问SNMP4J发送永不超时

EN

private ResponseEvent getSnmpResponse() {
    PDU pdu = createPdu();
    Target target = getTarget();
    try {
        ResponseEvent event = snmp.send(pdu, target, null);
        return event;
    }
    catch (IOException e ){
        System.out.println("Timed out");  
    }
}

protected PDU createPdu() {
    PDU pdu = new PDU();
    pdu.add(new VariableBinding(new OID(DISK_TOTAL_OID)));
    pdu.add(new VariableBinding(new OID(DISK_AVAIL_OID)));
    pdu.add(new VariableBinding(new OID(DISK_USED_OID)));
    pdu.add(new VariableBinding(new OID(DISK_PERCENT_USED_OID)));
    pdu.setType( PDU.GET );
    return pdu;
}

private Target getTarget() {
    CommunityTarget target = new CommunityTarget();
    target.setCommunity( new OctetString("public") );
    target.setAddress( GenericAddress.parse("dcadb2/161") );
    target.setRetries( 1 );
    target.setTimeout( 1000L );
    target.setVersion( SnmpConstants.version2c );
    return target;
}