Java and JavaScript in the Database

Hello, I am trying to execute Java procedure in Oracle JVM. This procedure sends an SNMP request to the printer to find out its name; it uses the SNMP4j library

import java.io.IOException;
import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.Target;
import org.snmp4j.TransportMapping;
import org.snmp4j.event.ResponseEvent;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.Address;
import org.snmp4j.smi.GenericAddress;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.VariableBinding;
import org.snmp4j.transport.DefaultUdpTransportMapping;
public class Get_ink_levels_devices {
Snmp snmp = null;
String address = null;
/**
* Constructor
* @param add
*/
public Get_ink_levels_devices(String add)
{
address = add;
}
public static void main(String[] args) throws IOException {
/**
* Port 161 is used for Read and Other operations
* Port 162 is used for the trap generation
*/
Get_ink_levels_devices client = new Get_ink_levels_devices("udp:192.168.115.77/161");
client.start();
/**
* OID - .1.3.6.1.2.1.1.1.0 => SysDec
* OID - .1.3.6.1.2.1.1.5.0 => SysName
*.1.3.6.1.2.1.1.1.0
*.1.3.6.1.2.1.25.3.2.1.3.1
* => MIB explorer will be usefull here, as discussed in previous article
*/
String sysDescr = client.getAsString(new OID("1.3.6.1.2.1.25.3.2.1.3.1"));
System.out.println(sysDescr);
}
private void start() throws IOException {
TransportMapping transport = new DefaultUdpTransportMapping();
snmp = new Snmp(transport);
// Do not forget this line!
transport.listen();
}
/**
* Method which takes a single OID and returns the response from the agent as a String.
* @param oid
* @return
* @throws IOException
*/
public String getAsString(OID oid) throws IOException {
    ResponseEvent event = get(new OID[]{oid});
    if(event.getResponse() != null){
        return event.getResponse().get(0).getVariable().toString();
    } else {
        return "no target";
    }
}
/**
* This method is capable of handling multiple OIDs
* @param oids
* @return
* @throws IOException
*/
public ResponseEvent get(OID oids[]) throws IOException {
PDU pdu = new PDU();
for (OID oid : oids) {
pdu.add(new VariableBinding(oid));
}
pdu.setType(PDU.GET);
ResponseEvent event = snmp.send(pdu, getTarget(), null);
if(event != null) {
return event;
}
throw new RuntimeException("GET timed out");
}
/**
* This method returns a Target, which contains information about
* where the data should be fetched and how.
* @return
*/
private Target getTarget() {
Address targetAddress = GenericAddress.parse(address);
CommunityTarget target = new CommunityTarget();
target.setCommunity(new OctetString("public"));
target.setAddress(targetAddress);
target.setRetries(2);
target.setTimeout(5000);
target.setVersion(SnmpConstants.version1);
return target;
}
}

Hello, I am trying to execute Java procedure in Oracle JVM. This procedure sends an SNMP request to the printer to find out its name; it uses the SNMP4j library. I use Oracle 19c, I compiled this procedure using javac --release 8, after I loaded the snmp4j-2.8.3.jar library into the database using loadjava and then I loaded the procedure itself. Then I created a procedure in sqlplus CREATE OR REPLACE Procedure Test_ink AS LANGUAGE JAVA NAME 'Get_ink_levels_devices.main (java.lang.String [])'; and set exec permissions dbms_java.grant_permission (grantee => 'ADMIN', permission_type => 'SYS: java.net.SocketPermission', permission_name => '192.168.115.77:161',permission_action =>' accept, connect, listen, resolve ');

and granted GRANT JAVASYSPRIV TO Admin rights;

GRANT JAVAUSERPRIV TO Admin;

GRANT JAVAIDPRIV TO Admin;

I run the procedure this way:

set serveroutput on;

call dbms_java.set_output (1000000);

exec Test_ink;

But it does not return the name of the printer, but returns "no traget", although if I run the program in the console it returns the name. I don’t understand what I’m doing wrong. I didn’t specify the necessary permissions for Java or is there a problem in something else?