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POHow do i solve this generic bug
 

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  1. POHow do i solve this generic bug
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    <p>i have the following code that won't compile because of generic problems. It comes from when i try to run the code. The problem is that i must fix the generic issue but i can't spot it whether i must change something in the class StAlgo or in the method.</p> <pre><code>public class StAlgo{ //signature selection sort public &lt;T extends Comparable&lt;T&gt;&gt; int selectionSort(T[] array) { } public static &lt;T extends Comparable&lt;T&gt;&gt; T[] getRandomPermutationOfIntegers(int size) { T[] data = (T[])new Comparable[size]; for (Integer i = 0; i &lt; size; i++) { data[i] = (T)i; } // shuffle the array for (int i = 0; i &lt; size; i++) { T temp; int swap = i + (int) ((size - i) * Math.random()); temp = data[i]; data[i] = data[swap]; data[swap] = temp; } return data; } public &lt;T extends Comparable&lt;T&gt;&gt; void trySelectionSort(){ int N = 100, M = 100; for(int i= 0; i &lt; N; i++){ T[] arrayInts = (T[])new Comparable[i]; for(int j= 0; j &lt; M; i++){ arrayInts = getRandomPermutationOfIntegers(i); //Collections.shuffle(Arrays.asList(arrayInts)); selectionSort(arrayInts); } } } } //Main class has the folling code: StAlgosa s = new StAlgosa(); s.trySelectionSort(); </code></pre> <p>I get the following error:</p> <pre><code>Exception in thread "main" java.lang.Error: Unresolved compilation problem: Bound mismatch: The generic method trySelectionSort() of type StAlgosa is not applicable for the arguments (). The inferred type Comparable&lt;Comparable&lt;T&gt;&gt; is not a valid substitute for the bounded parameter &lt;T extends Comparable&lt;T&gt;&gt; </code></pre> <p>how do i fix it?</p> <p>thanks</p>
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    1. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USEddy Freeman
    1. USEddy Freeman
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    1. PL
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      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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    2. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. COIt would be useful to give out the stack trace.
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      1. POHow do i solve this generic bug
      1. USPavan
    2. CONo, not really. The "unresolved compilation problem" exception means this class just didn't compile, but he told Eclipse to run the program anyway. The line numbers wouldn't be meaningful.
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      1. POHow do i solve this generic bug
      1. USErnest Friedman-Hill
 

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