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Thread: error in HashSet

  1. #1
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    Default error in HashSet

    Hi,

    I have a small program here where in im learning to use HashMap.
    import java.util.HashSet;
    import java.util.Set;
     
    public class test {
     
            public static void main(String[] args) {
                    Set set = new HashSet();
                    set.add("pooja");
                    if(set.contains("pooja")) {
                            System.out.println("contains"); }
                    else {
                            System.out.println("does not contain"); }
            }
    }
    But when i try to run this, it gives me an error saying
    "Note: test.java uses unchecked or unsafe operations.
    Note: Recompile with -Xlint:unchecked for details."

    Can anyone tell me what does this error mean ? and what do i do to make this program run ??

    Thank you in advance ..


  2. #2
    Administrator copeg's Avatar
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    Default Re: error in HashSet

    For what its worth its a warning and not an error. The collection you are using is not specified to hold any particular class...see Lesson: Generics (The Java™ Tutorials > Learning the Java Language)

    This thread has been cross posted here:

    http://www.java-forums.org/new-java/41834-error-hashset.html

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    Last edited by copeg; April 4th, 2011 at 09:23 AM.

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