GitHub user brettKK opened a pull request:
https://github.com/apache/helix/pull/201
add null check in DeplayedAutoRebalancerz#computeNewIdealState
We have developed a static analysis tool
[NPEDetector](https://github.com/lujiefsi/NPEDetector) to find some potential
NPE. Our analysis shows that some callees may return null in corner case(e.g.
node crash , IO exception), some of their callers have !=null check but some
do not have. In this issue we post a patch which can add !=null based on
existed !=null check. For example:
Callee ClusterDataCache#getStateModelDef:
```
public StateModelDefinition getStateModelDef(String stateModelDefRef) {
if (stateModelDefRef == null) {
return null;
}
return _stateModelDefMap.get(stateModelDefRef);
}
```
Caller AutoRebalancer#computeNewIdealState have !=null:
```
StateModelDefinition stateModelDef =
clusterData.getStateModelDef(stateModelName);
if (stateModelDef == null) {
LOG.error("State Model Definition null for resource: " + resourceName);
throw new HelixException("State Model Definition null for resource: " +
resourceName);
}
```
but another caller DelayedAutoRebalancer#computeNewIdealState does not have
!=null check:
```
StateModelDefinition stateModelDef =
clusterData.getStateModelDef(currentIdealState.getStateModelDefRef());
LinkedHashMap<String, Integer> stateCountMap =
stateModelDef.getStateCountMap(activeNodes.size(), replicaCount);
```
So we will add below code in non-(!=null) caller
DelayedAutoRebalancer#computeNewIdealState
```
if (stateModelDef == null) {
throw new HelixException("State Model Definition null for resource:" +
resourceName);
}
```
But due to we are not very familiar with HELIX, hope some expert can
review it.
Thanks.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/brettKK/helix HELIX-702
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/helix/pull/201.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #201
----
commit 47ea7fbad82e4c2e4c7d846c0455a0aa502f3d97
Author: brettkk <1099446733@...>
Date: 2018-04-30T03:48:01Z
add null check in DeplayedAutoRebalancerz#computeNewIdealState
----
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