MemberMBeanBridge init() {
    CachePerfStats cachePerfStats = cache.getCachePerfStats();
    addCacheStats(cachePerfStats);
    addFunctionStats(system.getFunctionStatsManager().getFunctionServiceStats());

    if (system.getDistributionManager().getStats() instanceof DistributionStats) {
      DistributionStats distributionStats =
          (DistributionStats) system.getDistributionManager().getStats();
      addDistributionStats(distributionStats);
    }

    systemStat = fetchSystemStats();

    MemoryAllocator allocator = cache.getOffHeapStore();
    if (null != allocator) {
      OffHeapMemoryStats offHeapStats = allocator.getStats();

      if (null != offHeapStats) {
        addOffHeapStats(offHeapStats);
      }
    }

    addProcessStats(fetchProcessStats());
    addStatSamplerStats(fetchStatSamplerStats());
    addVMStats(fetchVMStats());
    initializeStats();

    return this;
  }
This class acts as an Bridge between MemberMBean and GemFire Cache and Distributed System
geode-core/src/main/java/org/apache/geode/management/internal/beans/MemberMBeanBridge.java