Multiple duplicate element IDs cause excess memory allocations and looping.

[tbitonti]

Describe the bug

When using at least two levels of nested elements and several child elements with the same ID, memory usage quickly becomes excessive and is likely to result in running out of heap space.

Original description:
The problem is excess memory usage, and there appears to be an infinite loop in configuration merge processing.

Using a custom connection type, with references from each custom connection to a connection factory, if the connection factories are properly given unique IDs, the configuration is processed as expected.

The problem occurs If the connection factory IDs are incorrectly set to the same value.

See the attachments:

Stack of note:
stack.txt
(In particular, "com.ibm.ws.config.xml.internal.ConfigElement.merge".)

Leak suspects:
memory.txt
(In particular "com.ibm.ws.config.xml.internal.SimpleElement".)

Working configuration:
config_working.txt

Failing configuration:
config_failing.txt

The change between the configurations is the reuse of the connection factory IDs:

  <customConnection id="cc0001" connectionFactoryRef="cf0001"/>
  <connectionFactory id="cf0001">
    <properties.xx hostName="000.00.000.0" portNumber="0001"/>
  </connectionFactory>

  <customConnection id="cc0002" connectionFactoryRef="cf0002"/>
  <connectionFactory id="cf0002">
    <properties.xx hostName="000.00.000.0" portNumber="0002"/>
  </connectionFactory>

  <customConnection id="cc0001" connectionFactoryRef="cf0001"/>
  <connectionFactory id="cf0001">
    <properties.xx hostName="000.00.000.0" portNumber="0001"/>
  </connectionFactory>

  <customConnection id="cc0002" connectionFactoryRef="cf0001"/>
  <connectionFactory id="cf0001">
    <properties.xx hostName="000.00.000.0" portNumber="0002"/>
  </connectionFactory>