TCommunicationException HTTP error -1 null

I have a java programm that creates or updates a doctype named “molPropRelation” with
data from memory and a doctype named “molPropInit”.

The function “sv_molPrRel()” checks, if the data already exist in “molPropRelation”.

query=“molPropRelation[name=”"+so_nam+"" and ./property/name=""+prop_nam+""]";

tObjIt2=check_query(tObjAcc,query,xi);
.
.
.
if not found, then insert
if found, then update

after about 1000 updates/inserts with success the following error occures
in check_query():

check_query/TException: NestedException:HTTP error -1 null
Nested Exception (com.softwareag.tamino.db.api.invocation.TCommunicationException)

stacktrace:

com.softwareag.tamino.db.api.invocation.TCommunicationException HTTP error -1 null
at com.softwareag.tamino.db.api.invocation.http.THTTPInvocation.getInputStream(THTTPInvocation.java:286)
at com.softwareag.tamino.db.api.invocation.http.THTTPInvocation.doInvoke(THTTPInvocation.java:149)
at com.softwareag.tamino.db.api.invocation.TAbstractInvocation.doTemplateInvoke(TAbstractInvocation.java:282)
at com.softwareag.tamino.db.api.invocation.TAbstractInvocation.invoke(TAbstractInvocation.java:156)
at com.softwareag.tamino.db.api.invocation.TAbstractInvocation.invoke(TAbstractInvocation.java:135)
at com.softwareag.tamino.db.api.accessor.TStreamAccessorImpl.query(TStreamAccessorImpl.java:290)
at com.softwareag.tamino.db.api.accessor.TXMLObjectAccessorImpl.query(TXMLObjectAccessorImpl.java:228)
at package20.Tamino_access.check_query(Tamino_access.java:2283)
at package20.Tamino_access.sv_molPrRel(Tamino_access.java:442)
at package20.Cr_molPrRel.cr_molPropRelation(Cr_molPrRel.java:716)
at package20.Threat1.run(Threat1.java:334)


can anyone help ?


/****/

static TXMLObjectIterator check_query(TXMLObjectAccessor tObjAcc,
String query,xml_info xi) {
TQuery tQuery=null;
TResponse tResp=null;
TXMLObjectIterator tObjIt=null;

try {
tQuery=TQuery.newInstance(query);
tResp=tObjAcc.query(tQuery);
}
catch (com.softwareag.tamino.db.api.accessor.TQueryException e2){
pr_err(xi,“check_query”,query,e2);
tResp=null;
}

if (tResp!=null) tObjIt=tResp.getXMLObjectIterator();

return(tObjIt);
}


/
/

public static void pr_err(xml_info xi,String modname,String txt,
com.softwareag.tamino.db.api.common.TException e2) {
boolean ok=true;
String s;

if (modname!=null)
System.out.println(modname+"/TException: "+e2.getMessage());
else
System.out.println("TException: "+e2.getMessage());
if (txt!=null) System.out.println(“txt: “+txt);
e2.printStackTrace();
if (xi!=null && !xi.tconn.usesAutoCommitMode()) {
try {
xi.tconn.useAutoCommitMode();
}
catch (com.softwareag.tamino.db.api.connection.TTransactionModeChangeException e){
pr_err(xi,modname,txt,e);
ok=false;
}
if (ok) System.out.println(modname+”/AutoCommitMode gesetzt”);
}

return;
}

You could try it with the JDK1.4, it might be help.