Re: Preventing Memory Leak when using HashMap
Hi!
Sometimes if you need a mapping but don't want to bother cleaning it up
after the Mapped Object becomes obsolete the WeakHashMap might help you.
Though that depends greatly on use...
Christian
Am 11.02.2010 09:32, schrieb Krist:
Hi all,
Two classes below pass HashMap to each other, I want to avoid the
memory leak, other than using HashMap.remove(key), how to avoid memory
leak in my code below ?
FormInv class get return value from a lookup on class CashLookUp,
these are simplified code.
Thank you for your help,
Krist
public class FormInv extends PageController {
private HashMap CashInTable;
public void CashIn_returnAction(ReturnEvent returnEvent) {
String vCode = null ;
String vNo = null ;
if (returnEvent.getReturnValue()!=null){
this.CashInTable =(HashMap)returnEvent.getReturnValue();
vCode = (String)this.CashInTable.get("vDocCode");
vNo = (String)this.CashInTable.get("vDocNo");
// Is this the only way to avoid memory leak with this HashMap ?
// CashInTable.remove("vDocCode");
// CashInTable.remove("vDocNo");
}
}
}
public class CashLookUp {
private HashMap CashInTable;
public String selectButton_action() {
JUCtrlValueBindingRef
tabelCheck=(JUCtrlValueBindingRef)this.getCashInLov_Table().getRowData();
String docCode =
(String)tabelCheck.getRow().getAttribute("DocCode");
String docNo =
(String)tabelCheck.getRow().getAttribute("DocNo");
CashInTable= new HashMap();
CashInTable.put("vDocCode",docCode);
CashInTable.put("vDocNo",docNo);
AdfFacesContext.getCurrentInstance().returnFromDialog(CashInTable,null);
return null;
}
}
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