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copied!<p>There are essentially two ways to do this:</p> <p>You could continue down your current path and use reflection to construct the classes:</p> <pre><code>public void addIndividualsOfType(Class<? extends Individual> clazz){ for (ListIterator it = indiList.listIterator(); it.hasNext(); ){ it.next() it.add(clazz.newInstance()); // using no-args constructor } } </code></pre> <p>and to use a constructor with arguments you'd replace<code>it.add(clazz.newInstance())</code> with something like this:</p> <pre><code> Constructor<? extends Individual> cons = clazz.getConstructor( param1.getClass(), param2.getClass(), param3.getClass()); it.add(cons.newInstance(param1, param2, param3)); </code></pre> <p>(I've left out the exception handling ... but you get the picture.)</p> <p>However, an altogether better approach would be to refactor your code so that you passed in a factory object rather than a <code>Class</code> object. For example:</p> <pre><code>public interface IndividualFactory { public Individual create(T1 p1, T2 p2, T3 p3); } public static final IndividualFactory TALL_FACTORY = new IndividualFactory() { public Individual create(T1 p1, T2 p2, T3 p3) { return new TallIndividual(p1, p2, p3); } }; public void addIndividualsOfType(IndividualFactory factory){ for (ListIterator it = indiList.listIterator(); it.hasNext(); ){ it.next() it.add(factory.create(param1, param2, param3); } } </code></pre> <p>Note that the factory-based solution can be statically type-checked. By contrast, the reflective version has to deal with a number of type-related runtime exceptions.</p>

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