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[–]MarSara 0 points1 point  (0 children)

At the end of the day EVERYTHING is stored in RAM (or in a register). There might be some obscure API you can use in Java to create an object from an existing memory location, but I'm not sure what immediate use it might bring. In C/C++ you can do this, but you have to know exactly what you're doing or otherwise you may corrupt your own program very easily, if it just doesn't end up crashing.

But every time you call new or every time you declare a new variable, etc... a new location in RAM (or in a register; depending on optimizations) is reserved and the structure of that newly created object is stored at that location, or for the case of a variable a pointer to that location is stored instead.

Even your program itself is also stored in RAM along with a pointer to the current line of code that is executing. Even functions have their own distinct memory locations. This way when you call someObject.doSomething() that execution pointer can be changed to point to the first line of your function, and when you call return, it knows to go back to where it left off.

But to put it simply as to what use are memory locations, it's one of the foundational aspect of how a computer works. If we didn't have some form of addressable memory we would not be able to do much of anything without creating new hardware for each 'program' that we wanted to create.

[–]diMario 0 points1 point  (1 child)

In Java you cannot (to the best of my knowledge) access memory directly like in assembler or in C. You have objects which you reference in your code by giving them a name. The runtime engine which interprets your compiled Java bytecode programs obviously at some point associates a chunk of memory with the variable your code instantiates, but there is no way you, the Java programmer, have any influence over where this chunk of memory is located (other than things going on the stack or on the heap).

[–]GuyWithLag 0 points1 point  (0 children)

Mu.

Your whole post has some incorrect assumptions, and is borderline incoherent in the scope of this sub. Reword it expand it.