New more configurable version of JMX exporter, using simpleclient.

It supports:
- Scraping the local jvm
- Scraping a remote jvm
- The existing output format by default (mostly, escaping is a bit safer, and it doesn't assume 'type' is the first beanProperty)
- Customising the name, help and labels as needed
- Exporting only what you want (only whitelist right now, blacklist would be easy to add)
- The java simpleclient

A config of 
  { "hostpost": "localhost:1234",
    "rules": [
      {"^java"}
    ]}
would export everything under java, with the default (i.e. existing) format.



I haven't written tests or the servlet bit yet, but wanted to get initial feedback on the approach.
It also puts out a metric per sample too rather than combining metrics with the same name, which isn't correct.
Thinking on it, this should really be called the jmx_collector, not the
jmx_exporter. A jmx_exporter would export to JMX (which is something we
should probably add at some point).

On 9 December 2014 at 11:32, Brian Brazil <brian.brazil@boxever.com> wrote:
>
> Done. This is a significant rewrite, so it's a good time to do it and it
> only took about 30s.
>
> On 9 December 2014 at 11:26, Björn Rabenstein <notifications@github.com>
> wrote:
>
>> In pom.xml
>> <https://github.com/prometheus/jmx_exporter/pull/4#discussion-diff-21521185>
>> :
>>
>> > @@ -5,7 +5,7 @@
>> >    <groupId>com.prometheus.jmx4prometheus</groupId>
>> >    <artifactId>jmx4prometheus</artifactId>
>> >    <packaging>jar</packaging>
>> > -  <version>0.2</version>
>> > +  <version>0.3</version>
>> >    <name>jmx4prometheus</name>
>>
>> I kind of dislike the 'prometheus' doubling in the package name. This
>> could just be 'jmx' for example ('io.prometheus.jmx'). Not sure how much
>> hassle it will cause to change it. The change is not worth a lot of
>> hassle...
>>
>> —
>> Reply to this email directly or view it on GitHub
>> <https://github.com/prometheus/jmx_exporter/pull/4/files#r21521185>.
>>
>
>