proxy-pattern

I am studying for the Spring Core certification and I am finding some doubts related to the proxying notion. So on the study material I find the following quiz: There is a Java configuration class that contains the following methods: @Bean public AccountRepository accountRepository(){ return new JdbcAccountRepository(); } @Bean public TransferService transferService1() { TransferServiceImpl service = new TransferServiceImpl(); service.setAccountRepository(accountRepository()); return service; } @Bean public TransferService transferService2() { return new TransferServiceImpl( new

Proxy pattern delegates the request to the Real subject after doing some additional processing like applying checks if request needs to be processed or not based on may be some credential checks. It has class diagram as below Proxy class has a direct reference to the concrete Subject. Decorator Pattern enriches the behavior of the component [like proxy it also does some additional processing and delegates the operation to the real component]. The class diagram of this pattern is similar to Proxy pattern with only difference being it has the reference to the interface of the component. Having

So, I was playing around with Proxy objects and while trying to see how they mix with spread syntax and de-structuring, I stubled upon this weird behavior: const obj = { origAttr: 'hi' } const handler = { get(target, prop) { console.log(prop); return 1; }, has(target, prop) { return true; }, ownKeys(target) { return [...Reflect.ownKeys(target), 'a', 'b']; }, getOwnPropertyDescriptor(target, key) { return { enumerable: true, configurable: true }; } } const test = new Proxy(obj, handler); const testSpread = { ...test}; console.log('Iterate test'); // Works OK, output as expected for (const i in

I'm trying to wrap a Python PyObject* in an Object class. In Python, everything is a PyObject* . A list is a PyObject* , and each item in the list is itself a PyObject* . Which could even be another list. etc. I'm trying to allow fooList[42] = barObj style syntax by means of a Proxy pattern ( here ). Now that I have that working, I want to extend it so that fooList[42] can be used as an Object . Specifically I want to be able to handle... fooList[42].myObjMethod() fooList[42].myObjMember = ... Object has a lot of methods, and currently fooList[42].myObjMethod() is going to first resolve

As I understood both Adapter and Proxy patterns make two distinct/different classes/objects compatible with each for communication. And both of them are Structural patterns. I am getting that both of them are pretty much similar with each other. Can some one explain what exactly make(s) them different? EDIT: I went through this question. But I'd rather like to have a close comparison between Adapter and Proxy. Ravindra babu Adapter: It allows two unrelated interfaces to work together through the different objects, possibly playing same role. It modifies original interface. UML diagram: You can

Can you give any good explanation what is the difference between Proxy and Decorator ? The main difference I see is that when we assume that Proxy uses composition and Decorator uses aggregation then it seems to be clear that by using multiple (one or more) Decorators you can modify/ add functionalities to pre-existing instance (decorate), whereas Proxy has own inner instance of proxied class and delegates to it adding some additional features (proxy behaviour). The question is - Does Proxy created with aggregation is still Proxy or rather Decorator ? Is it allowed (by definition in GoF

I was looking at the Proxy Pattern, and to me it seems an awful lot like the Decorator, Adapter, and Bridge patterns. Am I misunderstanding something? What's the difference? Why would I use the Proxy pattern versus the others? How have you used them in the past in real world projects? Proxy, Decorator, Adapter, and Bridge are all variations on "wrapping" a class. But their uses are different. Proxy could be used when you want to lazy-instantiate an object, or hide the fact that you're calling a remote service, or control access to the object. Decorator is also called "Smart Proxy." This is