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    <p>I believe you are making the same mistake I made when I was starting out: that the abstract class and the extending class are two piece welded together to form a single class with access to all of each others fields and methods etc.</p> <p>Sadly, this is not true: inheritance is a closer relationship that in a normal parent-child object, but access rules must still be obeyed e.g. if a method is declared <code>protected</code> in the abstract class and the extending class is in a different package, then it cannot be accessed (and vice versa).</p> <p>Because the method <code>showFields()</code> is defined in <code>AbstractTestClass</code>, it can only access the fields in that class. Fields in <code>TestClass</code> are essentially walled off.</p> <p>The only way around it that I can think of is to override <code>showFields()</code> in <code>TestClass</code>, swallow any exceptions about not being able to access private fields, then call <code>super.showFields()</code> and swallow any exceptions again. Not pretty.</p> <pre><code>public abstract class AbstractTest { private String abstractString = "abstract"; public void showFields() throws IllegalAccessException { for (Field field : this.getClass().getSuperclass().getDeclaredFields()) { try { System.out.println(field.get(this)); } catch (IllegalAccessException e) { // swallow } } } } public class MyTest extends AbstractTest { private String concreteString = "concreteString"; @Override public void showFields() throws IllegalAccessException { for (Field field : this.getClass().getDeclaredFields()) { try { System.out.println(field.get(this)); } catch (IllegalAccessException e) { // swallow } } super.showFields(); } } </code></pre> <p>I doubt this is what you had in mind...</p>
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    1. POaccessing child fields in abstract class throught reflection in java
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    1. USKidTempo
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    1. CO*disclaimer:* I've managed to avoid using reflection for many years now and I'm a happier many for it. I'm even finding myself using extending classes less and less, preferring to use interfaces and delegating methods instead - so please don't consider my answer to be authoritative in any way.
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    2. COA agree that reflection should be avoided, but try to experiment with self written annotations. So i must use them. Thanks for answer. I solved this problem changing visibility of fields to package. This package contains only abstract class and his children, so i think that won't be bad style.
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      1. USAnton Rudenko
    3. COYeah, a good package structure and thoughtful use of access levels is always a better idea than resorting to hackery.
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