How similar are packages in PL/SQL and the classes in C++ ? I am getting to know about packages for the first time and their arrangement and constitution using procedures and functions reminded me of classes in C++ .But at the same time I guess there are differences between these two .I guess , inability to create objects of packages as we can do in case of class is one of them . I wanted to know what are the similarities and differences between packages and class . Are packages, by any chance meant for replicating object oriented programming in PL/SQL ?
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I am having to do some Java work, having been immersed in .Net/C# for many years. I used to think that a Package was equivalent to a .Net assembly or dll - other SO qus that suggest this get a flat "no" - not the same, and yet the word "package" strongly suggests a packed something that could be shared around.
So, in Java, what IS the equivalent of the shareable DLL/project/assembly/class library? In .Net it is standard practice to reference another local project or a DLL built elsewhere. If I wanted to market MyWonderfulLibrary in .Net, I might deliver a DLL file. Equivalent in Java - a jar file? Is this always called an "archive"? Archive suggests something put away for safe-keeping and rarely accessed....
I'm having problems coming to terms with the terms, so to speak. Does Bean = Class? - another source of confusion...
There is a lot of info on comparing the languages, but any guidance or info that compares/clarifies common terminology in .Net projects and Java "projects" (?) would be much appreciated.
I know the Wordnet webpage cites that it comes with a C interface included. However, I am having significant trouble adding it to my project. My question is two fold.
First: Does a machine need to have wordnet installed to utilize the API (or can the data be read a runtime from the dict files? and thus distributed to machines that do not have wordnet installed)
Second: How can you include Wordnet in a C project. I've tried adding the source files directly, but it crashes on init(). I've stepped through the debugger and it looks like it is looking to load the files from my local drive rather than the included files in the project. Is there a way to prevent this for machines that do not have Wordnet installed (from part 1).
Thank you for the help,
Unless I'm mistaken and you're referring to a different WordNet, there has been a Cocoa front-end available for years here.
Just found this today. Might be helpful, as it only requires adding the sqlite.db file of WordNet and provides a super super thin Objective-C wrapper on the sqlite call to talk to the database. Using this as a template for your understanding should allow you to extend it to allow various queries.
https://gist.github.com/atduskgreg/c30a5fb167f4c35d6f89
EDIT: With the above example, you can see the format the query takes. With that knowledge, you could grab the sqlite file for the WordNet database from:
https://code.google.com/p/synonym/downloads/detail?name=wordnet30.1.tar.gz&can=2&q=
then either just use the C calls for sqlite or pick a more robust Objective-C wrapper like:
https://github.com/ccgus/fmdb
I'm fairly new to programming and wanted to start programming more efficiently. Try as I may I often find myself straying from the MVC model.
I was wondering are there any tips or methods in keeping your code organized when coding in xcode objc? To be more specific (I know you guys like that :) I want to
Be able to write libraries or self-containing code that can bring from one project to another
Share my code with others as open sourced projects
Prevent myself from writing messy code that does not follow proper structure
Use a high warning level. Build cleanly.
Remove all static analyzer issues.
Write some unit tests.
Keep the public interfaces small.
Specify your library's dependencies (e.g. minimum SDK versions and dependent libraries).
Compile against multiple/supported OS versions regularly.
Learn to create and manage static library targets. This is all you should need to support and reuse the library in another project (unless you drag external resources into the picture, which becomes a pain).
No global state (e.g. singletons, global variables).
Be precise about support in multithreaded contexts (more commonly, that concurrency shall be the client's responsibility).
Document your public interface (maybe your private one too…).
Define a precise and uniform error model.
You can never have enough error detection.
Set very high standards -- Build them for reuse as reference implementations.
Determine the granularity of the libraries early on. These should be very small and focused.
Consider using C or C++ implementations for your backend/core libraries (that stuff can be stripped).
Do establish and specify any prefixes for your library's objc classes and categories. Use good prefixes too.
Minimize visible dependencies (e.g. don't #import tons of frameworks which could be hidden).
Be sure it compiles without the client needing to add additional #imports.
Don't rely on clients putting things in specific places, or that resources will have specific names.
Be very conservative about memory consumption and execution costs.
No leaks.
No zombies.
No slow blocking operations on the main thread.
Don't publish something until it's been well tested, and has been stable for some time. Bugs break clients' code, then they are less likely to reuse your library if it keeps breaking their program.
Study, use, and learn from good libraries.
Ask somebody (ideally, who's more experienced than you) to review your code.
Do use/exercise the libraries wherever appropriate in your projects.
Fix bugs before adding features.
Don't let that scare you -- it can be really fun, and you can learn a lot in the process.
There are a number of ways you can reuse code:
Store the code in a common directory and include that directory in your projects. Simple, but can have versioning issues.
Create a separate project which builds a static iOS library and then create a framework. More complex to setup because it involves scripting to build the framework directory structure. But easy to use in other projects and can handle versioning and device/simulator combined libs.
Create a separate project which builds a static iOS library and then include this as a subproject in other projects. Avoids having to build frameworks and the results can be more optimised.
That's the basic 3, there are of course a number of variations on these and how you go about them. A lot of what you decide to do is going to come down to who you are going to do this for. For example I like sub projects for my own code, but for code I want to make available for others, I think frameworks are better. even if they are more work to create. Plus I can then wrap them up with docsets of the api documentation and upload the whole lot as a DMG to github for others to download.
I could use a little advice on naming my assemblies
(ie. When to turn a logical naming convention in my
namepaces into its own DLL).
I recently downloaded an example project with a ton of
class libraries in it that almost exactly mirrored the
namespaces.
To date, I have been building one massive class
library - MyProject.DLL - and referencing it in my
project. This way, I only need one library and can
access all namespaces using it.
But, in the project I downloaded, there seems to
be a DLL for every namespace (and, in some cases,
subcategoreis within a namespaces. For example,
SomeProj.Web.Security has SomeProj.Web.Dll and
SomeProj.Web.Security.Dll).
I understand that having multiple DLLs can make
it easier to focus on particular areas of the project
(and, probably, updating the DLL withing the site
easier) but is there a best practice here?
Thanks in advance...
OK, this pretty much answers my question:
http://msdn.microsoft.com/en-us/library/ms229048.aspx
I recently ran across this open-source project: http://www.codeplex.com/Sculpture
Sculpture is a code-generator which allows you to design your domain model and then use persistence 'molds' such as NHibernate/EF and probably more to generate repositories. It takes care of all the mapping and Data access generation. It looks like it does a heck of a lot more, but i'm pretty much sold at this point. However, i would like to know if anyone here used this for real-world solutions. If so, how well does it scale? How did the generated DAL work for you?
We have taken this out for a spin on a new project we had. Always wanted to try out nHibernate but the XML hell of the config files always put me off. Tried a number of these type "helpers" this is the easiest to use so we decided to use it.
I like the facts that you can just point at databse and it will create object based on what it sees and will resync on demand. It was also good that you could add custom methods to these objects and has a very well written syntax for the generated code all using LINQ-To-NHibernate.
It also generated a respository project over the top to allow you to use this design pattern which we did (again another personal goal).
It all worked out very well, created a social (facebook like) site for people with a medical condition, got everything fully working in 3 weeks with onlt 3 people.
On the whole very happy with this - in fact bought a licence for Sculpture 2.1 Nhibernate mold. (note open source but not for nhibernate mold :-) )
There is room for improvement
Windows 7 64 bit had to run visual studio in admin mode (my pc only) - not sure why
TeamCity continuous integration had some issues with paths to dll files - the two generated project (ORm and Repository) use different paths to base dll's - so needed to work out position of source in filestore to automate the build but worked fine.
Would like to heard any views on this or other product which people think are better ..
Looking to do a project where we will create all the objects in sculture and get it to produce/update the database for us - will be odd as we are db type developers but will be good to see how this works..
Thanks
Simon
I would say that most ORMs are generated in some way at this point. I'm using Linq-to-SQL for a current project, you setup your model and generate code (with attributes from the model).
In short, it's nothing new and there's no reason to rebuff it just because it's generated.
Most ORMs can or do work this way, and they do so well.