here is a dump of the raw content in the mean time.

I’ve come across a few posts about Matrix Parameters recently and there is a lot of misunderstanding.

There are several old posts that discuss and describe these things:

* `Query Strings Considered Harmful `_
* `w3c MatrixURIs `_

I’ve summarised what I think is important:
– urls with query params `won’t have their response cached by intermediaries/proxies (at present)`_
– matrix parameters may appear anywhere in path
– `calculating the relative uri`_ is different
– much more than uri convention

– query params are generally abused to add new verbs instead of using existing methods on resources
– matrix parameters are not resources, they are aspects that help reference a resource in an information space that is difficult to represent within a hierarchy

**Tip: If you’re not sure if you should use them then don’t.**

Matrix parameters are used with
* `YUI paging widgets `_
* `RoR`_ /some/resource/id;edit
* J2ee fallsback to ;jsessionid=xxx when no cookies can be set.
* `Jersey (JAX-RS RefImpl) has good support `_

.. _RoR: http://rails.org

.. _won’t have their response cached by intermediaries/proxies (at present):

Caching Issues
~~~~~~~~~~~~~~~

Intermediaries (proxies) won’t cache any url with a query parameter in the url
* this is because in the early days of the web, they didn’t trust the Cache control information from dynamically generated pages.
* Freshness and Validation information are very important pieces of information and the proxy admins took a cautious stance and didn’t cache any of it.

As the web has matured the views of devs/admins are changing, the new versions of Squid will default to cache any urls with query parameters

Obviously this could have a very large impact, I’ve heard google maps image tiles had this issue with some proxies at one time.

.. _calculating the relative uri:

Relative URI calculations
~~~~~~~~~~~~~~~~~~~~~~~~~

Relative URIs have different affects, as relatives URLs are determined by appending to the Base URI. For Query Parameter requests they are stripped from the Base.

For those still interested I would recommend checking out the following in addition to the `RFC-2616 `_ of course.

* `the matrix revisited `_
* `PathsAndQueryStrings `_
* `http url path parameter syntax `_
* `Building URIs `_

http://artur.ejsmont.org/blog/PHP-Circuit-Breaker-initial-Zend-Framework-proposal

C:\usr\bin>snmpwalk -c public -v2c localhost:163 1.3.6.1.4.1.42.2.145.3.163.1.1.3.6
JVM-MANAGEMENT-MIB::jvmThreadCpuTimeMonitoring = No Such Object available on this agent at this OID

Anyone know why???

My Platform is Windows 2003 and have done the following to get Java apps monitored with Cacti.

- I have placed “JVM-MANAGEMENT-MIB.txt” in the mibs directory C:\usr\share\snmp\mibs
- changed the SNMP port TO run on port 163 instead of 161 under C:\WINDOWS\system32\drivers\etc\services
- Installed Net-SNMP and have it running as a service
- copied C:\Java\jdk-1.6-32\jre\lib\management\snmp.acl.template to copied C:\Java\jdk-1.6-32\jre\lib\management\snmp.acl
- set the following options in snmp.acl

acl ={

{

communities = public

access = read-only
managers = localhost

}

}

- Set the following parameters via wrapper.conf file for my java application:

wrapper.java.additional.1=-Dcom.sun.management.snmp.interface=0.0.0.0
wrapper.java.additional.2=-Dcom.sun.management.snmp.port=163
wrapper.java.additional.3=-Dcom.sun.management.snmp.acl=true
wrapper.java.additional.4=-Dcom.sun.management.snmp.acl.file=C:\Java\jdk-1.6-32\jre\lib\management\snmp.acl

- set the following in my snmpd.conf file:
proxy -v 2c -c public localhost:163 .1.3.6.1.4.1.42

This is a compilation of steps that I have researched and implemented.

What am I missing here? Any input would be greatly appreciated!

I left out explicit thread safety so you get to choose how much safety and liveness you want/need.

The other impl looks ok, but it is lacking in some areas, biggest one for me is: tests and logging.