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POannotation invisible?
 

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    <p>This puzzles me. I have a class with a custom annotation and I can't seem to verify that the annotation is present. What am I doing wrong here? If I run <code>MyOperationTest</code> (see below), I get this as a result:</p> <pre><code>implements Library.Operation: true has @Library.Marker: false Tada! </code></pre> <hr> <p>Library.java:</p> <pre><code>package com.example.gotchas; public class Library { private Library() {} public @interface Marker {} public interface Operation { public void execute(); } } </code></pre> <p>MyOperation.java:</p> <pre><code>package com.example.gotchas; @Library.Marker public class MyOperation implements Library.Operation { @Override public void execute() { System.out.println("Tada!"); } } </code></pre> <p>MyOperationTest.java:</p> <pre><code>package com.example.gotchas; public class MyOperationTest { static public void main(String[] args) { try { Class&lt;?&gt; cl = Class.forName("com.example.gotchas.MyOperation"); boolean implementsLibraryOperation = Library.Operation.class.isAssignableFrom(cl); boolean hasLibraryMarker = cl.isAnnotationPresent(Library.Marker.class); System.out.println("implements Library.Operation: " +implementsLibraryOperation); System.out.println("has @Library.Marker: "+hasLibraryMarker); if (implementsLibraryOperation) { Class&lt;? extends Library.Operation&gt; opClass = cl.asSubclass(Library.Operation.class); Library.Operation op = opClass.newInstance(); op.execute(); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (InstantiationException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } } } </code></pre>
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