Is there a J2ME implementation for Java SE\C++?

Question

Java

It became interesting to delve into java me, specifically interested in the following:
1) Where can I read a comprehensive explanation of Java ME? Those. there is some kind of os in which jvm is built in and calls to the periphery are thrown, or there is midp which is essentially a piece \ implementation of java me for mobile phones, etc. .
2) Is there a j2me emulator for java se and/or c++? I’ll explain a little here, I mean something that can be connected to another program, for example, to the same java se and describe only the equipment interfaces (screen, buttons, etc.) and then call / launch the necessary midlets directly from the main program.
3)

All this is interesting purely for the study and knowledge of technology, therefore I am looking for just such an emulator and not a piece of iron to study the device and the principles of writing interfaces / virtual device drivers for jvm j2me.

Answer 1

CLDC and MIDP are just standard Java ME libraries. The first is the native capabilities of the processor and JVM, which are more limited than Java SE. The second is access to the phone's hardware: LCDUI, MMAPI, and so on. Another difference is the so-called. preverification of classes (Java SE calculates information about classes itself, and Java ME with a castrated loader relies on calculation on a desktop computer).
How they are architecturally implemented, what percentage of libraries is written in Java and what percentage is in machine code - a Java ME programmer is not at all interested (except when some class is buggy on a mobile phone). That's why he and ME, which gives a simple framework for writing software for mobile phones.
Some kind of emulator is in the Java ME SDK. How to configure it for the desired mobile phone, I do not know.
There is also MicroEmulator:https://code.google.com/archive/p/microemu/downloads . If you want to be such an elite Java ME that you will write your own drivers (or just embed ME support somewhere in another program), I think MicroEmulator is a good testing ground. The usual ME'shnik does not write drivers, they are written by the authors of mobile phone firmware.

Answer 2

The microemulator repository on github, google code is a little out of trend and not so convenient. I dug into it, this is exactly what you need, a clean implementation of CLDC and MIDP on a regular java se, and it is also ported to everything that is possible.