Examples of errors detected by the V6082 diagnostic

V6082. Unsafe double-checked locking.

WildFly

V6082 Unsafe double-checked locking. A previously assigned object may be replaced by another object. JspApplicationContextWrapper.java(74), JspApplicationContextWrapper.java(72)

private volatile ExpressionFactory factory;
....
@Override
public ExpressionFactory getExpressionFactory() {
  if (factory == null) {
    synchronized (this) {
      if (factory == null) {
        factory = delegate.getExpressionFactory();
        for (ExpressionFactoryWrapper wrapper : wrapperList) {
          factory = wrapper.wrap(factory, servletContext);
        }
      }
    }
  }
  return factory;
}

DBeaver

V6082 Unsafe double-checked locking. The field should be declared as volatile. TaskImpl.java(59), TaskImpl.java(317)

private List<DBTTaskRun> runs;
....
private void loadRunsIfNeeded() {
    if (runs == null) {
        synchronized (this) {
            if (runs == null) {
                runs = new ArrayList<>(loadRunStatistics());
            }
        }
    }
}

Keycloak

V6082 Unsafe double-checked locking. The field should be declared as volatile. WelcomeResource.java 77 , WelcomeResource.java 257

public class WelcomeResource {
  private AtomicBoolean shouldBootstrap;

  ....

  private boolean shouldBootstrap() {
    if (shouldBootstrap == null) {
      synchronized (this) {
        if (shouldBootstrap == null) {
          shouldBootstrap = new AtomicBoolean(....);
        }
      }
    }
    return shouldBootstrap.get();
  }

Keycloak

V6082 Unsafe double-checked locking. The field should be declared as volatile. DefaultFreeMarkerProviderFactory.java 13 , DefaultFreeMarkerProviderFactory.java 20

public class DefaultFreeMarkerProviderFactory
  implements FreeMarkerProviderFactory {

    private DefaultFreeMarkerProvider provider;   // <=

    ....

    public DefaultFreeMarkerProvider create(KeycloakSession session) {
      if (provider == null) {
        synchronized (this) {
          if (provider == null) {
            if (Config.scope("theme").getBoolean("cacheTemplates", true)) {
              cache = new ConcurrentHashMap<>();
            }
            kcSanitizeMethod = new KeycloakSanitizerMethod();
            provider = new DefaultFreeMarkerProvider(cache, kcSanitizeMethod);
          }
        }
      }
      return provider;
    }
}