Kotlin HashMap

遍历Map

获取键值的队列，通过键值进行遍历

val people = HashMap<String,String>()
people["xiao"] = "ming"
people["liu"] = "huan"
for(key in people.keys){
     print("$key:${people[key]}")
     //如果是要同时获取键和值，建议直接用entrySet性能上会更好一些
}

利用entrySet方法：（需同时获取键及值的情况下性能最佳）

Map map = new HashMap();
Iterator iter = map.entrySet().iterator();
while (iter.hasNext()) {
Map.Entry entry = (Map.Entry) iter.next();
   Object key = entry.getKey();
   Object val = entry.getValue();
}

for循环

Map<String, String> map = new HashMap<String, String>();
for (Entry<String, String> entry : map.entrySet()) {
    entry.getKey();
    entry.getValue();
}

Map<String, String> map = new HashMap<String, String>();
for (String key : map.keySet()) {
    map.get(key);
}