/**

* Copyright (c) 2024 Araf Karsh Hamid

* <p>

* Permission is hereby granted, free of charge, to any person obtaining a copy

* of this software and associated documentation files (the "Software"), to deal

* in the Software without restriction, including without limitation the rights

* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

* copies of the Software, and to permit persons to whom the Software is

* furnished to do so, subject to the following conditions:

* <p>

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

* THE SOFTWARE.

* <p>

* This program and the accompanying materials are dual-licensed under

* either the terms of the Eclipse Public License v1.0 as published by

* the Eclipse Foundation

* <p>

* or (per the licensee's choosing)

* <p>

* under the terms of the Apache 2 License version 2.0

* as published by the Apache Software Foundation.

*/

package java18;

import java.lang.invoke.MethodHandle;

import java.lang.invoke.MethodHandles;

import java.lang.invoke.MethodType;

import java.lang.reflect.Method;

import static java.lang.System.out;

/**

* JavaExamples / ReflectionExample

*

* JEP 416: Reimplement Core Reflection with Method Handles

*

* Java 18 reimplements parts of the core reflection using MethodHandles to improve performance

* and reduce the maintenance burden.

*

* @author: Araf Karsh Hamid

* @version: 0.1

* @date: 2024-09-29T21:29

*/

public class ReflectionExample {

public static void main(String[] args) throws Throwable {

// Java 18

out.println("JAVA 18 >>>>>--------------------------------------------------------");

oldModel();

newModel();

}

/**

* Old API Model

* @throws Throwable

*/

public static void oldModel() throws Throwable {

out.println("Old Reflection Model... ");

// Obtain the Class object for String

Class<String> stringClass = String.class;

// Get the method reference to `toUpperCase` with no parameters

Method toUpperCaseMethod = stringClass.getMethod("toUpperCase");

// Invoke the method on an instance of String

String result = (String) toUpperCaseMethod.invoke("hello");

System.out.println(result); // Outputs: HELLO

}

/**

* New Much Simpler high performance API

* @throws Throwable

*/

public static void newModel() throws Throwable {

out.println("New Reflection Model... ");

MethodHandles.Lookup lookup = MethodHandles.lookup();

MethodHandle handle = lookup.findVirtual(String.class, "toUpperCase", MethodType.methodType(String.class));

String result = (String) handle.invoke("hello");

System.out.println(result);

}

}