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/annotation/JsonDeserialize.java

package com.fasterxml.jackson.databind.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.KeyDeserializer;
import com.fasterxml.jackson.databind.util.Converter;

/**
 * Annotation use for configuring deserialization aspects, by attaching
 * to "setter" methods or fields, or to value classes.
 * When annotating value classes, configuration is used for instances
 * of the value class but can be overridden by more specific annotations
 * (ones that attach to methods or fields).
 *<p>
 * An example annotation would be:
 *<pre>
 *  &#64;JsonDeserialize(using=MySerializer.class,
 *    as=MyHashMap.class,
 *    keyAs=MyHashKey.class,
 *    contentAs=MyHashValue.class
 *  )
 *</pre>
 *<p>
 * Something to note on usage:
 *<ul>
 * <li>All other annotations regarding behavior during building should be on <b>Builder</b>
 *    class and NOT on target POJO class: for example &#64;JsonIgnoreProperties should be on
 *    Builder to prevent "unknown property" errors.
 *  </li>
 * <li>Similarly configuration overrides (see {@link com.fasterxml.jackson.databind.ObjectMapper#configOverride})
 *    should be targeted at Builder class, not target POJO class.
 *  </li>
 * </ul>
 *
 */
@Target({ElementType.ANNOTATION_TYPE, ElementType.METHOD, ElementType.FIELD, ElementType.TYPE, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@com.fasterxml.jackson.annotation.JacksonAnnotation
public @interface JsonDeserialize
{
    // // // Annotations for explicitly specifying deserialize/builder

    /**
     * Deserializer class to use for deserializing associated value.
     * Depending on what is annotated,
     * value is either an instance of annotated class (used globablly
     * anywhere where class deserializer is needed); or only used for
     * deserializing the value of the property annotated.
     */
    @SuppressWarnings("rawtypes") // to work around JDK8 bug wrt Class-valued annotation properties
    public Class<? extends JsonDeserializer> using()
        default JsonDeserializer.None.class;

    /**
     * Deserializer class to use for deserializing contents (elements
     * of a Collection/array, values of Maps) of annotated property.
     * Can only be used on accessors (methods, fields, constructors), to
     * apply to values of {@link java.util.Map}-valued properties; not
     * applicable for value types used as Array elements
     * or {@link java.util.Collection} and {@link java.util.Map} values.
     */
    @SuppressWarnings("rawtypes") // to work around JDK8 bug wrt Class-valued annotation properties
    public Class<? extends JsonDeserializer> contentUsing()
        default JsonDeserializer.None.class;

    /**
     * Deserializer class to use for deserializing Map keys
     * of annotated property or Map keys of value type so annotated.
     * Can be used both on accessors (methods, fields, constructors), to
     * apply to values of {@link java.util.Map}-valued properties, and
     * on "key" classes, to apply to use of annotated type as
     * {@link java.util.Map} keys (latter starting with Jackson 2.11).
     */
    public Class<? extends KeyDeserializer> keyUsing()
        default KeyDeserializer.None.class;

    /**
     * Annotation for specifying if an external Builder class is to
     * be used for building up deserialized instances of annotated
     * class. If so, an instance of referenced class is first constructed
     * (possibly using a Creator method; or if none defined, using default
     * constructor), and its "with-methods" are used for populating fields;
     * and finally "build-method" is invoked to complete deserialization.
     */
    public Class<?> builder() default Void.class;

    // // // Annotations for specifying intermediate Converters (2.2+)
    
    /**
     * Which helper object (if any) is to be used to convert from Jackson-bound
     * intermediate type (source type of converter) into actual property type
     * (which must be same as result type of converter). This is often used
     * for two-step deserialization; Jackson binds data into suitable intermediate
     * type (like Tree representation), and converter then builds actual property
     * type.
     *
     * @since 2.2
     */
    @SuppressWarnings("rawtypes") // to work around JDK8 bug wrt Class-valued annotation properties
    public Class<? extends Converter> converter() default Converter.None.class;

    /**
     * Similar to {@link #converter}, but used for values of structures types
     * (List, arrays, Maps).
     *
     * @since 2.2
     */
    @SuppressWarnings("rawtypes") // to work around JDK8 bug wrt Class-valued annotation properties
    public Class<? extends Converter> contentConverter() default Converter.None.class;
    
    
    // // // Annotations for explicitly specifying deserialization type
    // // // (which is used for choosing deserializer, if not explicitly
    // // // specified

    /**
     * Concrete type to deserialize values as, instead of type otherwise
     * declared. Must be a subtype of declared type; otherwise an
     * exception may be thrown by deserializer.
     *<p>
     * Bogus type {@link Void} can be used to indicate that declared
     * type is used as is (i.e. this annotation property has no setting);
     * this since annotation properties are not allowed to have null value.
     *<p>
     * Note: if {@link #using} is also used it has precedence
     * (since it directly specified
     * deserializer, whereas this would only be used to locate the
     * deserializer)
     * and value of this annotation property is ignored.
     */
    public Class<?> as() default Void.class;

    /**
     * Concrete type to deserialize keys of {@link java.util.Map} as,
     * instead of type otherwise declared.
     * Must be a subtype of declared type; otherwise an exception may be
     * thrown by deserializer.
     */
    public Class<?> keyAs() default Void.class;

    /**
     * Concrete type to deserialize content (elements
     * of a Collection/array, values of Maps) values as,
     * instead of type otherwise declared.
     * Must be a subtype of declared type; otherwise an exception may be
     * thrown by deserializer.
     */
    public Class<?> contentAs() default Void.class;
}

⏎ com/fasterxml/jackson/databind/annotation/JsonDeserialize.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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