The document discusses implementing Java MIDP on HTML5 and Flash. It describes compiling Java source code into JavaScript and ActionScript using a custom compiler. This allows Java applications to run within a web browser using HTML5 or Flash instead of on a mobile device. An example of compiling a simple Java while loop into JavaScript and x86 machine code is provided to illustrate the compiler approach.

1. Java MIDP implementation
on
HTML5 and Flash
Yu Kobayashi
(yukoba)

2. Who am I?
□ “Virtual Machines on JavaScript and
ActionScript” OTAKU
□ My 4th
project of screen sharing
implemented by JavaScript and
ActionScript

3. Web Browser
HTML5 Flash
Java MIDP Implementation
Application

4. My Compiler
Java class file
JavaScript ActionScript
Java source code

5. Demo

6. http://orto-app.com/
Just release now!
Alpha Version

7. Control Flow Graph

8. Java Source code
a = 1
b = 1
while (true) {
c = a + b;
System.out.println(c);
a = b;
b = c;
}
a = 1
b = 1
Is thread resume?
Resume
System.out.println(c)
c = a + b
System.out.println(c)
a = b
b = c

9. Java mnemonic
iload 2
istore 1
iload 3
istore 2
Java source code
a = b
b = c
JavaScript
stack.push(localVar2)
localVar1 = stack.pop()
stack.push(localVar3)
localVar2 = stack.pop()
More Optimized JavaScript
localVar1 = localVar2
localVar2 = localVar3
JIT x86
mov eax, [0004h]
mov [0000h], eax
mov eax, [0008h]
mov [0004h], eax
Optimized JavaScript
stack1 = localVar2
localVar1 = stack1
stack1 = localVar3
localVar2 = stack1

10. Java mnemonic
iload 2
istore 1
iload 3
istore 2
Java source code
a = b
b = c
JavaScript
stack.push(localVar2)
localVar1 = stack.pop()
stack.push(localVar3)
localVar2 = stack.pop()
More Optimized JavaScript
localVar1 = localVar2
localVar2 = localVar3
JIT x86
mov eax, [0004h]
mov [0000h], eax
mov eax, [0008h]
mov [0004h], eax
Optimized JavaScript
stack1 = localVar2
localVar1 = stack1
stack1 = localVar3
localVar2 = stack1