NullPointerException was thrown while the node was starting

[halibobo1205]

Software Versions

OS : Linux
JVM : Oracle Corporation 1.8.0_161 amd64
Git : e811def
Version : 4.7.7
Code : 18386

Expected behavior

NullPointerException should not be thrown, blocks can be synced quickly.

Actual behavior

After startup, blocks are not synced fast, and NullPointerException is thrown.

Frequency

Occasionally, not always.

Backtrace

21:44:43.100 ERROR [sync-handle-block] [net](SyncService.java:315) Process sync block Num:59376024,ID:00000000038a019878cb2e751e2f31d0ff2b67ebab4a15c7cc27225fa1e856a1 failed
java.lang.NullPointerException: null
 at org.tron.consensus.Consensus.receiveBlock(Consensus.java:31)
 at org.tron.core.db.Manager.pushBlock(Manager.java:1267)
 at org.tron.core.net.TronNetDelegate.processBlock(TronNetDelegate.java:270)
 at org.tron.core.net.service.sync.SyncService.processSyncBlock(SyncService.java:306)
 at org.tron.core.net.service.sync.SyncService.lambda$handleSyncBlock$9(SyncService.java:292)
 at java.util.concurrent.ConcurrentHashMap.forEach(ConcurrentHashMap.java:1597)
 at org.tron.core.net.service.sync.SyncService.handleSyncBlock(SyncService.java:271)
 at org.tron.core.net.service.sync.SyncService.lambda$init$1(SyncService.java:88)
 at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
 at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
 at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
 at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
 at java.lang.Thread.run(Thread.java:748)

[SeriousCoding789]

@halibobo1205 Could you reproduce it easily? As this transaction happen on 2024-02-24 08:28:57, there is a database snapshot on http://34.143.247.77/backup20240222/.

[halibobo1205]

@Sunny6889 Consensus.java:31 is consensusInterface.receiveBlock(blockCapsule);, consensusInterface is Null? It doesn't seem to be affected by a specific block.

public class Consensus {

  @Autowired
  private DposService dposService;

  private ConsensusInterface consensusInterface;

  public void start(Param param) {
    consensusInterface = dposService;
    consensusInterface.start(param);
  }

  public void stop() {
    consensusInterface = dposService;
    consensusInterface.stop();
  }

  public void receiveBlock(BlockCapsule blockCapsule) {
    consensusInterface.receiveBlock(blockCapsule); // line 31
  }

  public boolean validBlock(BlockCapsule blockCapsule) {
    return consensusInterface.validBlock(blockCapsule);
  }

  public boolean applyBlock(BlockCapsule blockCapsule) {
    return consensusInterface.applyBlock(blockCapsule);
  }

}

[halibobo1205]

I'd also like to ask why we need the consensusInterface, instead of just using the dposService.

[SeriousCoding789]

In https://github.com/tronprotocol/java-tron/tree/develop/framework/src/main/java/org/tron/common/application/ApplicationImpl.java startup() function, the net service is started first, then comes consensusService. Is it caused by this order?

public void startup() {
   this.initServices(Args.getInstance());
   this.startServices();
   if ((!Args.getInstance().isSolidityNode()) && (!Args.getInstance().isP2pDisable())) {
     tronNetService.start();
   }
   consensusService.start();
   MetricsUtil.init();
 }

[halibobo1205]

@Sunny6889, It looks like tronNetService depends on consensusService, adjust the consensusService to start first.

public void startup() {
   this.initServices(Args.getInstance());
   this.startServices();
   consensusService.start();
   if ((!Args.getInstance().isSolidityNode()) && (!Args.getInstance().isP2pDisable())) {
     tronNetService.start();
   }
   MetricsUtil.init();
 }

[halibobo1205]

fixed by #6216.