ID variables that refer to configuration files

The Liberty run time occasionally needs to refer to a configuration element from server.xml. This action can occur in several ways, such as in the text of a message or in a file name. The Liberty run time uses an xpath-style syntax to refer to configuration elements. The element type is printed first, followed by brackets containing the ID of the configuration element. If the configuration element is nested inside another configuration element, the inner configuration element is preceded with a forward slash separating the inner and outer elements.

Element ID examples

• databaseStore is not nested and has an ID value of DBTaskStore...

  <server>
    <databaseStore id="DBTaskStore">
       ...
    </databaseStore>
  </server>
  

  The element ID is...

  databaseStore[DBTaskStore]

• dataSource is nested underneath databaseStore, which has an ID value of DBTaskStore, and dataSource has an ID value of DataSource0.

  <server>
    <databaseStore id="DBTaskStore">
      <dataSource id="DataSource0">
        ...
      </dataSource>
    </databaseStore>
  </server>
  

  The element ID is...

  databaseStore[DBTaskStore]/dataSource[DataSource0]

• The configuration element does not have an ID. In this case, an ID is generated. For example, the following data source configuration element, because the databaseStore does not define an ID....

  <server>
    <databaseStore>
      <dataSource id="DataSource0">
        ...
      </dataSource>
    </databaseStore>
  </server>

  The element ID is...

  databaseStore[default-0]/dataSource[DataSource0]