data type in java

[kamalkant rajput]

hi,
I wanted to know is there any API in java by which I can know the type of data is coming e.g. whether it is Integer,String ,Boolean etc.
thanks in advance

[Ulf Dittmer]

What is "the data that is coming" - where is it coming from? In what format? Apparently not from inside of a JVM?

[kamalkant rajput]

thanks for reply,
My problem is like that suppose i am having a class from which i am getting an object but i don't what is data type of member variables.
I wanted to know the data type of member variables.

[Ulf Dittmer]

You mean the method returns a java.lang.Object? You can get at the class name through obj.getClass().getName() - that'll return the fully qualified class name.

You can also check for particular classes as follows:

Object obj = ...
 
if (obj instanceof Integer) {
   Integer i = (Integer) obj;
} else if (obj instanceof String) {
   String s = (String) obj;
} else if (obj instanceof MyMysteryClass) {
   MyMysteryClass m = (MyMysteryClass) obj;
}

[Bill Shirley]

A major point of Object-Oriented programming is that you DON'T know the types of the instance variables.

the Java introspection APIs could help you out, but you should probably be solving your problem in some other way,

if you want more detailed answers, provide an example of the problem you are having,