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POInstantiate an object from a dynamically generated class
 

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    <p>I am currently trying to achieve something like this: Based on this class, I try to create a new instance of the class Class&lt;? extends AbstractValidator> returned by the method getValidator().</p> <pre><code>public abstract class AbstractEnumDefinition extends AbstractRequestFieldDefinition { private Vector&lt;String&gt; values = new Vector&lt;String&gt;(); public abstract void define(String lang); protected void addEnumDefinition(String value){ values.add(value); } public Vector&lt;String&gt; getValues(){ return values; } @Override public Class&lt;? extends AbstractValidator&gt; getValidator() { return new AbstractValidator() { @Override public boolean isValid(String value) { return values.contains(value); } @Override public String getDefaultValue() { return ""; } }.getClass(); } } </code></pre> <p>Say I create this class:</p> <pre><code>public class LanguageDefinition extends AbstractEnumDefinition { public LanguageDefinition() { super(); } @Override public void define(String language) { addEnumDefinition("BEL-fr"); addEnumDefinition("BEL-nl"); addEnumDefinition("BEL-en"); } } </code></pre> <p>Later in my code, I call</p> <pre><code>new LanguageDefinition().getValidator().getConstructor().newInstance() </code></pre> <p>The class I am trying to instantiate here is not declared anywhere, but "generated dynamically"/"dynamically created" within the AbstractEnumDefinition class.</p> <p>When trying to do this, I get an <code>java.lang.InstantiationException</code> for </p> <pre><code>be....servlets.model.extraction.filter.editor.AbstractEnumDefinition$1 </code></pre> <p>I guess this is due to the fact that this Class has to be explicitly created before hand, and not referenced dynamically?</p> <p>Is there some kind of solution that would allow me to not have to write one class per validator?</p> <p>Thanks for the help,</p> <p>Eric</p>
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    1. COWhat do you mean by *dynamically created class*? We're not sure if we understand you there.
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    2. COMay be absence of no-param constructor makes the getInstance() fail for this class. And that means that anonimous classes cannot be instantiated by reflection.
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    3. COJust updated the question, to clarify things. Thanks.
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