泛型相关的有关问题

泛型相关的问题
Map<String, RuntimeMonitor.ProcessCHeapInfo> gap = rt.getCHeap();
Iterator it = gap.entrySet().iterator();


就这么段代码，为什么第2行那里仍旧会提示 Iterator is a raw type.References to generic type Iterator<E>should be parameterized

...至今对泛形一头雾水，请各位大大指点一二

[解决办法]
Iterator <Map.Entry <String,RuntimeMonitor.ProcessCHeapInfo > > it = gap.entrySet().iterator();