automatic GWT ClientBundles based on disk files - gwt

I'm currently making good use of GWT's ClientBundles in my app. It works fine, but I have a large number of resources and it becomes tedious to manually create Java interfaces for each file:
#ClientBundle.Source("world_war_ii.txt")
public ExternalTextResource worldWarII();
#ClientBundle.Source("spain.txt")
public ExternalTextResource spain();
#ClientBundle.Source("france.txt")
public ExternalTextResource france();
I'd like to be able to (perhaps at compile time) dynamically list every *.txt file in a given directory, and then have run-time access to them, perhaps as an array ExternalTextResource[], rather than having to explicitly list them in my code. There may be hundreds of such resources, and enumerating them manually as code would be very painful and unmaintainable.
The ClientBundle documentation explicitly says that "to provide a file-system abstraction" is a non-goal, so unfortunately this seems to disallow what I'm trying to do.
What's the best way to deal with a large number of external resources that must be available at run-time? Would a generator help?

There's an automatic generator for CssResource - maybe you could look at its code and modify it to your needs?

I ended up following this advice: perform the file operations on the server, and then return a list of the file (meta)data via an RPC call.
This turns out to be fairly simple, and also allows me to return lightweight references (filenames) in the list, which I use to populate a Tree client-side; when the user clicks on a TreeItem the actual text contents are downloaded.

Related

zend framework own functions and classes

Now I have some experience in using the Zend Framework. I want to go deeper in the topic and rewrite some old php projects.
What is the best place to save own functions and classes?
And how do I tell Zend where they are? Or is there already a folder for own stuff? May I have different folders for different files?
For example I want to save a php document with the name math_b.php which includes several special functions to calculate and another one date_b.php which has abilities for datetime stuff. Is that possible or shall I have different files for every function?
I would also like to reuse the functions in other projects and then just copy the folders.
There is no single "right" answer for this. However, there are several general guidelines/principles that I commonly employ.
Do not pollute global scope
Namespace your code and keep all functions is classes. So, rather than:
function myFunction($x) {
// do stuff with $x and return a value
}
I would have:
namespace MyVendorName\SomeComponent;
class SomeUtils
{
public static function myFunction($x)
{
// do stuff with $x and return a value
}
}
Usage is then:
use MyVendorName\SomeComponent\SomeUtils;
$val = SomeUtils::myFunction($x);
Why bother with all this? Without this kind of namespacing, as you bring more code into your projects from other sources - and as you share/publish your code for others to consume in their projects - you will eventually encounter name conflicts between their functions/variables and yours. Good fences make good neighbors.
Use an autoloader
The old days of having tons of:
require '/path/to/class.php';
in your consumer code are long gone. A better approach is to tell PHP - typically during some bootstrap process - where to find the class MyVendor\MyComponent\MyClass. This process is called autoloading.
Most code these days conforms to the PSR-0/PSR-4 standard that maps name-spaced classnames to file-paths relative to a file root.
In ZF1, one typically adds the ./library folder to the PHP include_path in ./public/index.php and then add your vendor namespace into the autoloaderNameSpaces array in ./application/config.ini:
autoloaderNameSpaces[] = 'MyVendor';
and places a class like MyVendor\MyComponent\MyClass in the file:
./library/MyVendor/MyComponent/MyClass.php
You can then reference a class of the form MyVendor\MyComponent\MyClass simply with:
// At top of consuming file
use MyVendor\MyComponent\MyClass;
// In the consuming page/script/class.
$instance = new MyClass(); // instantiation
$val = MyClass::myStaticMethod(); // static method call
Determine the scope of usage
If I have functionality is required only for a particular class, then I keep that function as a method (or a collection of methods) in the class in which it is used.
If I have some functionality that will be consumed in multiple places in a single project, then I might break it out into a single class in my own library namespace, perhaps MyVendor.
If I think that a function/class will be consumed by multiple projects, then I break it out into its own project with its own repo (on Github, for example), make it accessible via Composer, optimally registering it with Packagist, and pay close attention to semantic versioning so that consumers of my package receive a stable and predictable product.
Copying folders from one project into another is do-able, of course, but it often runs into problems as you fix bugs, add functionality, and (sometimes) break backward-compatibility. That's why it is usually preferable to have those functions/classes in a separate, semantically-versioned project that serves as a single source-of-truth for that code.
Conclusion
Breaking functionality out into separate, namespaced classes that are autoloaded in a standard way gives plenty of "space" in which to develop custom functionality that is more easily consumed, more easily re-used, and more easily tested (a large topic for another time).

ELKI: Implementing a custom ResultHandler

I need to implement a custom ResultHandler but I am confused about how to actually integrate my custom class into the software package.
I have read this: http://elki.dbs.ifi.lmu.de/wiki/HowTo/InvokingELKIFromJava but my question is how are you meant to implement a custom result handler such that it shows up in the GUI?
The only way I can think of doing it is by extracting the elki.jar package and manually inserting my custom class into the source code, and then re-jarring the package. However I am fairly sure this is not the way it is meant to be done.
Also, in my resulthandler I need to output all the rows to a single text file with the cluster that each row belongs to displayed. How tips on how I can achieve this?
There are two questions in here.
in order to make your class instantiable by the UIs (both MiniGUI and command line), the classes must implement our Parameterization API. There are essentially two choices to make your class instantiable:
Add a public constructor without parameters (the UI won't know how to set your parameters!)
Add an inner static class Parameterizer that handles parameterization
in order to add your class to autocompletion (dropdown menu), the classes must be discovered by the MiniGUI/CLI/other UIs. ELKI uses two methods of discovery:
for .jar files, it reads the META-INF/elki/interfacename service files. This is a classic service-loader approach; except that we also allow ordering instances.
for directories only, ELKI will also scan for all .class files, and inspect them. This is mostly meant for development time, to avoid having to update the service files all the time. For performance reasons, we do not inspect the contents of .jar files; these are expected to use service files.
You do not need your class to be in the dropdown menu - you can always type the full class name. If this does not work, adding the name to the service file will not help either, but ELKI can either not find the class at all, or cannot instantiate it.
There is also a tutorial on implementing a custom result handler, but it does not discuss how to add it to the menu. In "development mode" - when having a folder with .class files - it will show up automatically.

How to build assetBundle without using Selection

I want to write my own editor that would allow me to search the whole Assets folder for object type of X and make an AssetBundle from them.
I went through all the manuals and docs and it seems that they all use the Selection class to build the Assets Bundle.
But what if there are 10 000+ objects scattered in different folders and I don't want to select each manually, yet I still want to track their dependencies. Is there a way to do so?
I have already tried editing Selection.objects, but as much as I understand it's limited to one concrete scene.
Is it possible to skip the whole Selection class and just use BuildPipeline.BuildAssetBundle() method? If yes, how to get the correct list of objects that can be used? Do I need to write my own deep threading loop to get the dependencies?
All you need is a list of objects. That's it. How you get them is irrelevant. You can do that with the Selection class, but if you have other means of finding the assets, that's no problem either.
As for dependencies, keep in mind that your final call will be something like:
BuildPipeline.BuildAssetBundle(main_asset, objects_array, path, BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets);
See that BuildAssetBundleOptions.CollectDependencies? It will make sure that all the necessary dependencies for the objects you've specified get included as well.

How to internationalize java source code?

EDIT: I completely re-wrote the question since it seems like I was not clear enough in my first two versions. Thanks for the suggestions so far.
I would like to internationalize the source code for a tutorial project (please notice, not the runtime application). Here is an example (in Java):
/** A comment */
public String doSomething() {
System.out.println("Something was done successfully");
}
in English , and then have the French version be something like:
/** Un commentaire */
public String faitQuelqueChose() {
System.out.println("Quelque chose a été fait avec succès.");
}
and so on. And then have something like a properties file somewhere to edit these translations with usual tools, such as:
com.foo.class.comment1=A comment
com.foo.class.method1=doSomething
com.foo.class.string1=Something was done successfully
and for other languages:
com.foo.class.comment1=Un commentaire
com.foo.class.method1=faitQuelqueChose
com.foo.class.string1=Quelque chose a été fait avec succès.
I am trying to find the easiest, most efficient and unobtrusive way to do this with the least amount of manual grunt work (other than obviously translating the actual text). Preferably working under Eclipse. For example, the original code would be written in English, then externalized (to properties, preferably leaving the original source untouched), translated (humanly) and then re-generated (as a separate source file / project).
Some trails I have found (other than what AlexS suggested):
AntLR, a language parser / generator. There seems to be a supporting Eclipse plugin
Using Eclipse's AST (Abstract Syntax Tree) and I guess building some kind of plugin.
I am just surprised there isn't a tool out there that does this already.
I'd use unique strings as methodnames (or anything you want to be replaced by localized versions.
public String m37hod_1() {
System.out.println(m355a6e_1);
}
then I'd define a propertyfile for each language like this:
m37hod_1=doSomething
m355a6e_1="Something was done successfully"
And then I'd write a small program parsing the sourcefiles and replacing the strings. So everything just outside eclipse.
Or I'd use the ant task Replace and propertyfiles as well, instead of a standalone translation program.
Something like that:
<replace
file="${src}/*.*"
value="defaultvalue"
propertyFile="${language}.properties">
<replacefilter
token="m37hod_1"
property="m37hod_1"/>
<replacefilter
token="m355a6e_1"
property="m355a6e_1"/>
</replace>
Using one of these methods you won't have to explain anything about localization in your tutorials (except you want to), but can concentrate on your real topic.
What you want is a massive code change engine.
ANTLR won't do the trick; ASTs are necessary but not sufficient. See my essay on Life After Parsing. Eclipse's "AST" may be better, if the Eclipse package provides some support for name and type resolution; otherwise you'll never be able to figure out how to replace each "doSomething" (might be overloaded or local), unless you are willing to replace them all identically (and you likely can't do that, because some symbols refer to Java library elements).
Our DMS Software Reengineering Toolkit could be used to accomplish your task. DMS can parse Java to ASTs (including comment capture), traverse the ASTs in arbitrary ways, analyze/change ASTs, and the export modified ASTs as valid source code (including the comments).
Basically you want to enumerate all comments, strings, and declarations of identifiers, export them to an external "database" to be mapped (manually? by Google Translate?) to an equivalent. In each case you want to note not only the item of interest, but its precise location (source file, line, even column) because items that are spelled identically in the original text may need different spellings in the modified text.
Enumeration of strings is pretty easy if you have the AST; simply crawl the tree and look for tree nodes containing string literals. (ANTLR and Eclipse can surely do this, too).
Enumeration of comments is also straightforward if the parser you have captures comments. DMS does. I'm not quite sure if ANTLR's Java grammar does, or the Eclipse AST engine; I suspect they are both capable.
Enumeration of declarations (classes, methods, fields, locals) is relatively straightforward; there's rather more cases to worry about (e.g., anonymous classes containing extensions to base classes). You can code a procedure to walk the AST and match the tree structures, but here's the place that DMS starts to make a difference: you can write surface-syntax patterns that look like the source code you want to match. For instance:
pattern local_for_loop_index(i: IDENTIFIER, t: type, e: expression, e2: expression, e3:expression): for_loop_header
= "for (\t \i = \e,\e2,\e3)"
will match declarations of local for loop variables, and return subtrees for the IDENTIFIER, the type, and the various expressions; you'd want to capture just the identifier (and its location, easily done by taking if from the source position information that DMS stamps on every tree node). You'd probably need 10-20 such patterns to cover the cases of all the different kinds of identifiers.
Capture step completed, something needs to translate all the captured entities to your target language. I'll leave that to you; what's left is to put the translated entities back.
The key to this is the precise source location. A line number isn't good enough in practice; you may have several translated entities in the same line, in the worst case, some with different scopes (imagine nested for loops for example). The replacement process for comments, strings and the declarations are straightforward; rescan the tree for nodes that match any of the identified locations, and replace the entity found there with its translation. (You can do this with DMS and ANTLR. I think Eclipse ADT requires you generate a "patch" but I guess that would work.).
The fun part comes in replacing the identifier uses. For this, you need to know two things:
for any use of an identifier, what is the declaration is uses; if you know this, you can replace it with the new name for the declaration; DMS provides full name and type resolution as well as a usage list, making this pretty easy, and
Do renamed identifiers shadow one another in scopes differently than the originals? This is harder to do in general. However, for the Java language, we have a "shadowing" check, so you can at least decide after renaming that you have an issues. (There's even a renaming procedure that can be used to resolve such shadowing conflicts
After patching the trees, you simply rewrite the patched tree back out as a source file using DMS's built-in prettyprinter. I think Eclipse AST can write out its tree plus patches. I'm not sure ANTLR provides any facilities for regenerating source code from ASTs, although somebody may have coded one for the Java grammar. This is harder to do than it sounds, because of all the picky detail. YMMV.
Given your goal, I'm a little surprised that you don't want a sourcefile "foo.java" containing "class foo { ... }" to get renamed to .java. This would require not only writing the transformed tree to the translated file name (pretty easy) but perhaps even reconstructing the directory tree (DMS provides facilities for doing directory construction and file copies, too).
If you want to do this for many languages, you'd need to run the process once per language. If you wanted to do this just for strings (the classic internationalization case), you'd replace each string (that needs changing, not all of them do) by a call on a resource access with a unique resource id; a runtime table would hold the various strings.
One approach would be to finish the code in one language, then translate to others.
You could use Eclipse to help you.
Copy the finished code to language-specific projects.
Then:
Identifiers: In the Outline view (Window>Show View>Outline), select each item and Refactor>Rename (Alt+Shift+R). This takes care of renaming the identifier wherever it's used.
Comments: Use Search>File to find all instances of "/*" or "//". Click on each and modify.
Strings:
Use Source>Externalize strings to find all of the literal strings.
Search>File for "Messages.getString()".
Click on each result and modify.
On each file, ''Edit>Find/Replace'', replacing "//\$NON-NLS-.*\$" with empty string.
for the printed/logged string, java possess some internatization functionnalities, aka ResourceBundle. There is a tutorial about this on oracle site
Eclipse also possess a funtionnality for this ("Externalize String", as i recall).
for the function name, i don't think there anything out, since this will require you to maintain the code source on many version...
regards
Use .properties file, like:
Locale locale = new Locale(language, country);
ResourceBundle captions= ResourceBundle.getBundle("Messages",locale);
This way, Java picks the Messages.properties file according to the current local (which is acquired from the operating system or Java locale settings)
The file should be on the classpath, called Messages.properties (the default one), or Messages_de.properties for German, etc.
See this for a complete tutorial:
http://docs.oracle.com/javase/tutorial/i18n/intro/steps.html
As far as the source code goes, I'd strongly recommend staying with English. Method names like getUnternehmen() are worse to the average developer then plain English ones.
If you need to familiarize foreign developers to your code, write a proper developer documentation in their language.
If you'd like to have Javadoc in both English and other languages, see this SO thread.
You could write your code using freemarker templates (or another templating language such as velocity).
doSomething.tml
/** ${lang['doSomething.comment']} */
public String ${lang['doSomething.methodName']}() {
System.out.println("${lang['doSomething.message']}");
}
lang_en.prop
doSomething.comment=A comment
doSomething.methodName=doSomething
doSomething.message=Something was done successfully
And then merge the template with each language prop file during your build (using Ant / Gradle / Maven etc.)

Xcode - exclude files in a custom configuration - better way?

I'm trying to come up with a way to make it easy to switch out our "mock" data services and our live ones. Basically, we'll have live servers with real web services, but for whatever reason, a developer may want to load data from static files (file urls).
I figured I would solve this problem by creating categories that override the methods that fetch the data, thus leaving original code untouched (it has no concept of the "mock" data). I don't want to litter my code with #ifdef.
I can put an #ifdef at the very beginning of each file that has categories in it, and I can set a custom flag in the configuration settings, but I'd rather just have a way to include or exclude the files depending on the configuration. Is that possible? How do you solve this problem?
See http://lists.apple.com/archives/xcode-users/2009/Jun/msg00153.html
The trick is to define EXCLUDED_SOURCE_FILE_NAMES in the configuration you want to exclude the files from, and set the value of that custom build setting to a list of the file names (or a pattern that matches those, and only those, file names).
I would recommend creating two targets one of which has the mock categories included and another one which does not.
When you want to test, just build the target containing the mock categories. Everything else can remain identical.
If you would like to add a file but do not wont to compile it. Go to (for all your targets) project>build phases>compile source and take out the file that you do not want to compile.