// Copy-paste all declared fields to new instance

package gof.prototype;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.List;

/**
 *
 * @author Wojciech
 */
public interface IPrototype extends Serializable{

    default public <T> T deepClone() {
        T clone = null;
        try {
            ByteArrayOutputStream baOUT = new ByteArrayOutputStream();
            ObjectOutputStream oOUT = new ObjectOutputStream(baOUT);
            oOUT.writeObject(this);

            ByteArrayInputStream baIN = new ByteArrayInputStream(baOUT.toByteArray());
            ObjectInputStream oIN = new ObjectInputStream(baIN);
            clone = (T) oIN.readObject();
        } catch (IOException | ClassNotFoundException e) {//Java 7 required
            e.printStackTrace();
        }
        return clone;
    }
    default public <T> T shallowClone() {
        T clone = null;
        try {
// Get object's constructor
            Constructor[] constructors = this.getClass().getDeclaredConstructors();

// Check if constructor exists
            if (constructors.length == 0) {
                throw new InstantiationException("No constructor was found.");
            }

// Prepare null/zero constructor param list
            List<Object> paramList = new ArrayList();

// Get constructor param types
            Class[] paramTypes = constructors[0].getParameterTypes();

// Fill in param list
            for (Class paramType : paramTypes) {
                if (paramType.isPrimitive()) {
                    paramList.add(0);
                } else {
                    paramList.add(null);
                }
            }

// Create 'empty' instance
            clone = (T) constructors[0].newInstance(paramList.toArray());

// Copy-paste all declared fields to new instance
            Field[] fields = this.getClass().getDeclaredFields();
            for (Field field : fields) {
                field.set(clone, field.get(this));
            }

        } catch (InstantiationException | IllegalAccessException | IllegalArgumentException | InvocationTargetException ex) {
        }

        return clone;
    }
}