I am attempting to enable my core java application for remote accessibility via JMX. However, two restrictions are making it harder than it should be.
a) I am not at the liberty to change the script which starts the app on the linux box. Therefore, I cannot pass any of the "jmxremote" parameters to the jvm.
b) It is very possible that the remote port ( com.sun.management.jmxremote.port = xxxx ) I specify is not open and I cannot modify the script to try another open port. I must do it automatically.
I tried to get around these restrictions by writing a class with would set all the required jmxremote params as well as find a "free" port.
public class JmxRemoteConnectionHelper{
@Override
public void init( ) throws Exception{
InetAddress address = InetAddress.getLocalHost();
String ipAddress = address.getHostAddress();
String hostname = address.getHostName();
String port = String.valueOf( getFreePort( ) );
System.setProperty("java.rmi.server.hostname", ipAddress );
System.setProperty("com.sun.management.jmxremote", "true" );
System.setProperty("com.sun.management.jmxremote.authenticate", "false" );
System.setProperty("com.sun.management.jmxremote.ssl", "false" );
System.setProperty("com.sun.management.jmxremote.port", port );
}
private final int getFreePort( ){
**//seedPort is passed in the constructor**
int freePort = seedPort;
ServerSocket sSocket = null;
for( int i=ZERO; i<PORT_SCAN_COUNTER; i++ ){
try{
freePort = freePort + i;
sSocket = new ServerSocket( freePort );
//FOUND a free port.
break;
}catch( Exception e ){
//Log
}finally{
if( sSocket != null ){
try{
sSocket.close();
sSocket = null;
}catch(Exception e ){
//Log
}
}
}
}
return freePort;
}
}
As shown below, I, then initialize it via spring.
<bean id="JmxRemoteConnection" class="JmxRemoteConnectionHelper" init-method="init" />
<bean id="mbeanServer" class="org.springframework.jmx.support.MBeanServerFactoryBean" depends-on="JmxRemoteConnection" />
<bean id="exporter" class="org.springframework.jmx.export.MBeanExporter" lazy-init="false" >
<property name="assembler" ref="assembler"/>
<property name="namingStrategy" ref="namingStrategy"/>
<property name="autodetect" value="true"/>
<property name="server" ref="mbeanServer"/>
</bean>
<bean id="jmxAttributeSource" class="org.springframework.jmx.export.annotation.AnnotationJmxAttributeSource"/>
<bean id="assembler" class="org.springframework.jmx.export.assembler.MetadataMBeanInfoAssembler">
<property name="attributeSource" ref="jmxAttributeSource"/>
</bean>
<bean id="namingStrategy" class="org.springframework.jmx.export.naming.MetadataNamingStrategy" lazy-init="true">
<property name="attributeSource" ref="jmxAttributeSource"/>
</bean>
To test, I start the app on my windows machine. It starts up correctly. However, when I bring up JConsole on the same box and try to connect via "remote process" (ip:port), I get a "connection refused" message at the bottom.
My suspicion is that the JMX agent is not seeing any of the remote system properties that I am setting.
I am using JDK 1.6.
Since you are already using Spring I think you should see if using a ConnectorServerFactoryBean can do what you are looking to do. I've never had to start a remote JMX server but it looks like that's what that object can do for you.