Hello!
There are some different approaches to fix this problem. We will be
discussing this within the JastAdd group next week. Hopefully we can
release a fix soon.
/Jesper
On 08/22/2012 05:16 PM, Jesper Mattsson wrote:
>
> Hi
>
> I have found a problem when using the beaver flag to JastAdd. The
> beaver.Symbol class has a final field /value/, that in the default
> constructor is set to /this/. When using copy() or fullCopy(), then
> the node is copied using clone(), and thus the /value/ field is set to
> a reference to the original node. This leads to strange memory leaks,
> where old nodes are retained because of this field.
>
> We have had huge problems in Eclipse with memory leaks, and changing
> ASTNode.clone() to set /value/ to /this/ solves those problems. Doing
> this requires using reflection (since /value/ is final). Here is one
> way to do that:
>
> *public*ASTNode<T> clone() *throws*CloneNotSupportedException {
>
> ASTNode node = (ASTNode)*super*.clone();
>
> node.in$Circle(*false*);
>
> node.is$Final(*false*);
>
> *try*{
>
> Field f = beaver.Symbol.*class*.getField("value");
>
> *new*ClearFinalFieldAction().perform(f, node);
>
> } *catch*(Exception e) {
>
> e.printStackTrace();
>
> }
>
> *return*node;
>
> }
>
> *private**static**class*ClearFinalFieldAction
> *implements*PrivilegedExceptionAction {
>
> *private*Field field;
>
> *public**void*perform(Field f, Object o) *throws*Exception {
>
> field= f;
>
> AccessController./doPrivileged/(*this*);
>
> f.set(o, o);
>
> }
>
> *public*Object run() *throws*Exception {
>
> field.setAccessible(*true*);
>
> *return**null*;
>
> }
>
> }
>
> Jesper
>
> *Jesper MATTSSON, MSc*
>
> Software Developer & IT Administrator
>
> Phone direct: +46 73 324 5909
>
> Email: jesper.mattsson_at_modelon.com <mailto:jesper.mattsson_at_modelon.com>
>
>
> Description: Description: Description: Modelon_2011_Gradient_RGB_400
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Received on Fri Sep 14 2012 - 11:15:59 CEST