Generic method declaration

[Saibabaa Pragada]

Hi, How does the compile treat the following 2 generic methods ?

public class P624_GenericMethod01_TypeSafe_Ask {

//1. Please provide corresponding non-generic methods
    static <T> void show() { //2. What is the use of <T> ?
	  System.out.println("show()");
    }

    static <T> void getResult(T obj) { //3. What is the use of <T> ?
	  System.out.println("getResult");
    }

    public static void main(String[] args) {
	  P624_GenericMethod01_TypeSafe_Ask.show();
	  P624_GenericMethod01_TypeSafe_Ask.getResult("Hi");
    }
}    

[Deepak Bala]

The generic that is defined is never really used. What do you mean by 'how does the compiler treat it ?'

[Saibabaa Pragada]

How does the compiler/we can convert this generic style code methods in to non-generic style code methods ?
For example, Define class : class Animal<T> {}
Create Instance: Animal<Cat> ref = new Animal<Cat>();
The compile/we can treat/assume the class as class Animal<Cat>{} instead of class Animal<T> {}

Deepak Bala wrote:The generic that is defined is never really used. What do you mean by 'how does the compiler treat it ?'

[Deepak Bala]

Saibabaa Pragada wrote:How does the compiler/we can convert this generic style code methods in to non-generic style code methods ?
For example, Define class : class Animal<T> {}
Create Instance: Animal<Cat> ref = new Animal<Cat>();
The compile/we can treat/assume the class as class Animal<Cat>{} instead of class Animal<T> {}

Deepak Bala wrote:The generic that is defined is never really used. What do you mean by 'how does the compiler treat it ?'

How does a compiler treat the generic declaration 'T' internally ? I can guess but I am not sure how that spec is implemented.

[Mohamed Sanaulla]

Is Type Erasure what you were looking for?

[Saibabaa Pragada]

I am trying to understand how these 2 generic methods can be written as Non-generic methods.

mohammed sanaullah wrote:Is Type Erasure what you were looking for?

[Mohamed Sanaulla]

Saibabaa Pragada wrote:I am trying to understand how these 2 generic methods can be written as Non-generic methods.

mohammed sanaullah wrote:Is Type Erasure what you were looking for?

In the show() I dont see the Type T being used. Did you try passing some other data types for the method getResult?

[Saibabaa Pragada]

1. In the show() I dont see the Type T being used - Yes. It is not being used.
2. Did you try passing some other data types for the method getResult? --> Yes. I am giving code snippet again.
Did I provide what you are looking for ?

    public static void main(String[] args) {
	  P624_GenericMethod01_TypeSafe_Ask.show();
	  P624_GenericMethod01_TypeSafe_Ask.getResult("Hi");
    }    

[Mohamed Sanaulla]

Saibabaa Pragada wrote:
Did I provide what you are looking for ?

    public static void main(String[] args) {
	  P624_GenericMethod01_TypeSafe_Ask.show();
	  P624_GenericMethod01_TypeSafe_Ask.getResult("Hi");
    }    

int, double, String ...

[Saibabaa Pragada]

We cannot pass int, double, String as arguments because show() method doesn't take any parameters

[Mohamed Sanaulla]

Saibabaa Pragada wrote:We cannot pass int, double, String as arguments because show() method doesn't take any parameters

For the one which takes arguments.

[Saibabaa Pragada]

I don't understand whether you are asking or saying. Please provide full sentence with complete meaning.

[Mohamed Sanaulla]

Saibabaa Pragada wrote:I don't understand whether you are asking or saying. Please provide full sentence with complete meaning.

Sorry for that. What I meant was- With the generics in place- You can pass values of different data types to the method- getResult. I wanted you to try this in the code. After the String passing, you could add method calls to getResult which would pass an int or a double and so on.

[Saibabaa Pragada]

They all work fine because method has generic type. My question is whole different. Let me put it in this way.

1. static <T> void show() { // What is the use of <T> after static and before void?   
2.static <T> void getResult(T obj) { //What is the use of <T> after static and before void ?   

[Mohamed Sanaulla]

Saibabaa Pragada wrote:They all work fine because method has generic type. My question is whole different. Let me put it in this way.

1. static <T> void show() { // What is the use of <T> after static and before void?   
2.static <T> void getResult(T obj) { //What is the use of <T> after static and before void ?   

The <T> before the return type indicates that the Type T being used here is not related to the ones used in the class. A class can also have a generic declaration with Type T. Is this what you were looking for?
I remember someone reply to the similar in another post.

[Saibabaa Pragada]

I replied the answer for somebody's post. What I am thinking is,

1. static <T> void show() { // What is the use of <T> after static and before void? --> Doesn't make any sense to me..Not useful.
2. static <T> void getResult(T obj) { //What is the use of <T> after static and before void ? --> <T> should be defined to use T in the method parameter. If not Compiler error. <T> "T cannot be resolved to a type". I don't know the reason

Please advice if anybody has reasons for these 2 points.