Map 的两种遍历方法详细说明

//方法一   
Set<String> set = map.keySet();    
for (String s:set) {   
 System.out.println(s+","+map.get(s));   
}   

//方法二:将Map集合中的映射关系(Map.Entry类型的)取出，存入到Set集合中  for 

Iterator it = tempMap.entrySet().iterator();
   while (it.hasNext()) {
    Map.Entry entry = (Map.Entry) it.next();
    Object key = entry.getKey();
    Object value = entry.getValue();
    System.out.println("key=" + key + " value=" + value);
}

// 方法三 

for (Map.Entry entry : tempMap.entrySet()) {
    String key = entry.getKey().toString();
    String value = entry.getValue().toString();
    System.out.println("key=" + key + " value=" + value);
   }