Dpdl (Dynamic Packet Definition Language)

Dpdl is a rapid development programming language and constrained device framework with built-in database technology.

Dpdl enables access to the Java platform JRE API and to external java libraries and supports the embedding and on-the-fly execution of other programming languages like ANSI C, C++, Python, Julia, JavaScript, Lua, Ruby, Java and Clojure directly within Dpdl code.

Further programming languages and natural language interpreters can be implemented as extensions and embedded via a dedicated plug-in interface and configuration.

Dpdl is self contained, portable and highly customizable via a dedicated extensible interface.

For example the ROOT C++ Data Analysis framework from Cern is also available as Dpdl language plug-in.

Dpdl ( Java api + Embedded C + ‘C++’ + Python + Julia + JavaScript+ Lua + Ruby + Java + Clojure) = Powerful and Versatile

These features make Dpdl a powerful development platform for rapid prototyping, in particular also due to the fact that software written with Dpdl will be enabled to access thousands of existing high-quality software libraries.

Dpdl is not intended to replace, but to enable integration of different technologies seamlessly to leverage fast prototyping and facilitate research and development.

Dpdl is designed to:

Develop your ideas faster

On multiple platforms

Using the power of multiple programming languages and API’s

Reuse code

No need to install, compile and configure environments

Runs on constrained devices

Support for IoT protocols such as Bluetooth™ and CoAP

Compressing, query and handling data on constrained devices

* Self-contained, no additional dependencies required (except add-on libraries)

* Facilitate rapid prototyping for hardware programming

* Plug-in oriented

* Leverage prototyping with built-in AI generative code plug-in

DpdlEngine stack overview

Dpdl is designed to be Simple, Compact, Robust, Extensible and Portable to almost every platform

By combining the portability and vast API availability of Java and Python, the computational power of Julia, the web enablement of JavaScript, the expressiveness of Lua and Clojure, the simplicity of Ruby and the power of C/C++ programming language, Dpdl provides a powerful and versatile development platform for industrial applications, education and research.

Embedded ANSI C code and OCaml can also be dynamically compiled in memory at runtime in order to achieve faster execution performance.

This makes Dpdl suitable for a wide range of use-cases and in particular also for Hardware programming.

Common IoT protocol stacks such as Bluetooth™ and CoAP (Constrained Application Protocol) are supported by default and further protocols and functions can be added as easily as extensions.

The included Dpdl language plug-in ‘DpdlAINerd’ (DAN) makes use of AI generative code to enable to automatically generate and embedded executable code and content or data by natural language descriptions contained in Dpdl code.

Dpdl can be used as:

Dpdl can be used to encode, store, control and query data efficiently especially on small memory footprint devices and is foreseen to foster rapid application development. Dpdl comes with a very compact (ca. 650 Kb for DpdlEngine core + ANSI C interpreter/compiler) and portable scripting engine and an extensible API interface for the development of mobile applications and embedded system software.

The Dpdl language constructs and syntax is kept simple and follows an object oriented paradigm interoperable with the Java platform API and external java libraries.

Features

Dpdl JRE access

The provides API functions to load and access java objects and methods of the underlying JRE platform and of any other external java libraries. This allows to use a broad set of API’s within Dpdl.

Dpdl Example using external Java libraries

This is a sample Dpdl app implementing a 3D model visualization of chemical molecules using the JavaFX library. The model can be rotated freely with mouse events.

graphics/dpdl3DJavaFX_molecule.h

VIDEO of Dpdl sample 3D application

Dpdl embeddable languages

Multiple programming languages can be embedded within the same Dpdl code via the keyword >>.

Further programming languages can be developed and integrated via a dedicated plug-in interface and configuration. This enables basically every sort of programming language or natural language interpreter to be embedded directly in Dpdl code.

This features is very useful for rapid development and rapid prototyping and is also a key feature for generative software.

Currenlty the following programming languages are supported:

available add-on Plug-ins:

Dpdl Example with embedded ‘C’ and ‘JavaScript’ code

Sample Dpdl script with embedded ‘C’ code and javascript:

struct  A  {
	string id = "A"
	int  x = 10
	float f = 0.3
	double d = 0.4d
	object stro = loadObj("String",  "This is a java.lang.String object")

	func print()
		println("------------------")
		println("id: "  + id)
	end
}

# main
println("With Dpdl you can make use of any java library and embed different programming languages...")

struct A mya
mya.print()

println("creating a hashmap to store key/value pairs...")

object mymap = loadObj("HashMap")
mymap.put(1,  "Dpdl")
mymap.put(2,  "is")
mymap.put(3,  "Simple")
mymap.put(4,  "Compact")
mymap.put(5,  "Portable")

object keys = mymap.keySet()
object iter = keys.iterator()
object key, value
for(iter.hasNext())
	key = iter.next()
	value = mymap.get(key)
	println("key: "  + key +  " value: "  + value)
endfor

bool bcon = mymap.containsValue("Dpdl")
println("mymap contains 'Dpdl': "  + bcon)
println("")

println("Embed different programming languages directly..")
println("")

int n = 6
double x = 10.0d
string a = "test"
println("embedding C...")

dpdl_stack_push("dpdlbuf_var1",n, x, a)
>>c
#include <stdio.h>
#include <dpdl.h>

int main(int argc,  char  **argv){
	printf("Hello C from Dpdl!\n");
	printf("\n");
	printf("num  params: %d\n", argc);
	int cnt;
	for (cnt =  0; cnt < argc; cnt++){
		printf(" param %d: %s\n", cnt, argv[cnt]);
	}
	char *buf = "My result";
	dpdl_stack_buf_put(buf);
	return  0;
}
<<
int exit_code = dpdl_exit_code()
println("embedded C exit code: "  + exit_code);
string buf = dpdl_stack_buf_get("dpdlbuf_var1")
println("response buffer: "  + buf)
println("")

println("embedding javascript...")
int val = 23
arr[] = [1, 2, 3, 4]

dpdl_stack_push(val, arr)
>>qjs
console.log('Dpdl sends a message with js');
var sa;
var arr;
var v;
if(scriptArgs.length > 1){
	v = scriptArgs[0];
	sa = scriptArgs[1];
	arr = sa.split(",");
	std.printf("val=%d\n", v);
	console.log(arr);
}else{
	sa = "";
}

for(let i = 0; i < arr.length; i++)  {
	std.printf("arr[%d]=%d\n", i, arr[i]);
}
<<
int js_exit_code = dpdl_exit_code()
println("embedded javascript exit code: "  + js_exit_code);

Supported Platforms

Dpdl runs on a wide range of platforms and provides also a small footprint java virtual machine, released as Open-Source, that can be compiled for almost every platform as soon as an ANSI C compiler is available for the target platform.

‘DpdlEngine’ is compatible with:

So far DpdlEngine V1.0 has been tested on:

Roadmap

Dpdl is currently developed by SEE Solutions and the following integrations has been defined:

Documentation

The Dpdl framework and API documentation are available via the following links:

Dpdl Documentation

Dpdl API Documentation

Dpdl_embedded_languages

Dpdl embedded minimal C library Documentation

DpdlAINerd

Dpdl Examples

Visit official Dpdl-io repository on GitHub: DpdlEngine

Dpdl Examples

Dpdl-sample-Apps

Full features applications developed with Dpdl are published on this GitHub repository:

Dpdl-sample-Apps

Embedding of ‘ROOT C++’ code

ROOT is a powerful Data Analysis Framework developed by CERN (https://root.cern/) .

ROOT C++ code can be embedded within Dpdl via the keyord ‘>>root’

Example Dpdl script embedding ‘ROOT C++’:
Dpdl ROOT example

# main
println("test embedded ROOT C++...")

>>root
auto canvas = new TCanvas("c","Graph2D example",0,0,700,600);

double x, y, z, P = 6.;
int np = 200;
auto dt = new TGraph2D();
auto r = new TRandom();
for (int N=0; N<np; N++) {
	x = 2*P*(r->Rndm(N))-P;
	y = 2*P*(r->Rndm(N))-P;
	z = (sin(x)/x)*(sin(y)/y)+0.2;
	dt->SetPoint(N,x,y,z);
}
dt->Draw("tri1 p0");
canvas->Modified(); canvas->Update();
<<

int exit_code = dpdl_exit_code()
println("embedded ROOT exit code: " + exit_code)

Compress and decompress data using the Java Platform API

Dpdl example that uses java.util.GZIP* classes to compress and de-compress data

# main
object str = loadObj("String", "my data to compress")
println("string to compress: " + str)

object byte_out = loadObj("ByteArrayOutputStream")
object zip_out = loadObj("GZIPOutputStream", byte_out)

println("compressing...")
zip_out.write(str.getBytes("UTF-8"))
zip_out.close()
println("data compressed successfully!")

object compressed_str = byte_out.toString()
println("compressed string: " + compressed_str)

println("decompressing...")
object byte_in = compressed_str.getBytes("UTF-8")
object byte_arr_in = loadObj("ByteArrayInputStream", byte_in)
object byte_arr_in_obj = cast(byte_arr_in)
object zip_in = loadObj("GZIPInputStream", byte_arr_in_obj)

object in_reader = loadObj("InputStreamReader", zip_in)
object buf_reader = loadObj("BufferedReader", in_reader)

string decompressed_str = ""
string line = ""
while(line != null)
	line = buf_reader.readLine()
	if(line != null)
		decompressed_str = decompressed_str + line
	fi
endwhile

println("decompressed: " + decompressed_str)

Bluetooth device discovery

Example Dpdl script (Bluetooth device discovery using high level Dpdl API ):

int status = DPDLAPI_searchClientsOnServer()
int status_discovery = dpdlFalse
int service_discovery = dpdlFalse
int counter = 0
if(status == dpdlTrue)
	while (status_discovery != dpdlTrue) && (service_discovery != dpdlTrue)
		status_discovery = DPDLAPI_discoveryServerFinished()
		service_discovery = DPDLAPI_serviceDiscoveryServerFinished()
		print(".")
		counter = counter+1	
		sleep(3000)
	endwhile
	
	string dev = "n"
	int dev_found = 0
	while(dev != "null")
		dev = DPDLAPI_getServerVisibleBTAddr()
		if(dev != "null")
			println("bluetooth device visible: " + dev)
			saveData(dev)
			dev_found = dev_found + 1
		fi
	endwhile
else
	println("No working Bluetooth stack found")
fi

Embedding of Python code

Python code can be embedded within Dpdl script by using the keyword ‘>>python’.

Example Dpdl script with embedded ‘Python’ code:

println("testing embedding python code wihin Dpdl")
println("")

>>python
languages = ['Dpdl', 'C', 'Python', 'OCaml']
for language in languages:
	print(language)
<<
# again Dpdl
println("")
int exit_code = dpdl_exit_code()
println("ebedded python exit code: " + exit_code);

Embedded C code

Dpdl allows the embedding and on-the-fly execution of ANSI C code directly within Dpdl scripts.
The C code can be executed with 2 Modes, either interpreted only OR compiled in memory at runtime (if option ‘dpdl:compile’ is enabled), via a native Dpdl library that has a very small footprint and includes all essential C libraries and language constructs (ISO standard C90/C99, POSIX compliant) with no external dependencies.

Custom libraries and functions can be integrated and linked via a straight forward implementation configuration approach.

Example Dpdl script with embedded C code:

# main
# starting with Dpdl, pushing parameters on the stack and embedding C code

println("testing embedded C code in Dpdl")
int n = 6
double x = 10.0
string a = "test"
dpdl_stack_push(n, x, a)
>>c
#include <stdio.h>

int main(int argc, char **argv){
	printf("Hello C from Dpdl!\n");
	printf("\n");
	printf("num params: %d\n", argc);
	int cnt;
	for (cnt = 0; cnt < argc; cnt++){
		printf(" param %d: %s\n", cnt, argv[cnt]);
	}
	return 0;
}
<<
# again Dpdl...
int exit_code = dpdl_exit_code()
println("embedded C exit code: " + exit_code);

object str = loadObj("String", "Dpdl embedded C")
bool b = str.contains("C")
println("Dpdl contains C: " + b)

This is a more complete example of the usage of embedded C code within Dpdl:

dpdlEmbeddedC.h

Embedding of ‘Julia’

Julia is a powerful and performant computational programming language (https://julialang.org)

Julia code can be embedded within Dpdl via the keyord ‘>>julia’

Example Dpdl script embedding ‘Julia’ that generates a Plot and saves it as PDF:

Dpdl ROOT example

#main
println("Testing Plot data with Julia programming language...")

>>julia
using Plots

x = range(0, 10, length=100)
y1 = sin.(x)
y2 = cos.(x)
p = plot(x, [y1 y2])

savefig(p, "./Test/myplot.pdf")

dispose_status = @ccall dpdl_julia_dispose()::Int32
return 1
<<

int exit_code = dpdl_exit_code()
println("finished with exit code: " + exit_code)

Other programming languages

Other programming languages or natural language interpreters can be easily integrated in Dpdl via a dedicated plug-in interface and configuration. Please feel free to suggest yours favorite language on the Discussion section on the DpdlEngine GitHub repository

More Examples

Dpdl_Examples.md

Download free trial ‘DpdlEngine lite’

The ‘DpdlEngine lite’ release can be downloaded as Free trial shareware (with some limitation/restrictions) from the following download request form:

Download Request Form

How to buy a ‘full’ DpdlEngine license?

To buy a full featured ‘DpdlEngine lite’ license with no limitations/restrictions, regular updates and support, please submit your request via the following request form:

Order Request Form

For custom requirements or a bulk reseller license write an e-mail to the contact address.

Contact

e-mail: info@dpdl.io