David Garratt

I have zero experience of talking to PLC's and my Java knowledge is primarily desktop java apps. I need to incorporate comms to a PLC and some barcode scanners/sensors via a PLC. I've done a little googling but the approach to use is far from clear. At the moment I have come across one candidate which is the Eclipse Milo project. However I would like to keep it as simple as possible and don't really relish having to deploy other frameworks like Apache Camel or Spring Boot in order to use Eclipse Milo. I am more thank willing to admit my knowledge in this arena is very limited so I would welcome a push in the right direction to save time with dead ends. It would be my preference to keep my project open source but if those 3rd open source libraries are not mature yet then any recommendations would be welcome.

I'm trying to keep this question as concise as possible as I don't want to steer any responses down any specific routes by accident. I anticipate that the data that I will want from a PLC via whatever means will be a barcode string indicating a works order number and another boolean/integer flag which indicates that a pallet is in position and a print is required. I'm not sure if I can get some kind of event driven notification that data has changed or if I will have to keep polling.

At this stage I'm sorry I cannot be more specific but if anyone has done this with a java client app and can give me some pointers it would be most appreciated.

It's all clear for me now. I had assumed the file at the top was a binary program when in fact is it a script and will then of course run on a M1 Mac.

Thanks anyway

Dave

I think I will soon need counselling before I figure out how to get everything working on an Apple Silicon Mac.

You would think it would be simple - all I want is a version of Eclipse with runs natively on the mac (arm based) and can run both WindowBuilder and JasperStudio plugins - ahhh no chance.

Eclipse for arm is based on Java 17 - but Jasper plugin fails and needs Java 16.  No idea about windowbuilder yet but I suspect I will be using rosetta 2 and emulation for some time.

There does not seem to be an arm build of Eclipse for Java 16.

hoo hum, thanks for everyone's help.

Dave

Ok - I understand now.

Thank you

Dave

Tim Holloway wrote:And, incidentally, this also applies to Maven and probably Gradle (I haven't checked that one, though).

The essential parts of Tomcat are likewise "write-once/run-anywhere".

Sorry - do you means it's all java or are you referring to the presence of what I assume is a intel binary ?

When I unzip the ant binary download on my mac I see a file called ant which is described as a linux binary and I assume that providing this folder is on my path that this is what is running when I type "ant" at the terminal prompt ?

These are the files I see in the ant folder

-rwxr-xr-x@ 1 dave  staff  11730 10 Jul 19:36 ant
-rw-r--r--@ 1 dave  staff   7471 10 Jul 19:36 ant.bat
-rw-r--r--@ 1 dave  staff   2856 10 Jul 19:36 ant.cmd
-rwxr-xr-x@ 1 dave  staff    862 10 Jul 19:36 antRun
-rw-r--r--@ 1 dave  staff   1533 10 Jul 19:36 antRun.bat
-rwxr-xr-x@ 1 dave  staff   2118 10 Jul 19:36 antRun.pl
-rw-r--r--@ 1 dave  staff   3410 10 Jul 19:36 antenv.cmd
-rwxr-xr-x@ 1 dave  staff   3459 10 Jul 19:36 complete-ant-cmd.pl
-rw-r--r--@ 1 dave  staff   4316 10 Jul 19:36 envset.cmd
-rw-r--r--@ 1 dave  staff   1113 10 Jul 19:36 lcp.bat
-rwxr-xr-x@ 1 dave  staff   4167 10 Jul 19:36 runant.pl
-rwxr-xr-x@ 1 dave  staff   3344 10 Jul 19:36 runant.py
-rw-r--r--@ 1 dave  staff   1815 10 Jul 19:36 runrc.cmd

Has anyone tried using ANT on a new Apple Silicon M1 based mac ?

I cannot seem to find any arm builds at all and was wondering if I'm either not looking in the right place or if the Rosetta 2 emulation works ok.

Dave

We did have a happy ending to my ticket - despite my lack of technical knowledge however.

We found out that if you tell Eclipse to use Safari rather than it's own internal browser the problem goes away.

They are going to continue to investigate and see if it can be resolved in the next release but at least I have a good workaround.

Thanks

Dave

I don't specifically want to use https - it's merely an attempt to work around a problem described here https://bugs.eclipse.org/bugs/show_bug.cgi?id=574611

On MacOS Big Sur running Eclipse 2021 06 or 09 - if I select my "web app" and say "run on server" you get this error message.

Page load failed with error: The resource could not be loaded because the App Transport Security policy requires the use of a secure connection.

Your suggested plugin lets you stop and start Tomcat but I want to be able to set a breakpoint in my web app code and step through it.

I am now trying to run my Tomcat 9 server using HTTPS and enabling remote debug to see if that will allow me to work around the security blocking message.

Dave

So if I understand you I need to setup my separate tomcat server to support https as well as http. I can then delete my existing tomcat definition within eclipse, install this plugin from the marketplace and then add back the tomcat server from within eclipse. I’m not near my computer at the moment but is there some alternative way of selecting my servlet to run or debug using the new plugin instead of my current method which seems to only support http.

Thanks for your help.

Dave

Are you referring to this plugin - https://sourceforge.net/projects/mongrel/files/Eclipse%20Plugin/ - 10 years old ?

From Eclipse 2021 06 and 09 versions if I try and run or debug a servlet within eclipse against a local Tomcat instance I get the following error. (Running on MAcOS)

http://localhost:8080/b5web/ Page load failed with error: The resource could not be loaded because the App Transport Security policy requires the use of a secure connection.

Eclipse 2021 03 does not have this issue but I would like to see if there are some workarounds which will let me use the later versions. I have had some temporary limited success modifying the Apple plist.info file within the Eclipse image file but it usually decides that the program is corrupt and won't let me run it after a while.

I know how to deploy the .war file manually and run the application but I still really need to be able to debug the servlet and trace through its execution.

I would really welcome some alternatives to help me continue to use Eclipse and debug my servlets. There is a known bug report which I've filed on this subject https://bugs.eclipse.org/bugs/show_bug.cgi?id=574611 but there is no timescale for a fix.

Many thanks

Dave

I had to revert to the 2021 03 version of Eclipse until the bug has been fixed in the 2021 06 verson. See link in previous post.

https://bugs.eclipse.org/bugs/show_bug.cgi?id=574611

As per my first post I'm using Java 11 and Apache Tomcat 9 but these have not changed for some time.

I'll have a look and see if I can use your plugin.

Thanks

Dave