Fix weak refs with network store IIDM

[geofjamg]

Signed-off-by: Geoffroy Jamgotchian geoffroy.jamgotchian@gmail.com

Please check if the PR fulfills these requirements (please use '[x]' to check the checkboxes, or submit the PR and then click the checkboxes)

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem ? If so, link to this issue using '#XXX' and skip the rest
No

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
Bug fix.

What is the current behavior? (You can also link to an open issue here)
Weak references to IIDM objects added to support fast cache restart are not compatible with network IIDM implementation as calculated bus are not attached to the network but just returned by the topology calculation (and a different object is returned at each get).

loadflow-server_1                | 
loadflow-server_1                | java.lang.NullPointerException: Reference has been garbage collected
loadflow-server_1                | 	at java.base/java.util.Objects.requireNonNull(Objects.java:246) ~[na:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.network.impl.Ref.get(Ref.java:24) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.network.impl.LfBusImpl.getBus(LfBusImpl.java:55) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.network.impl.LfBusImpl.updateState(LfBusImpl.java:90) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.network.LfNetwork.updateState(LfNetwork.java:307) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.OpenLoadFlowProvider.runAc(OpenLoadFlowProvider.java:130) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at com.powsybl.openloadflow.OpenLoadFlowProvider.lambda$run$2(OpenLoadFlowProvider.java:238) ~[powsybl-open-loadflow-1.0.0.jar:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1700) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.exec(CompletableFuture.java:1692) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594) ~[na:na]
loadflow-server_1                | 	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183) ~[na:na]

What is the new behavior (if this is a feature change)?
When network cache is not enabled we use strong references.

Does this PR introduce a breaking change or deprecate an API? If yes, check the following:

• The Breaking Change or Deprecated label has been added
• The migration guide has been updated in the github wiki (What changes might users need to make in their application due to this PR?)

Other information:

(if any of the questions/checkboxes don't apply, please delete them entirely)

[annetill]

NodeBreakerTraverser: this class is using Network and many IIDM objets.
Networks: it seems that we are doing a state reset for DC loadflow. It is an issue for network in cache in DC loadflow engine?
Contingences and actions also need the Network: I think we need to forbid cache for security analysis and sensitivity analysis.
Our feature is not compatible with VSC converter station targetV change because we rely on the HVDC and both converter stations. So we have to keep that in mind for next steps.
in AbstractLfBranch, we manipulate ratioTapChanger and phaseTapChanger for the update.
In LfHvdcImpl, we manipulate the extension HvdcAngleDrooÂctivePowerExtension.

[geofjamg]

NodeBreakerTraverser: this class is using Network and many IIDM objets.
Networks: it seems that we are doing a state reset for DC loadflow. It is an issue for network in cache in DC loadflow engine?
Contingences and actions also need the Network: I think we need to forbid cache for security analysis and sensitivity analysis.
Our feature is not compatible with VSC converter station targetV change because we rely on the HVDC and both converter stations. So we have to keep that in mind for next steps.
in AbstractLfBranch, we manipulate ratioTapChanger and phaseTapChanger for the update.
In LfHvdcImpl, we manipulate the extension HvdcAngleDrooÂctivePowerExtension.

I deactivated caching for DC LF, AC & DC AS, AC & DC sensi.

[sonarqubecloud]

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0 Bugs
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100.0% Coverage
0.0% Duplication