It’s a dynamically-sized list of objects of the same type stored contiguously in memory.
dynamically-sized: The size of it can change as needed.
list: It stores multiple things together.
object: A bit of programmer defined data.
of the same type: all the objects in the list are defined the same way
stored contigiously in memory: if you think of memory as a bookshelf then all the objects on the list would be stored right next to each other on the bookshelf rather than spread across the bookshelf.
Dynamically sized but stored contiguously makes the systems performance engineer in me weep. If the lists get big, the kernel is going to do so much churn.
matlab likes to pick the smallest available spot in memory to store a list, so for loops that increase the size of a matrix it’s recommended to preallocate the space using a matrix full of zeros!
No. ArrayList is thread safe and implements the collections API. Vector doesn’t. Though if you’re using Java, there’s almost no instance where you would want to use a Vector instead of ArrayList.
It’s a dynamically-sized list of objects of the same type stored contiguously in memory.
It’s like a fancy list.
So is a wedding gift registry.
dynamically-sized: The size of it can change as needed.
list: It stores multiple things together.
object: A bit of programmer defined data.
of the same type: all the objects in the list are defined the same way
stored contigiously in memory: if you think of memory as a bookshelf then all the objects on the list would be stored right next to each other on the bookshelf rather than spread across the bookshelf.
Dynamically sized but stored contiguously makes the systems performance engineer in me weep. If the lists get big, the kernel is going to do so much churn.
Contiguous storage is very fast in terms of iteration though often offsetting the cost of allocation
Modern CPUs are also extremely efficient at dealing with contiguous data structures. Branch prediction and caching get to shine on them.
Avoiding memory access or helping CPU access it all upfront switches physical domain of computation.
matlab likes to pick the smallest available spot in memory to store a list, so for loops that increase the size of a matrix it’s recommended to preallocate the space using a matrix full of zeros!
Is that churn or chum? (RN or M)
Churm
Many things like each other lined up in a row, and you can take some away or put more in.
So an ArrayList?
No. ArrayList is thread safe and implements the collections API. Vector doesn’t. Though if you’re using Java, there’s almost no instance where you would want to use a Vector instead of ArrayList.