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    <p>You can try to use reflection:</p> <pre><code>public abstract class AClonable implements Cloneable{ private String val; public AClonable(){ } public AClonable(String s){ val=s; } public String toString(){ return val; } @Override public AClonable clone(){ try { System.out.println(getClass().getCanonicalName()); AClonable b= getClass().getDeclaredConstructor(String.class).newInstance(val); return b; } catch (InstantiationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalAccessException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalArgumentException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SecurityException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (InvocationTargetException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (NoSuchMethodException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } </code></pre> <p>}</p> <p>in the clone() method you call getClass(). Because the ACloneble ist abstract, there call will allways go to the concrete class.</p> <pre><code> public class ClonebaleOne extends AClonable{ public ClonebaleOne(){ super(); } public ClonebaleOne(String s) { super(s); // TODO Auto-generated constructor stub } </code></pre> <p>}</p> <p>and </p> <pre><code> public class ClonebaleTwo extends AClonable{ public ClonebaleTwo(){ super(); } public ClonebaleTwo(String s) { super(s); // TODO Auto-generated constructor stub } </code></pre> <p>}</p> <p>and finally</p> <pre><code> public static void main(String[] args){ AClonable one = new ClonebaleOne("One"); AClonable tow= new ClonebaleTwo("Two"); AClonable clone = one.clone(); System.out.println(clone.toString()); clone = tow.clone(); System.out.println(clone.toString()); } </code></pre> <p>Output:</p> <pre><code> ClonebaleOne One ClonebaleTwo Two </code></pre> <p>But it's more a hack than a solution</p> <p>[EDIT] my two clones were faster than ;)</p> <p>[EDIT] To be complete. Another implentation of clone() can be</p> <pre><code> @Override public AClonable clone(){ try { ByteArrayOutputStream outByte = new ByteArrayOutputStream(); ObjectOutputStream outObj = new ObjectOutputStream(outByte); ByteArrayInputStream inByte; ObjectInputStream inObject; outObj.writeObject(this); outObj.close(); byte[] buffer = outByte.toByteArray(); inByte = new ByteArrayInputStream(buffer); inObject = new ObjectInputStream(inByte); @SuppressWarnings("unchecked") Object deepcopy = inObject.readObject(); inObject.close(); return (AClonable) deepcopy; } catch (Exception e) { e.printStackTrace(); } return null; } </code></pre> <p>when your abstract class implements Serialazable. There you write your object to disc and create a copy with the value from the disc. </p>
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    1. USJan Piel
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    1. COI like your idea and maybe it will come in handy for me in the future, but I think I'm better off just defining clone for each subclass. Too bad there isn't a simpler way to achieve this.
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    2. COTo define them in each subclass is the best solution in the object orientated way. I agree there with sanbhat. I fear the Serialazable-solution is the slowest one and it is a hack, too.
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