[HBASE-16910] Avoid NPE when starting StochasticLoadBalancer

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 1.4.0, 1.3.3, 2.0.0
• Component/s: Balancer
• Hadoop Flags: Reviewed
• Assignee: Guanghao Zhang
• Reporter: Guanghao Zhang
• Created: 21/Oct/16 08:19
• Updated: 14/Dec/18 10:08
• Resolved: 21/Oct/16 17:26

Description

When master start, it initialize StochasticLoadBalancer.

this.balancer.setClusterStatus(getClusterStatus());
this.balancer.setMasterServices(this);

It first setClusterStatus(), then setMasterService(). But in setClusterStatus method, it use master service which is not initialized. So it will throw NPE.

int tablesCount = isByTable ? services.getTableDescriptors().getAll().size() : 1;

It happens when set isByTable is ture.