...

The

...

purpose

...

of

...

this

...

article

...

is

...

to

...

show

...

the

...

possibilities

...

of

...

server-side

...

monitoring

...

using

...

Geronimo,

...

a

...

Java

...

^TM 2

...

Platform

...

Enterprise

...

Edition

...

(J2EE)

...

application

...

server.

...

Monitoring

...

an

...

application

...

server

...

from

...

inside

...

saves

...

network

...

traffic,

...

since

...

monitored

...

information

...

can

...

be

...

analyzed,

...

filtered,

...

summarized,

...

and

...

set

...

into

...

an

...

application

...

specific

...

context

...

inside

...

the

...

server.

...

For

...

example

...

an

...

application

...

server

...

could

...

send

...

an

...

e-mail

...

when

...

the

...

response

...

time

...

of

...

our

...

online

...

shop

...

gets

...

unacceptable

...

big.

...

A

...

simple

...

web

...

application

...

has

...

been

...

used

...

to

...

develop

...

a

...

server-side

...

monitoring

...

component

...

that

...

monitors

...

three

...

servlets

...

and

...

gives

...

alarm

...

when

...

the

...

overall

...

average

...

processing

...

time

...

exceeds

...

a

...

certain

...

given

...

threshold.

...

What

...

is

...

needed

...

Anchor
What is needed
What is needed

JDK 5.0

...

(because

...

of

...

the

...

used

...

JConsole

...

tool;

...

it

...

is

...

not

...

included

...

in

...

JDK1.4):

...

http://java.sun.com/javase/downloads/index.jsp

...

Standard

...

Geronimo:

...

http://geronimo.apache.org/downloads.html

...

Sample

...

Code:

...

http://www.informatik.hs-furtwangen.de/~reich/Geronimo/GMontiorSample.zip

...

(Contents:

...

Sources,

...

shell

...

scripts,

...

archives,

...

README,

...

etc.)

...

Introduction

A lot of articles can be found in managing application servers with remote clients using the Java Management Extensions (JMX; http://java.sun.com/javase/technologies/core/mntr-mgmt/javamanagement/

...

).

...

These

...

management

...

client

...

applications

...

describe

...

how

...

to

...

connect

...

management

...

clients

...

to

...

a

...

server

...

and

...

how

...

to

...

retrieve

...

information

...

from

...

the

...

server

...

applications.

...

While

...

much

...

attention

...

has

...

been

...

given

...

to

...

the

...

client-side

...

aspects

...

of

...

JMX,

...

very

...

little

...

consideration

...

has

...

been

...

given

...

to

...

the

...

server-side

...

challenges

...

of

...

developing

...

and

...

deploying

...

management

...

beans

...

(MBeans).

...

The

...

reason

...

lays

...

in

...

the

...

difficulties

...

of

...

development

...

and

...

integration

...

of

...

such

...

components.

...

Often

...

it

...

is

...

not

...

possible

...

at

...

all.

...

With

...

the

...

appearance

...

of

...

Geronimo

...

the

...

server-side

...

monitoring

...

by

...

implementing

...

MBeans

...

for

...

monitoring

...

servlets

...

or

...

EJBs

...

is

...

simplified.

...

This

...

article

...

shows

...

how

...

to

...

monitor

...

the

...

application

...

server

...

Geronimo

...

from

...

inside

...

and

...

how

...

detailed

...

information

...

querying

...

the

...

MBeans

...

can

...

be

...

analyzed,

...

grouped

...

and

...

generated

...

to

...

Overview

...

about

...

MBeans

...

and

...

GBeans

...

This
...
section
...
gives
...
a
...
short
...
introduction
...
of
...
the
...
management
...
standard
...
JMX
...
(
...
http://java.sun.com/javase/technologies/core/mntr-mgmt/javamanagement/
...
)
...
with
...
its
...
fundamental
...
beans,
...
the
...
MBeans.
...
It
...
explains
...
that
...
Geronimo
...
can
...
be
...
extended
...
by
...
new
...
components,
...
if
...
they
...
are
...
GBeans.
...

Java

...

Management

...

Extension

...

Java
...
Management
...
eXtension
...
(JMX)
...
(
...
http://java.sun.com/javase/technologies/core/mntr-mgmt/javamanagement/
...
)
...
standardizes
...
the
...
managing
...
and
...
monitoring
...
of
...
applications
...
and
...
services.
...
It
...
enables
...
developers
...
to
...
write
...
management
...
programs
...
for
...
their
...
applications
...
in
...
a
...
vendor/neutral
...
fashion.
...
Another
...
important
...
standard
...
in
...
the
...
area
...
of
...
J2EE
...
is
...
JSR-77
...
(
...
http://jcp.org/en/jsr/detail?id=77
...
).
...
JSR-77
...
is
...
a
...
standard
...
model
...
for
...
managing
...
the
...
J2EE
...
platform
...
and
...
allows
...
application
...
server
...
vendors
...
to
...
present
...
performance
...
metrics
...
in
...
a
...
standard
...
way.
...
It
...
defines
...
a
...
set
...
of
...
standard
...
metric
...
types
...
that
...
can
...
be
...
used
...
to
...
monitor
...
J2EE
...
platforms.
...
The
...
following
...
types
...
of
...
metrics
...
are
...
defined
...
in
...
JSR-77:
...
range
...
statistics,
...
boundary
...
statistics,
...
bounded
...
range
...
statistics,
...
count
...
statistics,
...
and
...
time
...
statistics.
...
Fundamental
...
to
...
JMX
...
is
...
the
...
management
...
bean,
...
MBean.
...
There
...
are
...
four
...
types
...
of
...
MBeans
...
(Standard,
...
Dynamic,
...
Model,
...
Open),
...
and
...
each
...
provide
...
a
...
different
...
level
...
of
...
sophistication
...
for
...
management
...
and
...
monitoring
...
(see
...
http://java.sun.com/javase/technologies/core/mntr-mgmt/javamanagement/
...
for
...
more
...
details).
...
In
...
this
...
paper,
...
MBeans
...
are
...
used
...
for
...
the
...
monitoring
...
of
...
servlets
...
and
...
for
...
controlling
...
the
...
GBean
...
monitor
...
component.
...

Geronimo

...

hosting

...

our

...

Monitor

...

Component

...

Geronimo
...
is
...
in
...
the
...
first
...
place
...
a
...
Java
...
^TM 2
...
Platform
...
Enterprise
...
Edition
...
(J2EE)
...
application
...
server,
...
but
...
can
...
be
...
seen
...
as
...
a
...
general
...
service
...
container.
...
The
...
main
...
focus
...
of
...
developing
...
Geronimo
...
was
...
the
...
managing
...
and
...
scaling
...
of
...
application
...
servers.
...
Geronimo's
...
intention
...
was
...
never
...
to
...
re-implement
...
a
...
servlet
...
or
...
an
...
EJB
...
container,
...
but
...
to
...
use
...
existing
...
open
...
source
...
applications
...
(mainly
...
from
...
Apache
...
http://www.apache.org/
...
)
...
whenever
...
possible,
...
plug
...
it
...
together
...
and
...
build
...
a
...
new
...
application
...
server.
...
Anchor
...
Geronimo
...
extended
...
by
...
a
...
monitor
...
component
Geronimo extended by a monitor component

Image Added
The standard Geronimo distribution comes with Apache Tomcat http://tomcat.apache.org/
...
and
...
EJB
...
container
...
(OpenEJB
...
http://incubator.apache.org/openejb/
...
)
...
component.
...
Extending
...
Geronimo
...
by
...
a
...
monitoring
...
component,
...
developed
...
for
...
this
...
paper,
...
is
...
like
...
Tomcat,
...
or
...
any
...
other
...
component
...
as
...
long
...
as
...
they
...
are
...
GBeans,
...
as
...
shown
...
in
...
the
...
Figure:
...
#Geronimo
...
extended
...
by
...
a
...
monitor
...
component
...
.
...
The
...
fundamental
...
entity
...
within
...
Geronimo
...
are
...
Geronimo
...
Beans
...
(GBeans).
...

Geronimo

...

Beans

...

Anchor
Geronimo Beans
Geronimo Beans

Everything in Geronimo is basically a Geronimo Bean (GBean).

...

Geronimo's

...

kernel

...

handles

...

these

...

GBeans

...

and

...

stores

...

them

...

in

...

it

...

s

...

repository.

...

By

...

default

...

Geronimo

...

uses

...

not

...

a

...

database

...

but

...

a

...

file

...

The Server-Side Monitor Component

Subject of the section is a detailed architecture description of how the GBeans and MBeans are interacting. Discussed are the developed monitor classes and how to deploy the monitor component into Geronimo. Finally the monitor component is tested using the JConsole.

Geronimo Architecture Overview

First an overview about the integration of the monitor component into Geronimo's architecture is given in Figure #Geronimo architecture with integrated monitor component. It shows the JMX-Layer with the MBeanServer and the MBeans, the Tomcat component and the monitor component.

Anchor

	Geronimo architecture with integrated monitor component
	Geronimo architecture with integrated monitor component

Image Added
Geronimo registers each GBean as a MBean with the MBean Server, when the server is started. Tomcat http://tomcat.apache.org/

...

,

...

for

...

example,

...

consists

...

of

...

several

...

GBeans

...

and

...

therefore

...

consists

...

of

...

several

...

MBeans

...

(TomcatWebContainer,

...

TomcatWebConnector,

...

TomcatEngine,

...

TomcatJAASRealm,

...

etc.).

...

For

...

each

...

servlet

...

(S1,

...

S2,

...

S3)

...

in

...

Fig.

...

...

...

...

...

...

...

there

...

exists

...

a

...

MBean

...

(MB

...

_S1,

...

MB

...

_S2,

...

MB

...

_S3)

...

with

...

information

...

defined

...

in

...

the

...

JSR-77

...

specification.

...

The

...

dashed

...

line

...

objects

...

are

...

instantiated,

...

when

...

the

...

sample

...

monitor

...

component

...

(Servlet

...

Monitor

...

GBean)

...

is

...

deployed

...

into

...

Geronimo

...

using

...

the

...

"GBean

...

Builder".

...

The

...

MBeanServerKernelBridge

...

registers

...

each

...

loaded

...

GBean

...

as

...

a

...

MBean

...

(MB

...

_MC)

...

at

...

the

...

MBean

...

server.

...

The

...

instantiated

...

thread

...

(T

...

_C)

...

retrieves

...

information

...

from

...

the

...

servlet

...

MBeans

...

(MB

...

_S1,

...

MB

...

_S2,

...

MB

...

_S3).

...

Servlets

...

under

...

observation

...

It
...
is
...
not
...
the
...
content
...
of
...
this
...
article
...
to
...
show
...
how
...
to
...
develop
...
and
...
deploy
...
servlets.
...
There
...
is
...
a
...
simple
...
security
...
servlet
...
example
...
in
...
Geronimo's
...
user
...
guide
...
http://cwiki.apache.org/GMOxDOC11/apache-geronimo-v11-users-guide.html
...
,
...
if
...
you
...
want
...
to
...
know
...
more
...
about
...
web
...
application
...
in
...
Geronimo.
...
When
...
you
...
unpack
...
the
...
sources
...
(found
...
in
...
Section
...
#What
...
is
...
needed
...
)
...
and
...
follow
...
the
...
included
...
Readme
...
file
...
you
...
can
...
deploy
...
a
...
web
...
application
...
consisting
...
of
...
3
...
simple
...
servlets
...
(ServletStatistic,
...
ServeletData,
...
ServletSystemTime).
...
Now
...
you
...
should
...
be
...
able
...
to
...
call
...
the
...
servlets.
...
For
...
example:
...
http://localhost:8080/mysample/app1/ServletSystemTime
...
.
...

Server-Side

...

Monitor

...

Component

...

The
...
server-side
...
monitor
...
component
...
consists
...
of
...
2
...
classes
...
(see
...
Fig.
...
#Class
...
diagram
...
of
...
the
...
management
...
component
...
example
...
):
...
the
...
\verb+ServletMonitorGBean+,
...
which
...
implements
...
the
...
`GBeanLifecyle`
...
interface
...
and
...
the
...
\verb+AverageBuilder
...
+
...
thread,
...
which
...
is
...
doing
...
the
...
actual
...
collection
...
of
...
data
...
from
...
the
...
servlet
...
MBeans.
...
If
...
the
...
calculated
...
average
...
processing
...
time
...
is
...
above
...
the
...
threshold
...
an
...
alarm
...
is
...
generated.
...
The
...
alarming
...
function
...
is
...
not
...
sending
...
an
...
e-mail,
...
it
...
is
...
only
...
logging
...
"ALARM"
...
to
...
keep
...
the
...
code
...
simple.
Anchor
Class diagram of the management component example
Class diagram of the management component example

Image Added

The Monitor GBean

The Geronimo framework is injecting information about the MBean server reference and the MBean servlet object names into the constructor during deployment. Listing {#Listing 1] shows you how to inform the Geronimo kernel about the ability of the GBean. The GBeanInfoBuilder is used to tell Geronimo the name of the GBean class. Then the constructor injection is defined by addAttribute to specify the three servlet MBean names, addReference to specify the MBean server reference, and setConstructor to specify the constructor call.

Anchor

	Listing 1
	Listing 1

Code Block

title	ServletMonitorGBean.java (cutout)
borderStyle	solid



{anchor:Class diagram of the management component example}
!ClassDiagram.jpg!

h3. The Monitor GBean

The Geronimo framework is injecting information about the MBean server reference and the MBean servlet object names into the constructor during deployment. Listing {#Listing 1\] shows you how to inform the Geronimo kernel about the ability of the GBean. The {{GBeanInfoBuilder}} is used to tell Geronimo the name of the GBean class. Then the constructor injection is defined by {{addAttribute}} to specify the three servlet MBean names, {{addReference}} to specify the MBean server reference, and {{setConstructor}} to specify the constructor call.

{anchor:Listing 1}
{code:title=ServletMonitorGBean.java (cutout)|borderStyle=solid}
public static final GBeanInfo GBEAN_INFO;
static {
 GBeanInfoBuilder infoB = GBeanInfoBuilder.createStatic("ServletMonitorGBean", ServletMonitorGBean.class);
 infoB.addAttribute("servletName1", String.class, true);
 infoB.addAttribute("servletName2", String.class, true);
 infoB.addAttribute("servletName3", String.class, true);
 infoB.addReference("MBeanServerReference", MBeanServerReference.class);
 infoB.setConstructor(new String[] { "MBeanServerReference", "servletName1", "servletName2", "servletName3"});
{code}

Further

...

we

...

want

...

the

...

methods,

...

startCalcAverage

...

,

...

stopCalcAverage

...

,

...

defineThreshold

...

and

...

defineUpdateInterval

...

to

...

be

...

available

...

by

...

an

...

JMX

...

management

...

client.

...

This

...

allows

...

us

...

to

...

interact

...

with

...

the

...

monitor

...

component

...

through

...

a

...

MBean

...

using

...

the

...

JConsole

...

as

...

shown

...

in

...

Section

...

...

...

...

...

.

...

Publishing

...

GBean

...

methods

...

through

...

a

...

MBean

...

is

...

done

...

by

...

the

...

addOperation

...

of

...

the

...

GBeanInfoBuilder

...

by

...

specifying

...

the

...

method

...

names

...

and

...

parameters,

...

as

...

seen

...

in

...

Listing

...

#Listing

...

2

...

:

...

Anchor

...

	Listing 2
	Listing 2

2} {code:title= |=

Code Block

title

ServletMonitorGBean.java

(cutout)

borderStyle

	solid

}
infoB.addOperation("startCalcAverage");
 infoB.addOperation("stopCalcAverage");
 infoB.addOperation("defineThreshold",new Class[]{int.class});
 infoB.addOperation("defineUpdateInterval",new Class[]{int.class});
{code}

The

...

MBean

...

configuration

...

process

...

is

...

finished

...

by

...

setting

...

the

...

variable

...

GBEAN_INFO

...

.

...

Thus

...

the

...

MBeanServerKernelBridge

...

can

...

use

...

getGBeanInfo()

...

to

...

get

...

a

...

GBeanInfo

...

object

...

(Listing

...

#Listing

...

3

...

)

...

with

...

the

...

MBean

...

configuration

...

and

...

builds

...

the

...

appropriate

...

MBean

...

MB

...

_MC Figure:

...

...

...

...

...

...

...

.

Anchor

	Listing 3
	Listing 3

{anchor:Listing 3} {code:title= |=

Code Block

title

ServletMonitorGBean.java

(cutout)

borderStyle

	solid

}
GBEAN_INFO = infoB.getBeanInfo();
public static GBeanInfo getGBeanInfo() { return GBEAN_INFO; }
{code}

h3. The AverageBuilder Thread

The {{AverageBuilder}} class

The AverageBuilder Thread

The AverageBuilder class (Fig.

...

...

...

...

...

...

...

...

)

...

is

...

a

...

thread

...

which

...

is

...

querying

...

the

...

servlet

...

MBeans.

...

To

...

query

...

information

...

from

...

servlet

...

MBeans,

...

like

...

the

...

requestCounter

...

,

...

you

...

have

...

to

...

know

...

the

...

object

...

name

...

of

...

the

...

MBean.

...

You

...

can

...

find

...

out

...

about

...

the

...

object

...

name

...

using

...

a

...

JMX

...

management

...

client.

...

In

...

the

...

section,

...

...

...

...

...

...

,

...

it

...

is

...

shown

...

how

...

to

...

find

...

out

...

about

...

the

...

object

...

names

...

of

...

the

...

servlet

...

MBeans.

...

Since

...

we

...

injected

...

this

...

information

...

during

...

the

...

deployment

...

process

...

of

...

the

...

GBean,

...

we

...

are

...

not

...

to

...

worry

...

about

...

that

...

at

...

the

...

moment.

...

Having

...

the

...

MBean

...

object

...

name

...

we

...

get

...

the

...

information

...

precessingTime

...

and

...

requestCount

...

as

...

follows

...

(see

...

Listing

...

#Listing

...

4

...

):

Anchor

	Listing 4
	Listing 4

{anchor:Listing 4} {code:title= |=

Code Block

title

ServletMonitorGBean.java

(cutout)

borderStyle

	solid

}
ObjectName objNameStatisticServlet = ObjectName.getInstance(statisticServlet);
ObjectName objNameDataServlet=ObjectName.getInstance(dataServlet);
ObjectName objNameSystemTimeServlet = ObjectName.getInstance(systemTimeServlet);
long pt1=((Long)mbserver.getAttribute(objNameStatisticServlet, "processingTime")).longValue();
int rc1=((Integer)mbserver.getAttribute(objNameStatisticServlet, "requestCount")).intValue();
{code}

Doing

...

this

...

for

...

all

...

3

...

servlets

...

and

...

building

...

the

...

average

...

can

...

be

...

seen

...

in

...

the

...

source

...

code.

...

Deploying

...

the

...

Server-Side

...

Monitor

...

Component

...

When

...

the

...

GBean

...

monitor

...

component

...

is

...

compiled,

...

it

...

has

...

to

...

be

...

deployed

...

into

...

Geronimo.

...

For

...

deploying

...

the

...

monitor

...

component

...

everything

...

has

...

to

...

be

...

packaged

...

according

...

to

...

Geronimo

...

(see

...

Geronimo's

...

User

...

Guide

...

http://cwiki.apache.org/GMOxDOC11/apache-geronimo-v11-users-guide.html

...

).

...

That

...

means

...

you

...

have

...

to

...

pack

...

your

...

GBeans

...

with

...

a

...

deployment-plan

...

into

...

a

...

jar

...

file,

...

e.g.

...

SimpleServletMonitor-1.0.jar

...

and

...

deploy

...

it.

...

For

...

the

...

deployment,

...

we

...

have

...

chosen

...

the

...

java

...

deployment

...

program,

...

deployer:

{

Code Block
} java -jar $GERONIMOHOME/bin/deployer.jar --user system --password manager deploy SimpleServletMonitor-1.0.jar {code}

It

...

is

...

a

...

lot

...

faster

...

using

...

the

...

deployer

...

program,

...

then

...

doing

...

all

...

the

...

clicking

...

using

...

Geronimo's

...

browser

...

based

...

management

...

tool

...

(

...

http://localhost:8080/console

...

).

...

With

...

the

...

example

...

code,

...

there

...

comes

...

also

...

some

...

simple

...

Linux

...

shell

...

scripts

...

supporting

...

deployment,

...

un-deployment,

...

listing,

...

etc.

Anchor

	Deployment Plans for Geronimo's GBeans
	Deployment Plans for Geronimo's GBeans

Deployment Plans for Geronimo's

...

GBeans

...

Geronimo's

...

deployment

...

plans

...

(

...

geronimo-service.xml

...

)

...

state

...

information

...

about

...

GBean

...

names,

...

references

...

and

...

dependencies.

...

For

...

a

...

more

...

detailed

...

description

...

about

...

the

...

deployment

...

descriptor,

...

see

...

http://cwiki.apache.org/GMOxDOC11/apache-geronimo-v11-users-guide.html

...

.

...

Our

...

deployment

...

descriptor

...

(Listing

...

#Listing

...

5

...

)

...

consists

...

of

...

an

...

<environment>

...

and

...

and <gbean> part:

Anchor

	Listing 5
	Listing 5

{anchor:Listing 5} {code:title=|=

Code Block

title

geronimo-service.xml

borderStyle

	solid

}
<?xml version="1.0" encoding="UTF-8"?>
<module xmlns="http://geronimo.apache.org/xml/ns/deployment-1.1">
  <environment>...</environment>
  <gbean ...>...</gbean>
</module>
{code}

h4. The

The ``environment''

...

part:

...

We

...

have

...

to

...

give

...

our

...

monitor

...

GBean

...

an

...

unique

...

name

...

inside

...

Geronimo

...

by

...

defining

...

its

...

groupId

...

,

...

artifactId

...

,

...

version

...

and

...

type

...

.

...

Furthermore

...

we

...

have

...

to

...

define

...

<dependencies>

...

(see

...

Listing:

...

#Listing6

...

).

...

Because

...

we

...

want

...

to

...

inject

...

the

...

object

...

reference

...

for

...

MBeanServerReference

...

to

...

the

...

GBean

...

constructor

...

our

...

deployment

...

process

...

depends

...

on

...

the

...

geronimo/rmi-naming

...

defined

...

as

...

the

...

artifactId

...

in

...

the

...

geronimo-service.xml

...

.

...

The

...

serialized

...

version

...

of

...

that

...

reference

...

is

...

found

...

in

...

the

...

repository

...

under:

...

geronimo/rmi-naming

...

.

Anchor

	Listing 6
	Listing 6

{anchor:Listing 6} {code:title=|=

Code Block

title

geronimo-service.xml

borderStyle

	solid

}
<environment>
  <moduleId>
    <groupId>mysample</groupId>
    <artifactId>SimpleServletMonitor</artifactId>
    <version>1.0</version>
    <type>car</type>
  </moduleId>
  <dependencies>
    <dependency>
      <groupId>geronimo</groupId>
      <artifactId>rmi-naming</artifactId>
      <type>car</type>
    </dependency>
  </dependencies>
</environment>
{code}

h4. The

The ``gbean''

...

part:

...

First

...

you

...

have

...

to

...

define

...

the

...

name

...

of

...

the

...

GBean

...

and

...

the

...

exact

...

class

...

name

...

as

...

XML

...

attributes

...

of

...

the

...

element

...

<gbean>

...

(see

...

Listing:

...

#Listing7

...

).

...

Then

...

you

...

define

...

all

...

the

...

references

...

and

...

attributes,

...

which

...

should

...

be

...

injected

...

during

...

deployment.

Anchor

	Listing 7
	Listing 7

{anchor:Listing 7} {code:title=|=

Code Block

title

geronimo-service.xml

borderStyle

	solid

}
<gbean name="ServletMonitorGBean" class="de.hsfurtwangen.informatik.ServletMonitorGBean">
  <reference name="MBeanServerReference">
    <name>MBeanServerReference</name>
  </reference>
  <attribute name="servletName1" type="java.lang.String">
    Geronimo:j2eeType=Servlet,name=ServletStatistic,WebModule=//localhost/mysample,J2EEApplication=none,J2EEServer=none
  </attribute>
  <attribute name="servletName2" type="java.lang.String">
    Geronimo:j2eeType=Servlet,name=ServletData,WebModule=//localhost/mysample,J2EEApplication=none,J2EEServer=none
  </attribute>
  <attribute name="servletName3" type="java.lang.String">
    Geronimo:j2eeType=Servlet,name=ServletSystemTime,WebModule=//localhost/mysample,J2EEApplication=none,J2EEServer=none
  </attribute>
</gbean>
{code}

As

...

seen

...

in

...

our

...

example

...

above

...

(Listing:

...

#Listing7

...

),

...

the

...

following

...

parameters

...

are

...

injected

...

by

...

constructor

...

injection

...

of

...

the

...

Geronimo

...

framework:

...

MBeanServerReference:

...

The

...

corresponding

...

source

...

code

...

in

...

the

...

GBean

...

class

...

is:

...

GBeanInfoBuilder.addReference("MBeanServerReference",MBeanServerReference.class)

...

servleteName1:

...

The

...

corresponding

...

source

...

code

...

in

...

the

...

GBean

...

class

...

is:

...

GBeanInfoBuilder.addAttribute("servletName1",String.class)

...

servletName2:

...

The

...

corresponding

...

source

...

code

...

in

...

the

...

GBean

...

class

...

is:

...

GBeanInfoBuilder.addAttribute("servletName2",String.class)

...

servletName3:

...

The

...

corresponding

...

source

...

code

...

in

...

the

...

GBean

...

class

...

is:

...

GBeanInfoBuilder.addAttribute("servletName3",String.class)

...

Testing the Monitor Component

Accessing Geronimo using JConsole

We want to use JConsole http://java.sun.com/j2se/1.5.0/docs/guide/management/jconsole.html, http://java.sun.com/j2se/1.5.0/docs/tooldocs/share/jconsole.html, which is a JMX-compliant GUI tool that connects to a running JVM. If the JAVA_HOME environment variable is set to a JDK 5.0, you only have to type in:

Anchor

	JConsole
	JConsole

Image Added
To connect to your Geronimo server you have to use the following settings in your JConsole (see Fig. #JConsole):

JMX URL: service:jmx:rmi:///jndi/rmi://localhost:1099/JMXConnector
User Name: system
Password: manager

After the management client is connected to Geronimo you switch to the MBean view (see Fig. #Servlet MBean view) and navigate to one of the deployed servlets, e.g. ServletStatistic (1st and 2nd figure of Fig. #Servlet MBean view).

Anchor

	Servlet MBean view
	Servlet MBean view

Image Added

One interesting information is the object name (3rd figure of Fig. #Servlet MBean view)) that is used in the deployment descriptor for Geronimo's GBean deployment plan (see section #Deployment Plans for Geronimo's GBeans).

Anchor

	Interacting with the Monitor Component
	Interacting with the Monitor Component

Interacting with the Monitor Component: ServletMonitorGBean

First, navigate to the GBean (see Fig. #GBean Operations). Then you switch to the operations view. Now you have access to all the methods you defined in the GBean with \verb+GBeanInfoBuilder+. Let's start the process by calculating the average processing time of the 3 servlets. Just click on \verb+startCalcAverage()+ and you can see in the \verb+GERONIMO_HOME/var/log/geronimo.out+ file that the averages are calculated. Now reload the servlets several times, so that you can see changes in the output. You could also change the update time for the information polling of the servlets. Click first on \verb+parameter0+ and set the value to 5000 and then on \verb+defineUpdateInterval+. Now every 5s the data is collected from the servlets.
Play around and have fun.

Anchor

	GBean Operations
	GBean Operations

Image Added

Conclusion

An overview of the used technologies, Geronimo's GBeans and JMX has been given. You should now have an idea how to develop and deploy a monitor component inside Geronimo application server and how to improve the monitoring. The developed example shows a server's ability to do its own monitoring and application specific alarming. There are a lot more possibilities what can be done. For example a server could monitor the number of servlet requests and if there are more then, e.g. 20 per seconds, there might be a denial of service attack. Analyze the monitored data inside the server and optimize Geronimo's configuration, e.g. thread pool size. etc.

References

Sun's java management extensions (JMX) page. http://java.sun.com/javase/technologies/core/mntr-mgmt/javamanagement/

...

.

...

JConsole

...

reference.

...

http://java.sun.com/j2se/1.5.0/docs/tooldocs/share/jconsole.html

...

.

...

JConsole

...

manual.

...

http://java.sun.com/j2se/1.5.0/docs/guide/management/jconsole.html

...

.

...

JSR-77:

...

J2EE

...

management

...

specification.

...

http://jcp.org/en/jsr/detail?id=77

...

.

...

Apache

...

home

...

page.

...

http://www.apache.org/

...

.

...

Tomcat

...

home

...

page.

...

http://tomcat.apache.org/

...

.

...

OpenEJB

...

home

...

page.

...

http://incubator.apache.org/openejb/

...

.

...

Martin

...

Fowler;

...

Inversion

...

of

...

control

...

containers

...

and

...

the

...

dependency

...

injection

...

pattern.

...

;

...

http://www.martinfowler.com/articles/injection.html

...

;

...

January;

...

2004.

...

Niel

...

Frod;

...

Dependency

...

injection

...

in

...

apache

...

geronimo,

...

part

...

1:

...

A

...

new

...

way

...

to

...

look

...

at

...

decoupling

...

in

...

j2ee

...

applications.

...

;

...

http://www-128.ibm.com/developerworks/opensource/library/os-ag-ioc1/

...

;

...

February;

...

2006.

...

Niel

...

Frod;

...

Dependency

...

injection

...

in

...

apache

...

geronimo,

...

part

...

2:

...

The

...

next

...

generation.

...

;

...

http://www-128.ibm.com/developerworks/opensource/library/os-ag-ioc2/

...

;

...

February;

...

2006.

Child pages

Page History

Versions Compared

Old Version 15

New Version Current

Key

What

is

needed

AnchorWhat is neededWhat is needed

Introduction

Overview

about

MBeans

and

GBeans

Java

Management

Extension

Geronimo

hosting

our

Monitor

Component

Geronimo

Beans

AnchorGeronimo BeansGeronimo Beans

The Server-Side Monitor Component

Geronimo Architecture Overview

Servlets

under

observation

Server-Side

Monitor

Component

The Monitor GBean

The AverageBuilder Thread

Deploying

the

Server-Side

Monitor

Component

Deployment Plans for Geronimo's

GBeans

The ``environment''

part:

The ``gbean''

part:

Testing the Monitor Component

Accessing Geronimo using JConsole

Interacting with the Monitor Component: ServletMonitorGBean

Conclusion

References

Anchor
What is needed
What is needed

Anchor
Geronimo Beans
Geronimo Beans