Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Annotations Source Code files are provided in the source packge (jackson-annotations-2.12.4-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Annotations Source Code below:

⏎ com/fasterxml/jackson/databind/deser/impl/ObjectIdReader.java

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

import java.io.IOException;

import com.fasterxml.jackson.annotation.ObjectIdGenerator;
import com.fasterxml.jackson.annotation.ObjectIdResolver;

import com.fasterxml.jackson.core.JsonParser;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.SettableBeanProperty;

/**
 * Object that knows how to deserialize Object Ids.
 */
public class ObjectIdReader
    implements java.io.Serializable
{
    private static final long serialVersionUID = 1L;

    protected final JavaType _idType;

    public final PropertyName propertyName;
    
    /**
     * Blueprint generator instance: actual instance will be
     * fetched from {@link SerializerProvider} using this as
     * the key.
     */
    public final ObjectIdGenerator<?> generator;

    public final ObjectIdResolver resolver;

    /**
     * Deserializer used for deserializing id values.
     */
    protected final JsonDeserializer<Object> _deserializer;

    public final SettableBeanProperty idProperty;
    
    /*
    /**********************************************************
    /* Life-cycle
    /**********************************************************
     */
    
    @SuppressWarnings("unchecked")
    protected ObjectIdReader(JavaType t, PropertyName propName, ObjectIdGenerator<?> gen,
            JsonDeserializer<?> deser, SettableBeanProperty idProp, ObjectIdResolver resolver)
    {
        _idType = t;
        propertyName = propName;
        generator = gen;
        this.resolver = resolver;
        _deserializer = (JsonDeserializer<Object>) deser;
        idProperty = idProp;
    }

    /**
     * Factory method called by {@link com.fasterxml.jackson.databind.ser.std.BeanSerializerBase}
     * with the initial information based on standard settings for the type
     * for which serializer is being built.
     */
    public static ObjectIdReader construct(JavaType idType, PropertyName propName,
            ObjectIdGenerator<?> generator, JsonDeserializer<?> deser,
            SettableBeanProperty idProp, ObjectIdResolver resolver)
    {
        return new ObjectIdReader(idType, propName, generator, deser, idProp, resolver);
    }

    /*
    /**********************************************************
    /* API
    /**********************************************************
     */

    public JsonDeserializer<Object> getDeserializer() {
        return _deserializer;
    }

    public JavaType getIdType() {
        return _idType;
    }

    /**
     * Convenience method, equivalent to calling:
     *<code>
     *  readerInstance.generator.maySerializeAsObject();
     *</code>
     * and used to determine whether Object Ids handled by the underlying
     * generator may be in form of (JSON) Objects.
     * Used for optimizing handling in cases where method returns false.
     * 
     * @since 2.5
     */
    public boolean maySerializeAsObject() {
        return generator.maySerializeAsObject();
    }

    /**
     * Convenience method, equivalent to calling:
     *<code>
     *  readerInstance.generator.isValidReferencePropertyName(name, parser);
     *</code>
     * and used to determine whether Object Ids handled by the underlying
     * generator may be in form of (JSON) Objects.
     * Used for optimizing handling in cases where method returns false.
     * 
     * @since 2.5
     */
    public boolean isValidReferencePropertyName(String name, JsonParser parser) {
        return generator.isValidReferencePropertyName(name, parser);
    }
    
    /**
     * Method called to read value that is expected to be an Object Reference
     * (that is, value of an Object Id used to refer to another object).
     * 
     * @since 2.3
     */
    public Object readObjectReference(JsonParser jp, DeserializationContext ctxt) throws IOException {
        return _deserializer.deserialize(jp, ctxt);
    }
}

⏎ com/fasterxml/jackson/databind/deser/impl/ObjectIdReader.java

 

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