Java generic type for objects

Question

In Objective-C we have a generic type for objects called "id".

id someObject = someValue;
if([someObject isKindOfClass:[NSString class]]) {
    NSString *string = someObject;
}

I want to know if there's something like that in Java.

id someObject = someValue;
if(someObject instanceof String) {
    String string = someObject;
}

Answer 1

Unless I'm missing something, you were very close to the answer yourself:

// obtain your object from somewhere
Object someObject = obtainObjectInstance();

// if it's a string...
if(someObject instanceof String) {
    // cast and assign to some variable
    String string = (String)someObject;
}

As a side note, all object instances contain information about the object's class: someObject.getClass()