CloneNotSupportedException should extends RuntimeException not Exception (original) (raw)

David Holmes david.holmes at oracle.com
Sun Oct 14 22:34:32 UTC 2012

Remi,

This ship has sailed you can't recall it. CloneNotSupportedException is a checked exception and needs to remain so for source and binary compatibility.

David

On 15/10/2012 2:19 AM, Remi Forax wrote:

Hi everybody, CloneNotSupportedException is thrown when a developer calls Object.clone() and forget to mark the current object as Cloneable. Because it's clearly a developer error, CloneNotSupportedException should be a subtype of RuntimeException and not of Exception.

I believe this change is backward compatible because RuntimeException is a subclass of Exception, so I propose to first change CloneNotSupportedException to extends RuntimeException. diff -r ff641c5b329b src/share/classes/java/lang/CloneNotSupportedException.java --- a/src/share/classes/java/lang/CloneNotSupportedException.java Sat Oct 13 10:15:57 2012 +0100 +++ b/src/share/classes/java/lang/CloneNotSupportedException.java Sun Oct 14 18:16:35 2012 +0200 @@ -42,7 +42,7 @@ */ public -class CloneNotSupportedException extends Exception { +class CloneNotSupportedException extends RuntimeException { private static final long serialVersionUID = 5195511250079656443L; /**

And then to clean up the whole JDK (in several patches) to remove all the unnecessary try/catch like the one in by example ArrayList.clone() public Object clone() { try { ArrayList v = (ArrayList) super.clone(); v.elementData = Arrays.copyOf(elementData, size); v.modCount = 0; return v; } catch (CloneNotSupportedException e) { // this shouldn't happen, since we are Cloneable throw new InternalError(e); } } will become public Object clone() { ArrayList v = (ArrayList) super.clone(); v.elementData = Arrays.copyOf(elementData, size); v.modCount = 0; return v; } cheers, Rémi

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