0022233: Performance problems in Payment Monitor background process

diff --git a/modules/org.openbravo.advpaymentmngt/src/org/openbravo/advpaymentmngt/process/FIN_PaymentMonitorProcess.java b/modules/org.openbravo.advpaymentmngt/src/org/openbravo/advpaymentmngt/process/FIN_PaymentMonitorProcess.java
--- a/modules/org.openbravo.advpaymentmngt/src/org/openbravo/advpaymentmngt/process/FIN_PaymentMonitorProcess.java
+++ b/modules/org.openbravo.advpaymentmngt/src/org/openbravo/advpaymentmngt/process/FIN_PaymentMonitorProcess.java
@@ -27,6 +27,8 @@
 import java.util.HashMap;
 import java.util.List;
 
+import org.hibernate.ScrollMode;
+import org.hibernate.ScrollableResults;
 import org.hibernate.criterion.Projections;
 import org.hibernate.criterion.Restrictions;
 import org.openbravo.advpaymentmngt.utility.FIN_Utility;
@@ -92,9 +94,18 @@
         obc.setFilterOnReadableClients(false);
         obc.setFilterOnReadableOrganization(false);
       }
+      obc.setFetchSize(1000);
+      final ScrollableResults productScroller1 = obc.scroll(ScrollMode.FORWARD_ONLY);
+      int i = 0;
       final List<String> invoiceIds = new ArrayList<String>();
-      for (Invoice invoice : obc.list()) {
+      while (productScroller1.next()) {
+        final Invoice invoice = (Invoice) productScroller1.get()[0];
         invoiceIds.add(invoice.getId());
+        // clear the session every 100 records
+        if ((i % 100) == 0) {
+          OBDal.getInstance().getSession().clear();
+        }
+        i++;
       }
 
       for (String invoiceId : invoiceIds) {