What is the difference between arrayList and vector in java?

Answer 1

1)Synchronization: Vector is synchronized and arraylist are not. 2)Increment size: Vector can increment the size by double,arraylist can increment it by 50%.

2)The default size of vector has 10, arraylist have 0.

3)we can specify the increment size with the vector and with arraylist we can't.

4)Arraylist is very fast as it is non-synchronized.

Answer 2

A vector holds all data items in adjacent areas of memory, making transfer of the entire vector easy and insertion or deletion of items expensive when compared with lists. Lists hold items is disjoint areas of memory, making transfer of the entire list expensive but insertion and deletion of individual items relatively cheap. Classic vectors are also fixed in size, and limited to N items, while lists can dynamically grow and shrink. Vectors also offer indexed access to the element items. Lists don't. The classic vector's predecessor is an array. Modern implementations of vectors often aim at providing similar characteristic, but the underlying data structure may in fact be a list or a hash, and those vectors typically support dynamic re-sizing.

Answer 3

ArrayList

Think of this as a growable array. It gives you fast iteration and fast random access. To state the obvious: it is an ordered collection (by index), but not sorted. You might want to know that as of version 1.4, ArrayList now implements the new RandomAccess interface-a marker interface (meaning it has no methods) that says, "this list supports fast (generally constant time) random access." Choose this over a LinkedList when you need fast iteration but aren't as likely to be doing a lot of insertion and deletion.

Vector

Vector is a holdover from the earliest days of Java; Vector and Hashtable were the two original collections, the rest were added with Java 2 versions 1.2 and 1.4. A Vector is basically the same as an ArrayList, but Vector methods are synchronized for thread safety. You'll normally want to use ArrayList instead of Vector because the synchronized methods add a performance hit you might not need. And if you do need thread safety, there are utility methods in class Collections that can help. Vector is the only class other than ArrayList to implement RandomAccess.

Answer 4

Arrays and Vectors are both designed to hold multiple values in them but they have one basic difference.

The main difference between them is the fact that Arrays is a homogeneous data type where it can hold only objects of one data type whereas Vectors are heterogeneous. You can have objects of different data types inside a Vector.

Answer 5

ArrayList

Think of this as a growable array. It gives you fast iteration and fast random access. To state the obvious: it is an ordered collection (by index), but not sorted. You might want to know that as of version 1.4, ArrayList now implements the new RandomAccess interface-a marker interface (meaning it has no methods) that says, "this list supports fast (generally constant time) random access." Choose this over a LinkedList when you need fast iteration but aren't as likely to be doing a lot of insertion and deletion.

Vector

Vector is a holdover from the earliest days of Java; Vector and Hashtable were the two original collections, the rest were added with Java 2 versions 1.2 and 1.4. A Vector is basically the same as an ArrayList, but Vector methods are synchronized for thread safety. You'll normally want to use ArrayList instead of Vector because the synchronized methods add a performance hit you might not need. And if you do need thread safety, there are utility methods in class Collections that can help. Vector is the only class other than ArrayList to implement RandomAccess.

The only difference between the two is that Vectors are synchronized and hence threadsafe whereas ArrayLists are not. Otherwise they are both identical in terms of their features and usage.

Answer 6

In use they're almost identical. The only thing you, as the programmer, really need to know is that Vectors are thread-safe and ArrayLists are not.

Answer 7

An array has a fixed size, whereas the vector can grow in size as necessary.

Answer 8

Vectors are thread safe while ArrayLists are not

ArrayLists are faster than Vectors

These are 2 main differences between ArrayLists and Vectors.