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/introspect/AnnotatedParameter.java

package com.fasterxml.jackson.databind.introspect;

import java.lang.reflect.*;

import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.util.ClassUtil;

/**
 * Object that represents method parameters, mostly so that associated
 * annotations can be processed conveniently. Note that many of accessors
 * cannot return meaningful values since parameters do not have stand-alone
 * JDK objects associated; so access should mostly be limited to checking
 * annotation values which are properly aggregated and included.
 */
public final class AnnotatedParameter
    extends AnnotatedMember
{
    private static final long serialVersionUID = 1L;

    /**
     * Member (method, constructor) that this parameter belongs to
     */
    protected final AnnotatedWithParams _owner;
    
    /**
     * JDK type of the parameter, possibly contains generic type information
     */
    protected final JavaType _type;
    
    /**
     * Index of the parameter within argument list
     */
    protected final int _index;

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

    public AnnotatedParameter(AnnotatedWithParams owner, JavaType type,
            TypeResolutionContext typeContext,
            AnnotationMap annotations, int index)
    {
        super(typeContext, annotations);
        _owner = owner;
        _type = type;
        _index = index;
    }

    @Override
    public AnnotatedParameter withAnnotations(AnnotationMap ann) {
        if (ann == _annotations) {
            return this;
        }
        return _owner.replaceParameterAnnotations(_index, ann);
    }

    /*
    /**********************************************************
    /* Annotated impl
    /**********************************************************
     */

    /**
     * Since there is no matching JDK element, this method will
     * always return null
     */
    @Override
    public AnnotatedElement getAnnotated() { return null; }

    /**
     * Returns modifiers of the constructor, as parameters do not
     * have independent modifiers.
     */
    @Override
    public int getModifiers() { return _owner.getModifiers(); }

    /**
     * Parameters have no names in bytecode (unlike in source code),
     * will always return empty String ("").
     */
    @Override
    public String getName() { return ""; }

    @Override
    public Class<?> getRawType() {
        return _type.getRawClass();
    }

    @Override
    public JavaType getType() {
        return _type;
    }

    /*
    /**********************************************************
    /* AnnotatedMember extras
    /**********************************************************
     */

    @Override
    public Class<?> getDeclaringClass() {
        return _owner.getDeclaringClass();
    }

    @Override
    public Member getMember() {
        // This is bit tricky: since there is no JDK equivalent; can either
        // return null or owner... let's do latter, for now.
        return _owner.getMember();
    }

    @Override
    public void setValue(Object pojo, Object value) throws UnsupportedOperationException
    {
        throw new UnsupportedOperationException("Cannot call setValue() on constructor parameter of "
                +getDeclaringClass().getName());
    }

    @Override
    public Object getValue(Object pojo) throws UnsupportedOperationException
    {
        throw new UnsupportedOperationException("Cannot call getValue() on constructor parameter of "
                +getDeclaringClass().getName());
    }

    /*
    /**********************************************************
    /* Extended API
    /**********************************************************
     */

    public Type getParameterType() { return _type; }

    /**
     * Accessor for 'owner' of this parameter; method or constructor that
     * has this parameter as member of its argument list.
     * 
     * @return Owner (member or creator) object of this parameter
     */
    public AnnotatedWithParams getOwner() { return _owner; }
    
    /**
     * Accessor for index of this parameter within argument list
     * 
     * @return Index of this parameter within argument list
     */
    public int getIndex() { return _index; }

    /*
    /********************************************************
    /* Other
    /********************************************************
     */
    
    @Override
    public int hashCode() {
        return _owner.hashCode() + _index;
    }
    
    @Override
    public boolean equals(Object o) {
        if (o == this) return true;
        if (!ClassUtil.hasClass(o, getClass())) {
            return false;
        }
        AnnotatedParameter other = (AnnotatedParameter) o;
        return other._owner.equals(_owner) && (other._index == _index);
    }
    
    @Override
    public String toString() {
        return "[parameter #"+getIndex()+", annotations: "+_annotations+"]";
    }
}

⏎ com/fasterxml/jackson/databind/introspect/AnnotatedParameter.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 

⇒ Jackson Annotations Source Code

⇐ Download and Install Jackson Binary Package

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