Review <Map> element in Jetty XML

[sbordet]

Jetty version
10.0.x

Description
The <Map> element is not used in Jetty XML files.

It cannot be customized to create Map implementations, it only creates HashMaps.

<Map> takes a list of <Entry> elements, but <Entry> takes a list of 2 <Item>, which is error prone (e.g. pass a number of items different from 2).

There is <Put> already that however is constrained to have a literal key in the name attribute (e.g. the key cannot be the result of a <SystemProperty>), which works with any Map implementations, for example java.util.Properties.

In summary, I think <Map> should be removed. Specific implementations can be created with <New>, and <Put> covers most cases. For the non covered cases, we can always use <Call>.

[gregw]

I don't think we can remove it without deprecating it for some time first.
Also I'd like to see Put enhanced to support:

  <Put>
    <Key>name</Key>
    <Value>value</Value>
  </Put>

Which is on trend for removing values from element parameters anyway!

If we can do that quickly.. then maybe we can just remove Map and have a configuration-10.dtd

BUT IT HAS TO BE DONE TODAY if it is to make it into 10.0.x

[sbordet]

Added class attribute and Class element to Map so that the implementation can be specified.

The other proposed changes were either backwards incompatible or too complex.