Jenk

/\[.*(?!<\])\]/mg

Kind of answers the question for you..

Use a RESTful protocol of your own design. Much quicker than the highly bloated SOAP protocol. Failing that, ditch the PHP code for Java, or vice versa.

Too vague a problem to fully assist, but you are calling a function on something that is not an object.

I would strongly reconsider your design implementation. You should not know what properties are within an object if they are not public.

static methods are not bound by inheritance. What you are doing is calling a method as if it were a function, i.e. not in a class at all. A class to a static method is nothing more than a namespace.

"Modular" just means that every class/object is concise and only encapsulates one type of behaviour, so that this maximises reusability. If you have an object that is too specific in the way it must be used, you'll be very restricted.

If you have a large application, with many different features, there is. Otherwise it can generally be considered superfluous to use both.

AJAX has absolutely nothing to do with this topic.

No, Dependency Injection is much, much more than Type Hinting.

Try reading it first.

Why not use DOM? php.net/dom

So what happens if you need to change your database class? Oops! You've got lots of finding/replacing to do! and on platforms that are stateful (i.e. not PHP) the registry is also much more usefull than a singleton, because it can be maintained within the session, and as it's nature is to maintain single instances of objects, it allows you to create instances unique to each session, but maintain the same "singleton" effect.

If only that were true.

Depends on your structure of session storage.