difference between array and arraylist

[ravi yandluri]

Hi All,

I confused abt array and arraylist difference.
pls send to me.

[Jeff Albertson]

Arrays: http://java.sun.com/docs/books/tutorial/java/data/arrays.html
ArrayList and other collections: http://java.sun.com/docs/books/tutorial/collections/index.html

[Adam Richards]

The bottom line is that an ArrayList can grow and shrink dynamically, at runtime. Arrays cannot. Once you define an array at compile time, it stays the same size forever. The tradeoff is that arrays can be faster, depending on what your code does.

[Tony Morris]

Originally posted by Adam Richards:
The bottom line is that an ArrayList can grow and shrink dynamically, at runtime. Arrays cannot. Once you define an array at compile time, it stays the same size forever. The tradeoff is that arrays can be faster, depending on what your code does.

To say that "structure A is faster/slower than structure B" is never true.
To say that "function F on structure A is faster/slower than structure B" may or may not be true.
To say that "function F on arrays is faster than ArrayList" is never true for all F.

This is a red herring.

[Layne Lund]

Another difference is that an array has "special" syntax to access its elements. For an ArrayList, use methods just like other objects.

Layne

[Ken Blair]

Furthermore, in 1.5 an ArrayList like any other Collection is generic and can be used with parameterized types. An array can't, at least not without unchecked casts. Plus, an ArrayList can be used anywhere a List or Collection is declared whereas an array cannot.

It's name is exactly what it is. A List implemented using an array.