Casting and generics, any performance difference?

Question

I have been coding in Android a lot lately, although I am comfortable in JAVA, but I lack some ideas about the basic concepts that are used there.

I am interested to know if there is a difference between the two codes.

First method:

//Specified as member variable.   
ArrayList <String> myList  = new ArrayList <String>(); 

and using String temp = myList.get(1);

Second method:

ArrayList myList  = new ArrayList(); //Specified as member variable.   

and using

String temp1 = myList.get(1).toString();   

I know him about casting. The first method has a big advantage over the second, Most of the time in real coding I have to use the second method, because the arraylist can take different types of data, I end up pointing

ArrayList <Object> = new ArrayList <Object>(); 

or more general way.

Answer 1

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Answer 2

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Answer 3

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Answer 4

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Answer 5

- " type erasure".

But if you use Java 1.5 or higher, you should use generics, not weakly typed copies.

Benefits of Generics -

* The flexibility of dynamic binding, with the advantage of static type-checking. Compiler-detected errors are less expensive to repair than those detected at runtime.
* There is less ambiguity between containers, so code reviews are simpler.
* Using fewer casts makes code cleaner.