Why use proxy in Java?

Why use proxy in Java?

I have a question for you guys.

Is it really necessary to use the proxy class? I mean, if I have some object with its private methods/variables and I want to call this method from some another class, do I really need the proxy class in this case? Just curious why Java developers use proxy at all? I have a lot of code written by other developers, and most of them use the Proxy class, but I dont understand why? Could you give me some examples? Thank you! I'm going to give you an example. Let's say you have a class User which has a String name variable. And let's say you want to make sure that other users don't modify name of a user. For example if someone calls a method addUser(), let's say the addUser() function only operates on name variable. Now let's say there is a new user name X who wants to modify name of User class instance, he could do as follows: Class cls = User.class; User currentUser = (User)cls.newInstance(); currentUser.name = "X"; So if there are no proxies in the class, then we cannot prevent X from modifying a name value of User instance, since currentUser has no name field, and it could get modified. However if there is a Proxy class like this: User currentUser = (User)cls.newInstance(); Now X will not be able to modify name field, since name is private, he will get an exception when he tries to do so. This is a simple example, and the way it works with proxies is more advanced. However, it gives you an idea about the concept.

What is the difference between IP address and proxy server?

An IP address is the unique address assigned to each device on the internet, often via a subnet of 255 addresses. A proxy server is used to redirect requests to other servers in order to improve performance or to make the web site more accessible. A proxy server can take many forms and functions, but a typical example is a web browser that is configured to use a proxy server to access a different server than the one the web page is hosted on.