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-2.12.4-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Databind Source Code below:

⏎ com/fasterxml/jackson/databind/introspect/AnnotatedConstructor.java

package com.fasterxml.jackson.databind.introspect;

import java.lang.reflect.*;

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

public final class AnnotatedConstructor
    extends AnnotatedWithParams
{
    private static final long serialVersionUID = 1L;

    protected final Constructor<?> _constructor;

    /**
     * Field that is used to make JDK serialization work with this
     * object.
     * 
     * @since 2.1
     */
    protected Serialization _serialization;

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

    public AnnotatedConstructor(TypeResolutionContext ctxt, Constructor<?> constructor,
            AnnotationMap classAnn, AnnotationMap[] paramAnn)
    {
        super(ctxt, classAnn, paramAnn);
        if (constructor == null) {
            throw new IllegalArgumentException("Null constructor not allowed");
        }
        _constructor = constructor;
    }

    /**
     * Method used for JDK serialization support
     * @since 2.1
     */
    protected AnnotatedConstructor(Serialization ser)
    {
        super(null, null, null);
        _constructor = null;
        _serialization = ser;
    }
    
    @Override
    public AnnotatedConstructor withAnnotations(AnnotationMap ann) {
        return new AnnotatedConstructor(_typeContext, _constructor, ann, _paramAnnotations);
    }
    
    /*
    /**********************************************************
    /* Annotated impl
    /**********************************************************
     */

    @Override
    public Constructor<?> getAnnotated() { return _constructor; }

    @Override
    public int getModifiers() { return _constructor.getModifiers(); }

    @Override
    public String getName() { return _constructor.getName(); }

    @Override
    public JavaType getType() {
        return _typeContext.resolveType(getRawType());
    }

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

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

    @Override
    public int getParameterCount() {
        return _constructor.getParameterTypes().length;
    }

    @Override
    public Class<?> getRawParameterType(int index)
    {
        Class<?>[] types = _constructor.getParameterTypes();
        return (index >= types.length) ? null : types[index];
    }

    @Override
    public JavaType getParameterType(int index) {
        Type[] types = _constructor.getGenericParameterTypes();
        if (index >= types.length) {
            return null;
        }
        return _typeContext.resolveType(types[index]);
    }

    @Override
    @Deprecated // since 2.7
    public Type getGenericParameterType(int index) {
        Type[] types = _constructor.getGenericParameterTypes();
        if (index >= types.length) {
            return null;
        }
        return types[index];
    }
    
    @Override
    public final Object call() throws Exception {
        return _constructor.newInstance();
    }

    @Override
    public final Object call(Object[] args) throws Exception {
        return _constructor.newInstance(args);
    }

    @Override
    public final Object call1(Object arg) throws Exception {
        return _constructor.newInstance(arg);
    }
    
    /*
    /**********************************************************
    /* AnnotatedMember impl
    /**********************************************************
     */

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

    @Override
    public Member getMember() { return _constructor; }

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

    @Override
    public Object getValue(Object pojo)
        throws UnsupportedOperationException
    {
        throw new UnsupportedOperationException("Cannot call getValue() on constructor of "
                +getDeclaringClass().getName());
    }
    
    /*
    /**********************************************************
    /* Extended API, specific annotations
    /**********************************************************
     */

    @Override
    public String toString() {
        // 03-Nov-2020 ckozak: This can use _constructor.getParameterCount() once java 8 is required.
        final int argCount = _constructor.getParameterTypes().length;
        return String.format("[constructor for %s (%d arg%s), annotations: %s",
                ClassUtil.nameOf(_constructor.getDeclaringClass()), argCount,
                (argCount == 1) ? "" : "s", _annotations);
    }

    @Override
    public int hashCode() {
        return _constructor.getName().hashCode();
    }
    
    @Override
    public boolean equals(Object o) {
        if (o == this) return true;
        return ClassUtil.hasClass(o, getClass())
                && (((AnnotatedConstructor) o)._constructor == _constructor);
    }

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

    Object writeReplace() {
        return new AnnotatedConstructor(new Serialization(_constructor));
    }

    Object readResolve() {
        Class<?> clazz = _serialization.clazz;
        try {
            Constructor<?> ctor = clazz.getDeclaredConstructor(_serialization.args);
            // 06-Oct-2012, tatu: Has "lost" its security override, must force back
            if (!ctor.isAccessible()) {
                ClassUtil.checkAndFixAccess(ctor, false);
            }
            return new AnnotatedConstructor(null, ctor, null, null);
        } catch (Exception e) {
            throw new IllegalArgumentException("Could not find constructor with "
                    +_serialization.args.length+" args from Class '"+clazz.getName());
        }
    }
    
    /**
     * Helper class that is used as the workaround to persist
     * Field references. It basically just stores declaring class
     * and field name.
     */
    private final static class Serialization
        implements java.io.Serializable
    {
        private static final long serialVersionUID = 1L;
        protected Class<?> clazz;
        protected Class<?>[] args;

        public Serialization(Constructor<?> ctor) {
            clazz = ctor.getDeclaringClass();
            args = ctor.getParameterTypes();
        }
    }
}

⏎ com/fasterxml/jackson/databind/introspect/AnnotatedConstructor.java

 

⇒ Jackson Annotations Source Code

⇐ Download and Install Jackson Binary Package

⇑ Downloading and Reviewing jackson-*.jar

⇑⇑ Jackson - Java JSON library