(property, field, valueType,
                valueDeser,
                ctxt.getNodeFactory());
    }

    // Abstract @since 2.14
    public abstract SettableAnyProperty withValueDeserializer(JsonDeserializer<Object> deser);

    public void fixAccess(DeserializationConfig config) {
        _setter.fixAccess(
                config.isEnabled(MapperFeature.OVERRIDE_PUBLIC_ACCESS_MODIFIERS));
    }

    /*
    /**********************************************************
    /* JDK serialization handling
    /**********************************************************
     */

    /**
     * Need to define this to verify that we retain actual Method reference
     */
    Object readResolve() {
        // sanity check...
        if (_setter == null || _setter.getAnnotated() == null) {
            throw new IllegalArgumentException("Missing method/field (broken JDK (de)serialization?)");
        }
        return this;
    }
    
    /*
    /**********************************************************
    /* Public API, accessors
    /**********************************************************
     */

    public BeanProperty getProperty() { return _property; }
    
    public boolean hasValueDeserializer() { return (_valueDeserializer != null); }

    public JavaType getType() { return _type; }

    /**
     * @since 2.14
     */
    public String getPropertyName() { return _property.getName(); }

    /*
    /**********************************************************
    /* Public API, deserialization
    /**********************************************************
     */
    
    /**
     * Method called to deserialize appropriate value, given parser (and
     * context), and set it using appropriate method (a setter method).
     */
    public void deserializeAndSet(JsonParser p, DeserializationContext ctxt,
            Object instance, String propName)
        throws IOException
    {
        try {
            Object key = (_keyDeserializer == null) ? propName
                    : _keyDeserializer.deserializeKey(propName, ctxt);
            set(instance, key, deserialize(p, ctxt));
        } catch (UnresolvedForwardReference reference) {
            if (!(_valueDeserializer.getObjectIdReader() != null)) {
                throw JsonMappingException.from(p, "Unresolved forward reference but no identity info.", reference);
            }
            AnySetterReferring referring = new AnySetterReferring(this, reference,
                    _type.getRawClass(), instance, propName);
            reference.getRoid().appendReferring(referring);
        }
    }

    public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOException
    {
        if (p.hasToken(JsonToken.VALUE_NULL)) {
            return _valueDeserializer.getNullValue(ctxt);
        }
        if (_valueTypeDeserializer != null) {
            return _valueDeserializer.deserializeWithType(p, ctxt, _valueTypeDeserializer);
        }
        return _valueDeserializer.deserialize(p, ctxt);
    }

    // Default implementation since 2.14
    public void set(Object instance, Object propName, Object value) throws IOException
    {
        try {
            _set(instance, propName, value);
        } catch (IOException e) {
            throw e;
        } catch (Exception e) {
            _throwAsIOE(e, propName, value);
        }
    }

    protected abstract void _set(Object instance, Object propName, Object value) throws Exception;

    /*
    /**********************************************************
    /* Helper methods
    /**********************************************************
     */

    /**
     * @param e Exception to re-throw or wrap
     * @param propName Name of property (from Json input) to set
     * @param value Value of the property
     */
    protected void _throwAsIOE(Exception e, Object propName, Object value)
        throws IOException
    {
        if (e instanceof IllegalArgumentException) {
            String actType = ClassUtil.classNameOf(value);
            StringBuilder msg = new StringBuilder("Problem deserializing \"any-property\" '").append(propName);
            msg.append("' of class "+getClassName()+" (expected type: ").append(_type);
            msg.append("; actual type: ").append(actType).append(")");
            String origMsg = ClassUtil.exceptionMessage(e);
            if (origMsg != null) {
                msg.append(", problem: ").append(origMsg);
            } else {
                msg.append(" (no error message provided)");
            }
            throw new JsonMappingException(null, msg.toString(), e);
        }
        ClassUtil.throwIfIOE(e);
        ClassUtil.throwIfRTE(e);
        // let's wrap the innermost problem
        Throwable t = ClassUtil.getRootCause(e);
        throw new JsonMappingException(null, ClassUtil.exceptionMessage(t), t);
    }

    private String getClassName() { return ClassUtil.nameOf(_setter.getDeclaringClass()); }

    @Override public String toString() { return "[any property on class "+getClassName()+"]"; }

    private static class AnySetterReferring extends Referring {
        private final SettableAnyProperty _parent;
        private final Object _pojo;
        private final String _propName;

        public AnySetterReferring(SettableAnyProperty parent,
                UnresolvedForwardReference reference, Class<?> type, Object instance, String propName)
        {
            super(reference, type);
            _parent = parent;
            _pojo = instance;
            _propName = propName;
        }

        @Override
        public void handleResolvedForwardReference(Object id, Object value)
            throws IOException
        {
            if (!hasId(id)) {
                throw new IllegalArgumentException("Trying to resolve a forward reference with id [" + id.toString()
                        + "] that wasn't previously registered.");
            }
            _parent.set(_pojo, _propName, value);
        }
    }

    /*
    /**********************************************************************
    /* Concrete implementations
    /**********************************************************************
     */

    /**
     * @since 2.14
     */
    protected static class MethodAnyProperty extends SettableAnyProperty
        implements java.io.Serializable
    {
        private static final long serialVersionUID = 1L;

        public MethodAnyProperty(BeanProperty property,
                AnnotatedMember field, JavaType valueType,
                KeyDeserializer keyDeser,
                JsonDeserializer<Object> valueDeser, TypeDeserializer typeDeser) {
            super(property, field, valueType,
                    keyDeser, valueDeser, typeDeser);
        }

        @Override
        protected void _set(Object instance, Object propName, Object value) throws Exception
        {
            // note: cannot use 'setValue()' due to taking 2 args
            ((AnnotatedMethod) _setter).callOnWith(instance, propName, value);
        }

        @Override
        public SettableAnyProperty withValueDeserializer(JsonDeserializer<Object> deser) {
            return new MethodAnyProperty(_property, _setter, _type,
                    _keyDeserializer, deser, _valueTypeDeserializer);
        }
    }

    /**
     * @since 2.14
     */
    protected static class MapFieldAnyProperty extends SettableAnyProperty
        implements java.io.Serializable
    {
        private static final long serialVersionUID = 1L;

        protected final ValueInstantiator _valueInstantiator;

        public MapFieldAnyProperty(BeanProperty property,
                AnnotatedMember field, JavaType valueType,
                KeyDeserializer keyDeser,
                JsonDeserializer<Object> valueDeser, TypeDeserializer typeDeser,
                ValueInstantiator inst) {
            super(property, field, valueType,
                    keyDeser, valueDeser, typeDeser);
            _valueInstantiator = inst;
        }

        @Override
        public SettableAnyProperty withValueDeserializer(JsonDeserializer<Object> deser) {
            return new MapFieldAnyProperty(_property, _setter, _type,
                    _keyDeserializer, deser, _valueTypeDeserializer,
                    _valueInstantiator);
        }
        
        @SuppressWarnings("unchecked")
        @Override
        protected void _set(Object instance, Object propName, Object value) throws Exception
        {
            AnnotatedField field = (AnnotatedField) _setter;
            Map<Object,Object> val = (Map<Object,Object>) field.getValue(instance);
            // 01-Aug-2022, tatu: [databind#3559] Will try to create and assign an
            //    instance.
            if (val == null) {
                val = _createAndSetMap(null, field, instance, propName);
            }
            // add the property key and value
            val.put(propName, value);
        }

        @SuppressWarnings("unchecked")
        protected Map<Object, Object> _createAndSetMap(DeserializationContext ctxt, AnnotatedField field,
                Object instance, Object propName)
            throws IOException
        {
            if (_valueInstantiator == null) {
                throw JsonMappingException.from(ctxt, String.format(
                        "Cannot create an instance of %s for use as \"any-setter\" '%s'",
                        ClassUtil.nameOf(_type.getRawClass()), _property.getName()));
            }
            Map<Object,Object> map = (Map<Object,Object>) _valueInstantiator.createUsingDefault(ctxt);
            field.setValue(instance, map);
            return map;
        }
    }

    /**
     * @since 2.14
     */
    protected static class JsonNodeFieldAnyProperty extends SettableAnyProperty
        implements java.io.Serializable
    {
        private static final long serialVersionUID = 1L;

        protected final JsonNodeFactory _nodeFactory;

        public JsonNodeFieldAnyProperty(BeanProperty property,
                AnnotatedMember field, JavaType valueType,
                JsonDeserializer<Object> valueDeser,
                JsonNodeFactory nodeFactory) {
            super(property, field, valueType, null, valueDeser, null);
            _nodeFactory = nodeFactory;
        }

        // Let's override since this is much simpler with JsonNodes
        @Override
        public void deserializeAndSet(JsonParser p, DeserializationContext ctxt,
                Object instance, String propName)
            throws IOException
        {
            setProperty(instance, propName, (JsonNode) deserialize(p, ctxt));
        }

        // Let's override since this is much simpler with JsonNodes
        @Override
        public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOException
        {
            return _valueDeserializer.deserialize(p, ctxt);
        }

        @Override
        protected void _set(Object instance, Object propName, Object value) throws Exception {
            setProperty(instance, (String) propName, (JsonNode) value);
        }

        protected void setProperty(Object instance, String propName, JsonNode value)
            throws IOException
        {
            AnnotatedField field = (AnnotatedField) _setter;
            Object val0 = field.getValue(instance);
            ObjectNode objectNode;

            if (val0 == null) {
                objectNode = _nodeFactory.objectNode();
                field.setValue(instance, objectNode);
            } else if (!(val0 instanceof ObjectNode)) {
                throw JsonMappingException.from((DeserializationContext) null, String.format(
                        "Value \"any-setter\" '%s' not `ObjectNode` but %s",
                        getPropertyName(),
                        ClassUtil.nameOf(val0.getClass())));
            } else {
                objectNode = (ObjectNode) val0;
            }
            // add the property key and value
            objectNode.set(propName, value);
        }

        // Should not get called but...
        @Override
        public SettableAnyProperty withValueDeserializer(JsonDeserializer<Object> deser) {
            return this;
        }
    }
}

⏎ com/fasterxml/jackson/databind/deser/SettableAnyProperty.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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