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POConfusing Java generics usage: how do I properly parameterize this?
 

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    <p>I'm looking at some code with this form:</p> <pre> <code> 1 package com.stackoverflow.java.questions; 2 import java.util.ArrayList; 3 import java.util.List; 4 public class B extends A&lt;B&gt; { 5 6 private 7 &lt;C extends A&gt; 8 List&lt;C&gt; getList(Class&lt;C&gt; cls) { 9 10 List&lt;C&gt; res = new ArrayList&lt;C&gt;(); // "snip"... some stuff happening in here, using cls 11 return res; 12 } 13 public 14 List&lt;A&gt; getList() { 15 return getList(A.class); 16 } 17 } 18 abstract class A&lt;C extends A&lt;C&gt;&gt; { 19 } </code> </pre> <p>Yes, I know it's ugly, but I reduced it as much as I could manage.</p> <p>My question is how do I properly parameterize the use of A on lines 7, 14, and 15?</p> <p>Currently, I get warnings (A is a raw type. References to generic type A should be parameterized) from Eclipse for lines 7 and 14. I suspect that I would get one for line 15 as well once I fix the other two, but I'm not certain. Either way, it's not currently parameterized and probably ought to be, but I have no idea what the syntax is supposed to be.</p> <p>Any thoughts on how to add the proper parameter semantics and syntax to get rid of these warnings?</p> <p>Note: I'm not sure if it matters whether or not A is a recursive generic. I still get the same warnings if I simply use "abstract class A {}" in place of its current definition.</p> <p>Honestly, if it were my own code I'd change it all to be a heck of a lot simpler. Unfortunately, it's part of an API so I'm trying to change it as little as possible.</p> <p>Thanks!</p> <p>UPDATE:</p> <p>I'm able to address the warnings by parameterizing them as one would expect, but at the cost of an error. It comes down to this, how do I get a Class&lt;A&lt;B&gt;&gt; from an abstract class?</p> <p>Something like,</p> <p>Class&lt;A&lt;B&gt;&gt; cls = A.class;</p> <p>However, this causes a type mismatch error.</p> <p>UPDATE, part 2:</p> <p>Turns out, ya just can't do it due to type erasure. See my other question <a href="https://stackoverflow.com/questions/2390662/java-how-do-i-get-a-class-literal-from-a-generic-type">here.</a></p>
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