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/ser/impl/ObjectIdWriter.java

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

import com.fasterxml.jackson.annotation.ObjectIdGenerator;
import com.fasterxml.jackson.core.SerializableString;
import com.fasterxml.jackson.core.io.SerializedString;
import com.fasterxml.jackson.databind.*;

/**
 * Object that knows how to serialize Object Ids.
 */
public final class ObjectIdWriter
{
    public final JavaType idType;

    /**
     * Name of id property to write, if not null: if null, should
     * only write references, but id property is handled by some
     * other entity.
     */
    public final SerializableString propertyName;

    /**
     * Blueprint generator instance: actual instance will be
     * fetched from {@link SerializerProvider} using this as
     * the key.
     */
    public final ObjectIdGenerator<?> generator;
    
    /**
     * Serializer used for serializing id values.
     */
    public final JsonSerializer<Object> serializer;

    /**
     * Marker that indicates what the first reference is to be
     * serialized as full POJO, or as Object Id (other references
     * will always be serialized as Object Id)
     * 
     * @since 2.1
     */
    public final boolean alwaysAsId;
    
    /*
    /**********************************************************
    /* Life-cycle
    /**********************************************************
     */

    @SuppressWarnings("unchecked")
    protected ObjectIdWriter(JavaType t, SerializableString propName,
            ObjectIdGenerator<?> gen, JsonSerializer<?> ser, boolean alwaysAsId)
    {
        idType = t;
        propertyName = propName;
        generator = gen;
        serializer = (JsonSerializer<Object>) ser;
        this.alwaysAsId = alwaysAsId;
    }

    /**
     * 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.
     * 
     * @since 2.3
     */
    public static ObjectIdWriter construct(JavaType idType, PropertyName propName,
            ObjectIdGenerator<?> generator, boolean alwaysAsId)
    {
        String simpleName = (propName == null) ? null : propName.getSimpleName();
        SerializableString serName = (simpleName == null) ? null : new SerializedString(simpleName);
        return new ObjectIdWriter(idType, serName, generator, null, alwaysAsId);
    }

    public ObjectIdWriter withSerializer(JsonSerializer<?> ser) {
        return new ObjectIdWriter(idType, propertyName, generator, ser, alwaysAsId);
    }

    /**
     * @since 2.1
     */
    public ObjectIdWriter withAlwaysAsId(boolean newState) {
        if (newState == alwaysAsId) {
            return this;
        }
        return new ObjectIdWriter(idType, propertyName, generator, serializer, newState);
    }
}

⏎ com/fasterxml/jackson/databind/ser/impl/ObjectIdWriter.java

 

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