How List interface work ?

[Alvin chew]

hi, just wondering , how the List interface work ? i confuse as i know interface forced implemented class to write the method which declared in interface, my concern is

if we have following codes

 
 
List myArrayList = new ArrayList();
 
myArrayList.add("1");
   

as shown, how the "add" method from List interface work ? we didn't define the method..what is the hiding part behind ..

thank you very much for your time
[ July 26, 2004: Message edited by: Alvin chew ]

[Marilyn de Queiroz]

ArrayList implements List and overrides the add() method.

[Alvin chew]

Marilyn, you meant ArrayList already define "add" method ?

[Mani Ram]

Originally posted by Alvin chew:
Marilyn, you meant ArrayList already define "add" method ?

Correct. ArrayList is a concreate class which implements the List interface and overrides the add() method(s).

[Alvin chew]

thank you , mani ...i clear now ....is it possible we can have a look on the code for ArrayList class ?

[Jim Yingst]

Sure. Your JDK has a file called src.zip (or possibly src.jar) which contains the source code for most of the Java libraries. (Excluding native methods.) You can upen this with most any unzipping tool (including many file browsers, nowadays) or using

jar -xvf src.zip

[Alvin chew]

thanks , jim ...try it now ....

[Dirk Schreckmann]

Alvin, you might like a read of the "How my Dog learned Polymorphism" story in the JavaRanch Campfire Stories.

[Alvin chew]

thank dirk , reading