Question

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.

Answer 1

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.