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copied!<p>You should use the Java annotation coupled with the javac annotation processor, as it's the most efficient solution. It's however a bit more complicated than the usual annotation paradigm.</p> <p><a href="http://docs.oracle.com/javase/8/docs/technotes/tools/windows/javac.html#sthref66" rel="nofollow">This link</a> shows you how you can implement an annotation processor that will be used at the compile time.</p> <p>If I reuse your example, I'd go this way:</p> <pre><code>@Target(ElementType.TYPE) @Retention(RetentionType.SOURCE) @interface MetaData { String table(); } abstract class Entity {} @MetaData(table="a") class A extends Entity {} @MetaData(table="b") class B extends Entity {} class EntityGetter { public <E extends Entity> E getEntity(Class<E> type) { MetaData metaData = type.getAnnotation(MetaData.class); if (metaData == null) { throw new Error("Should have been compiled with the preprocessor."); // Yes, do throw an Error. It's a compile-time error, not a simple exceptional condition. } String table = metaData.table(); // do whatever you need. } } </code></pre> <p>In your annotation processing, you then should check whether the annotation is set, whether the values are correct, and make the compilation fail.</p> <p>The complete documentation is available in the documentation for the <a href="http://docs.oracle.com/javase/8/docs/api/javax/annotation/processing/package-summary.html" rel="nofollow">package <code>javax.annotation.processing</code></a>.</p> <p>Also, a few tutorials are available on the Internet if you search for "java annotation processing".</p> <p>I will not go deeper in the subject as I never used the technology myself before.</p>

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