Skip to main content

Memory Usage in Java

Memory management in Java is not a thing to worry about, the Java Virtual Machine and the garbage collector handle it. However, when dealing with obfuscated codes, being aware of where things are stored in the memory is an advantage.


There are two logical places in the memory, the stack and the heap. Local variables, local reference variables and method invocations reside in the stack while instance variables, instance reference variables and objects reside in the heap.


Local variables as the name suggests are defined inside a method or as parameters of a method. Local reference variables on the other hand are those that refer to an object. These are defined inside a method or as parameters of a method. Method calls are pushed on to the stack.


Instance variables are primitive variables defined inside a class but outside of any method. Instance reference variables are those that refer to objects and are defined inside a class but outside of any method. Objects are representations of real-world entities that the program is trying to solve.

Labels:

Comments

Post a Comment

Popular posts from this blog

Architecture Complexity

Here are the items to consider: Coding to an interface Service Oriented Architecture Automated Testing Domain Driven Design Custom Data Access Layer Layered architecture Complexity is relatively equal the number of lines of code. Note that complexity is not bad. It must be justified.
Post a Comment
Read more

Moving on

So I bought my self a 2.5″ hard drive enclosure for about 750 bucks. I wish I have my own tools for constructing a device as such. Instead of going for a 2GB USB flash drive, I chose to salvage the 30GB hard drive of an incapacitated laptop. Cool isn’t it? Though relatively slower than a typical USB flash drive, the storage capacity outweighs it. [To God] Thanks for being there always.
Post a Comment
Read more

Bin to hex converter in 16-bit DOS assembly

Just a quick code like putting your keyboard where your brain is. There should be another way of doing this. I hate this code. start: xor al, al xor bl, bl xor cl, cl mov dl, 4 ; use dl as counter input: mov ah, 00 int 16h cmp ah, 1ch je exit cmp al, '0' jb input cmp al, '1' ja input convert: mov cl, dl dec cl ; dl - 1 sub al, 30h ; get original value shl al, cl ; place in the appropriate bit position or bl, al ; save in bl dec dl ; prepare for the next bit jnz input ; must be 4 bits cmp bl, 9 ja letter jbe number letter: add bl, 37h ; because 'A' - 37h is 0Ah jmp here number: add bl, 30h ; because '0' - 30h is 00h here: call display jmp start display: mov ah, 02h ...
Post a Comment
Read more