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ArrayList sorting

Jeansonne Pierre
Greenhorn

Joined: Sep 11, 2011
Posts: 12


this code compiled succeed, but come out with warning message as below

Note: .\Sorting.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.


which part of code should i modify or improve to remove the warning messages?

Please help.
Thanks in advance
Winston Gutkowski
Bartender

Joined: Mar 17, 2011
Posts: 7892
    
  21

Jeansonne Pierre wrote:which part of code should i modify or improve to remove the warning messages?

Add a type to your Arraylist, viz:
ArrayList<Double> arrayList = new ArrayList<Double>();

Winston

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Jeansonne Pierre
Greenhorn

Joined: Sep 11, 2011
Posts: 12
Thanks Winston Gutkowski,

the warning messages gone and it succeed.

anyway, I'm wondering why it is

instead of ?

as the method argument received is in double primitive type.
Winston Gutkowski
Bartender

Joined: Mar 17, 2011
Posts: 7892
    
  21

Jeansonne Pierre wrote:anyway, I'm wondering why it is

as the method argument received is in double primitive type.

Because types must be objects. An ArrayList can't hold doubles.

Winston
 
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