How to extend IErrorParser in eclipse to define own syntax checking? - eclipse

My intention is to have own naming rules in eclipse editor for C programming
Ex: a function should start with File name, it shall contain maximum of 20 character- FILENAME_MaxOf20Char().
When it is violated has to show an warning.
To do this tried to extend org.eclipse.cdt.core.IErrorParser. But this one is parsing from compilor output.

IErrorParser is not the right extension point to use for this.
You want to use the Code Analysis (CodAn) framework and write a custom checker. See this page for documentation.

Related

scala / IntelliJ IDEA: how to add custom editor-level checks or replacement suggestions

When coding in scala in IntelliJ IDEA, sometimes will the IDE suggest to replace .size == 0 by .isEmpty. Some other times, when calling a printf, will the IDE check that the number of variadic arguments matches what's in the format and that they have the expected type...
Let's say I create a class/method, that could require editor-level replacement suggestions or argument checks, as you can with C# annotations make your classes do pretty prints in debugging sessions, could we add something (annotations?) so that the user of that class/method receives these replacement suggestions or has their arguments checked in their favorite editor (let's say IntelliJ IDEA, but that shouldn't be limited to that)?
Do custom annotations for custom editor-level suggestions or checks exist?

Can I use Eclipse templates to insert methods and also call them?

I'm doing some competitions on a website called topcoder.com where the objective is to solve algorithmic problems. I'm using Eclipse for this purpose, and I code in Java, it would be help me to have some predefined templates or macros that I can use for common coding tasks. For example I would like to write methods to be able to find the max value in and int[] array, or the longest sequence in an int[] array, and so on (there should be quite many of these). Note I can't write these methods as libraries because as part of the competition I need to submit everything in one file.
Therefore ideally, I would like to have some shortcut available to generate code both as a method and as a calling statement at once. Any ideas if this is possible?
Sure you can - I think that's a nifty way to auto-insert boilerplate or helper code. To the point of commenters, you probably want to group the code as a helper class, but the general idea sounds good to me:
You can see it listed in your available templates:
Then as you code your solution, you can Control+Space, type the first few characters of the name you gave your template, and you can preview it:
And then you can insert it. Be sure if you use a class structure to position it as an inner class:
Lastly - if you want to have a template inserts a call to method from a template, I think you would just use two templates. One like shown above (to print the helper code) and another that might look like this, which calls a util method and drops the cursor after it (or between the parentheses if you'd like, etc):
MyUtils.myUtilMethod1();${cursor}

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.)

how can I modify gvim to follow objects and variables to their definition?

I am used to using (ctrl+click) on Eclipse and following variables/objects to look at the definition in order to understand the code.
I just started my first job and I only have access to unix (vi or gvim). Is it possible to do what I'm looking for?
edit: What I mean by is it possible? Lets say class foo is defined in file foo.hpp and is instantiated in foo.cpp. I want to be able to reach the definition of class foo from any instantiation of it in foo.cpp
With Vim you can use tags files generated by exuberant-ctags and other compatible programs.
"Tags" are function and variables, their name, signature and kind are stored alongside their location in files that Vim is able to parse to allow you to navigate through your code.
:help tags will tell you all you need to know.

i18n in Symfony Forms

Is there any way I can use the format_number_choice function inside of a actions file. In fact I need to use it for a Form error message.
'max_size' => 'File is too large (maximum is %max_size% bytes).',
In English it's simply "bytes", but in other languages the syntax changes after a certain value (for example if the number is greater than 20 it's: "20 of bytes").
I can use parenthesis, of course, but if the framework offers support for doing this specific thing, why not to use it?!
The way it's currently implemented in the 1.4 branch, you can define only one translation per message using il18n XML files.
What you could do is create a custom validator which inherits the current validator (sfValidatorFile in your example) and does the size checking in the doClean method before calling its parent's method.
I suggest you take a look at the source to see how it works : sfValidatorFile
The correct way to handle number ranges for translation is explained here in the Definitive Guide. I won't reproduce it here as the documentation itself is clear and concise. Note however that the string is not extracted automatically by the i18n-extract task, so you need to add it manually - again, the documentation explains this.
So yes, you can use the format_number_choice() function inside an action - you just need to load the helper inside the action like this:
sfContext::getInstance()->getConfiguration()->loadHelpers('I18N');