Re: The Revenge of the Geeks

From: BGB <cr88192_at_hotmail.com>
Date: Sat, 26 Jan 2013 12:40:18 -0600
Message-ID: <ke1811$g4n$1_at_news.albasani.net>

On 1/26/2013 5:25 AM, Arved Sandstrom wrote:
> On 01/26/2013 01:31 AM, BGB wrote:
>> On 1/25/2013 9:05 PM, Arne Vajhøj wrote:
>>> On 1/24/2013 11:31 PM, BGB wrote:

>>>> On 1/24/2013 9:15 PM, Arne Vajhøj wrote:

>>>>> On 1/24/2013 10:10 PM, BGB wrote:
>>>>>> On 1/24/2013 4:58 PM, Arne Vajhøj wrote:
>>>>>>> On 1/24/2013 5:10 PM, BGB wrote:
>>>>>>>> On 1/24/2013 10:06 AM, Arne Vajhøj wrote:
>>>>>>>>> On 1/23/2013 11:47 PM, BGB wrote:
>>>>>>>>>> but, in any case, with the other languages there are a wide
>>>>>>>>>> range of
>>>>>>>>>> libraries available, many under fairly open licenses (like MIT or
>>>>>>>>>> BSD),
>>>>>>>>>> and there is a lot more GPL stuff available,
>>>>>>>>>
>>>>>>>>> In the EE space you would need to look at CORBA or DCOM.
>>>>>>>>>
>>>>>>>>> You would prefer Java EE believe me.
>>>>>>>>>
>>>>>>>>> :-)
>>>>>>>>>
>>>>>>>>
>>>>>>>> errm, so you can't just copy all the files over to ones' servers?
>>>>>>>> and/or
>>>>>>>> recompile the code for ones' servers?...
>>>>>>>
>>>>>>> The coding model in Java EE is definitely more modern than that
>>>>>>> of CORBA and DCOM.
>>>>>>>
>>>>>>
>>>>>> I didn't mean like CORBA or DCOM, but probably directly copying over
>>>>>> program binaries (DLLs or SOs and precompiled binaries and similar),
>>>>>> and
>>>>>> probably using traditional compilation and linking.
>>>>>
>>>>> You lost me.
>>>>>
>>>>> How to get the same type of services as Java EE provides is related
>>>>> to copying binaries how?
>>>>

>>>> I may be missing something here...

>>>>

>>>> because... it involves linking against and using libraries, correct?...

>>>>

>>>> like "both languages have libraries, but maybe not the same libraries".

>>>>

>>>> as in, for Java, you can copy around and use a JAR.
>>>> or in C or C++, you link against the DLL or SO, or use a static-library
>>>> (which then becomes a permanent part of the binary), ...

>>>>

>>>> like, for Java there is LWOGL, and for C there is "opengl32.dll".
>>>> or, one person uses AWT or Swing, and another uses GDI+ or WinForms.

>>>>

>>>> if you have some program and need to run it on a web-server, it can be
>>>> copied over into its "cgi-bin/" directory or similar, or set it to run
>>>> at start-up as a deamon (or a as a service on Windows, or launch it via
>>>> "start-up applications" or similar).

>>>>

>>>> if end users run a program, they typically download it off the
>>>> internet,
>>>> maybe as a ZIP, or maybe as a self-extracting "setup.exe" or similar.

>>>>

>>>> any libraries would be contained inside, and copied over into the
>>>> relevant directories. any data files are typically copied along as
>>>> well,
>>>> and the installer might put everything in its place.

>>>>

>>>> and, if a person needs new libraries for a project they are developing,
>>>> they will go and download them off the internet, maybe recompile it
>>>> from
>>>> source, ...

>>>
>>> You copy jar files in Java EE just like you do in Java SE.
>>>
>>> The difference is in what the libraries do. Not how they are
>>> distributed.
>>>
>>
>> yes, ok.
>>
>>

>>>> I actually have little idea how DCOM or CORBA fits into this, as they
>>>> are network protocols (like for doing RPC),

>>>
>>> They are not.
>>>
>>> CORBA is a component model that uses IIOP as network protocol.
>>>
>>> DCOM is a component model that uses ncacn_tcp as network protocol.
>>>
>>
>> fair enough...
>>
>> I haven't really used either of them personally, FWIW.
>>
>> I will assume then that they are probably for inter-operation with other
>> servers or similar?
> [ SNIP ]
>
> Both CORBA and DCOM are meant for distributed applications. Like Arne
> said, both have to do with software components on numerous different
> machines, possibly different languages, and having defined interfaces
> for RPC. Myself I wouldn't even use the term "server" to explain what
> DCOM and CORBA do, not at a high level.
>

if it is on a different machine, and is providing something for being accessed over a network, wouldn't that machine be by definition a server?

>>>> but, for most client/server apps I am familiar with are more like:
>>>> server runs somewhere (opening a listen port, for example, port 80 for
>>>> HTTP, ...);
>>>> user downloads and runs client;
>>>> client opens socket to connect to server (such as TCP or UDP);
>>>> then they share whatever data is relevant over the socket, using the
>>>> relevant protocol (often application-specific).

>>>>
> [ SNIP ]
>>>
>>> Let me give you a very simple example.
>>>
>>> You want to allow browsers to connect to your code and be
>>> told what the time is.
>>>
>>> You could write that in Java SE. You listen on port 80, accept
>>> a connection, start a thread that parse the request and outout
>>> the response.
>>>
>>> With Java EE you could write now.jsp:
>>>
>>> <%=new Date()%>
>>>
>>> and Java EE would handle sockets, threads, reading and writing for
>>> you.
>>>
>>> The JSP get compiled to Java that get compiled to byte code that
>>> get JIT compiled.
>>>
>>
>> ok, so it does something sort of like a web-server then, but with Java
>> taking the role of PHP or similar?
>>
>> I guess maybe that has to do with the whole "application server" thing,
>> which was another part I didn't really understand what it was doing
>> exactly...
> [ SNIP ]
>
> Don't make the mistake of thinking that Java EE == web application.
> Although I expect that a lot of Java coders who write only web apps in
> the Java EE space may get to thinking that way.
>
> Your typical Java EE enterprise app running on top of a Java EE
> application server may or may not have a web tier. Just like servers
> written in other languages on other platforms may often also have
> nothing whatsoever to do with HTTP and HTML and web browsers.
>
> But I suppose if you look at the numbers of Java EE app deployments,
> I'll speculate that the very large majority are web apps or at least
> incorporate one.
>

ok, but all this is still a bit outside my area.

> Since you mentioned PHP, and Arne mentioned JSP, you're aware that you
> might run a PHP app on Apache with mod_php. Think of that latter as
> being your app server. Similarly, if you want to run an ASP.NET MVC app,
> you might set up an IIS website for it - IIS is your app server. In the
> case of Java EE web apps using JSP as a view technology (with or without
> JSF in the picture) then a Java EE server is your application/web server.
>

I think I may have enabled mod_php, partly as IIRC the MediaWiki installation instructions said to do something like this (along with which things to install, ...).

I have not personally messed with IIS or ASP.NET.

the vast majority of code I have written in C# has been either small tools (command-line or sometimes with a GUI), or Paint.NET plugins. Received on Sat Jan 26 2013 - 19:40:18 CET