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Is it possible to change at runtime a specific value inside a property.file in spring boot?

I'm developing an API which will connect with several endpoints. The uri for each endpoint is something like this:
rest/services/General/directory1/MapServer/export
rest/services/General/directory2/MapServer/export
rest/services/General/directory3/MapServer/export
rest/services/General/directory4/MapServer/export
and so on...
I don't know if it's possible, but would like to have something like this instead:
rest/services/General/${value}/MapServer/export
and then on my code just call the endpoint above injecting the specific directory that I want on ${value}
Is it possible? Don't know what I'm missing as I googled but couldn't find anything related.
Cheers

You can do so by means of Spring Cloud Config.
Spring Cloud Config provides server and client-side support for
externalized configuration in a distributed system. With the Config
Server you have a central place to manage external properties for
applications across all environments. The concepts on both client and
server map identically to the Spring Environment and PropertySource
abstractions, so they fit very well with Spring applications, but can
be used with any application running in any language. As an
application moves through the deployment pipeline from dev to test and
into production you can manage the configuration between those
environments and be certain that applications have everything they
need to run when they migrate. The default implementation of the
server storage backend uses git so it easily supports labelled
versions of configuration environments, as well as being accessible to
a wide range of tooling for managing the content. It is easy to add
alternative implementations and plug them in with Spring
configuration.
For more details, kindly go through spring documentation here.

I solve the problem using the simplest approach possible. In my code I used the string.replace() method. Was looking for something more robust, but as it was taking lots of time to sort it out how to do it, I decided to go with the string.replace method.

Oracle/Java application, recommended architectures

I am working on a desktop Java application that is supposed to connect to an Oracle database via a proxy which can be a Servlet or an EJB or something else that you can suggest.
My question is that what architecture should be used?
Simple Servlets as proxy between client and database, that connects to the database and sends results back to the client.
An enterprise application with EJBs and remote interfaces to access the database
Any other options that I haven't thought of.
Thanks

Depending on how scalable you want the solution to be, you can make a choice.
EJB (3) can make a good choice but then you need a full blown app server.
You can connect directly using jdbc but that will expose url of db (expose as in every client desktop app will make a connection to the DB. you can not pool, and lose lot of flexibilities). I would not recommend going this path unless your app is really a simple one.
You can create a servlet to act as proxy but its tedious and not as scalable. You will have to write lot of code at both ends
What i would recommend is creating a REST based service that performs desired operations on the DB and consume this in your desktop app.

Start off simple. I would begin with a simple servlet/JDBC-based solution and get the system working end-to-end. From that point, consider:
do you want to make use of conenction pooling (most likely). Consider C3P0 / Apache DBCP
do you want to embrace a framework like Spring ? You can migrate to this gradually, and start with using the servlet MVC capabilities, IoC etc. and use more complex solutions as you require
Do you want to use an ORM ? Do you have complex object graphs that you're persisting/querying, and will an ORM simplify your development ?
If you do decide to take this approach, make sure your architecture is well-layered, so you can swap out (say) raw JDBC in favour of an ORM, and that your development is test-driven, such that you have sufficient test cases to confirm that your solution works whilst you're performing the above migrations.
Note that you may never finalise on a solution. As your requirements change, and your application scales, you'll likely want to swap in/out the technology most suitable for your current requirements. Consequently the architecture of your app is more important than the particular toolset that you choose.

Direct usage of JDBC through some ORM (Hibernate for example) ?
If you're developing a stand-alone application, better keep it simple. In order to use ORM or other frameworks you don't need a J2EE App Server (and all the complexity it takes with it).
If you need to exchange huge amounts of data between the DB and the application, just forget about EJBs, Servlets and Web Services, and just go with Hibernate (or directly with plain old JDBC).
A REST based Web Services solution may be good, as long as you don't have complex data, and high numbers (try to profile how long does it takes to actually unmarshal SOAP messages back and to java objects).

I have had a great deal of success with using Spring-remoting and a servlet based approach. This is a great setup for development as well, since you can easily test your code without deploying to an web container.
You start by defining a service interface to retrieve/store your data (POJO's).
Create the implementation, which can use ORM, straight JDBC or some pooling library (container provided or 3rd party). This is irrelevant to the remote deployment.
Develop your application which uses this service directly (no deployment to a server).
When you are satisfied with everything, wrap your implementation in a war and deploy with the Spring DispatcherServlet. If you use maven, it can be done via the war plugin
Configure the desktop to use the service via Spring remoting.
I have found the ability to easily develop the code by running the service as part of the application to be a huge advantage over developing/debugging something running on a server. I have used this approach both with and without an EJB, although the EJB was still accessed via the servlet in our particular case. Only service to service calls used the EJB directly (also using Spring remoting).

Best architecture for applications in GWT

I'm starting to study GWT now, and have a very general question, I could maybe teach myself with a little more experience, but I don't want to start it wrong, so I decided to ask you.
I always develop using JSF, having separate packages for beans, controllers and managedbeans.
However, as the GWT uses RPC, I will not have managedbeans, right?
So, GWT automatically handles user session for me, or do I have to do it myself?
What is the best package structure for the project?
It is best to use RPC, or create a webservice and access the webservice in GWT?
It's hard to host the application on a tomcat server?
Is there a test saying which server is faster for GWT?
Thank you.

However, as the GWT uses RPC, I will not have managedbeans, right?
True, GWT RPC uses POJOs.
So, GWT automatically handles user session for me, or do I have to do it myself?
GWT is pure AJAX APP - client code (normally) runs in one browser window (similar to gmail) and does not reload the web page. This means that the application state is always there - no need for sessions (as a means of saving state). You still might need sessions for user authentication, but this is usually handled by servlet container.
What is the best package structure for the project?
Three packages: client, server and shared. Client for GWT client code, server for server (also RPC) code and shared for POJOs that are used by both client and server.
It is best to use RPC, or create a webservice and access the webservice in GWT?
Go with GWT-RPC or (better, newer) with RequestFactory.
It's hard to host the application on a tomcat server?
It's straightforward: GWT client code is compiled to JS/html and is hosted as any static content. RPC server code is just Servlets - normal web.xml registration.
Is there a test saying which server is faster for GWT?
No clue, but IMHO does not matter, because most of the latency will come from database and network.

Also have a look at http://code.google.com/p/gwt-platform/
This framework is really great and follow all suggested best practices(e.g. MVP) by google and give you as well great support for gin, gwt dispatcher, website crawling, history with tokens, code splitting via gwt async etc.
If you want to set up a good project structure try to use the maven gwt plugin(http://mojo.codehaus.org/gwt-maven-plugin/) it helps you a lot with setting up an initial structure and manage your build process.

Axis2 POJO Web Services

I have a POJO which is being deployed as a webservice in Axis2 - Tomcat combo. What is the best way to supply runtime configurations to the service? All servcie related config parameters are in XML file -
What's the best location to keep this config file? Note I want the service to be completely self contained.
How do I get the physical location of the service home i.e. Tomcat 6.0\webapps\axis2\WEB-INF\services\MyService?
How good is Axis2 i.e. is it a good choice to select Axis2 as webservice platform? The project is with aggressive timelines (what's new? :)) so really do not wish to dive into the Contract First etc stuff. Need a quick solution where I can drop in POJO and use it as webservice.
As always, Your help is very much appreciated!

I used JNDI to control the runtime configuration options for simple web services. How to configure JNDI depends on the container you are using, Jetty/Tomcat etc.
More complicated projects I embed spring and manage both configuration and other persistent objects.
Axis2 is a good platform for developing stand-alone web services. I'd still recommend having a look at contract first stuff. It is of course more complicated but gives more control over the XML messages exchanged between client and server. The neat thing about Axis2 is that you can start with POJOs and get more complicated later.

Note I want the service to be completely self contained.
Do u mean u would like to move this modules on other container ... which do not support TOMCAT based dir structure...... bit difficult
If Axis hosting concern is of TOMCAT alone then the best way to use the configurations is via an Property /XML file stored at the root of the Java package and haven a Startup servlet with load on startup 1 to read the property file using
context.getRealPath("") + "/WEB-INF/classes/abcd.xml" or
context.getRealPath("") + "/WEB-INF/classes/abcd.propertyfile
Store the same in a key /value based Hashtable ...further store the Hash table in Servletcontext.
On any where required fetch the Valu by passing the Key to the Hash table and use the same.
However the startup servlet should run Once only only by using Load on startup tag in web-xml ...
hope this helps

Creating a REST webserver with security

I am very new to creating webservers - and I have had several goes at trying to understand them and write a quick webserver, but it's never quite 'clicked'. At the moment I am under the impression that REST would be most suitable for my purposes (I will explain later).
Can anyone either show me a basic code example in Java (using Tomcat Apache) or a tutorial resource to show how a webserver:
Can be used for security - i.e. pass in some kind of value to identify the client - from their the webserver will either deny or grant access to the client dependant on some criteria - maybe a lookup list.
Once the client is successfully accepted they will be allowed to pass in some more values to the webserver that will be used to write a row in a database table.
Many thanks.
PS - I would have thought there might have been soemthing that comes with Eclipse Ganymede? If someone can confirm?

The best way to write restful resources in Java is via the JAX-RS standard. So I'd recommend you download Jersey which is the JAX-RS reference implementation and check out its examples; its got lots of them. Take an example for a spin then try hacking it to do what you like.
BTW JAX-RS can be run inside any Servlet engine - you just build a WAR and deploy it (there are examples in the Jersery samples) - though Jersey also comes with a small lightweight web server you can use too which is a little easier to use - again there are examples in the distro of this.

I would also suggest that you look at Restlet