Which MBeans to use (and how) to programmatically determine memory lows for app (CQ5) deployed inside Weblogic - memory

Question

I have to write a standalone Java app that monitors CQ5, deployed inside Weblogic (especially memory usage).
I was able to connect to the Domain Runtime Server in weblogic, using the class below (as found in the docs).
Now, I want to know which MBeans I need to monitor memory lows, so I can fire an event whenever a certain threshold is being hit.
Can any of you give me some insight? This is a pure JMX / Java question, unrelated to CQ.
I am trying to programmatically recreate what Jconsole already does. But I need it programmatically because I need to talk to an external API in case certain thresholds are being hit.
public class PrintServerState {
private static MBeanServerConnection connection;
private static JMXConnector connector;
private static final ObjectName service;
private static final ObjectName bundleWrite;
static {
try {
service = new ObjectName("com.bea:Name=DomainRuntimeService,Type=weblogic.management.mbeanservers.domainruntime.DomainRuntimeServiceMBean");
} catch (MalformedObjectNameException e) {
throw new AssertionError(e.getMessage());
}
}
/*
* Initialize connection to the Domain Runtime MBean Server
*/
public static void initConnection(String hostname, String portString,
String username, String password) throws IOException,
MalformedURLException {
String protocol = "t3";
Integer portInteger = Integer.valueOf(portString);
int port = portInteger.intValue();
String jndiroot = "/jndi/";
String mserver = "weblogic.management.mbeanservers.domainruntime";
JMXServiceURL serviceURL = new JMXServiceURL(protocol, hostname,
port, jndiroot + mserver);
Hashtable h = new Hashtable();
h.put(Context.SECURITY_PRINCIPAL, username);
h.put(Context.SECURITY_CREDENTIALS, password);
h.put(JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES,
"weblogic.management.remote");
connector = JMXConnectorFactory.connect(serviceURL, h);
connection = connector.getMBeanServerConnection();
System.out.println("***************** get mbean count ************************* " + connection.getMBeanCount());
Set<ObjectName> mbeans = connection.queryNames(null, null);
for (ObjectName mbeanName : mbeans) {
System.out.println(mbeanName);
}
System.out.println("********************** ---- ***********************");
}
/*
* Print an array of ServerRuntimeMBeans.
* This MBean is the root of the runtime MBean hierarchy, and
* each server in the domain hosts its own instance.
*/
public static ObjectName[] getServerRuntimes() throws Exception {
return (ObjectName[])connection.getAttribute(service,
"ServerRuntimes");
}
/*
* Iterate through ServerRuntimeMBeans and get the name and state
*/
public void printNameAndState() throws Exception {
ObjectName[] serverRT = getServerRuntimes();
System.out.println("got server runtimes");
int length = (int) serverRT.length;
for (int i = 0; i < length; i++) {
String name = (String) connection.getAttribute(serverRT[i],
"Name");
String state = (String) connection.getAttribute(serverRT[i],
"Type");
System.out.println("Server name: " + name + ". Server state: "
+ state);
}
}
public static void main(String[] args) throws Exception {
String hostname = args[0];
String portString = args[1];
String username = args[2];
String password = args[3];
PrintServerState s = new PrintServerState();
System.out.println("hostname " + hostname);
System.out.println("portString " + portString);
System.out.println("username " + username);
System.out.println("password " + password);
initConnection(hostname, portString, username, password);
System.out.println("**************************************************");
s.printNameAndState();
connector.close();
}
}

Answer 1

Would this help -
domainRuntime()
cd('/ServerRuntimes/' + eval('managedServerName') + '/JVMRuntime/' + eval('managedServerName'))
heapFreeCurrentPerOld = str(cmo.getHeapFreePercent())
heapFreeCurrentValOld = str(cmo.getHeapFreeCurrent())