java中map集合两种遍历方法

1.声明一个map: Map map = new HashMap();
2.向map中放值,注意：map是key-value的形式存放的.如:

map.put(”sa”,”dd”);

3.从map中取值:String str = map.get(”sa”).toString();结果是:str = ”dd”;

4.遍历一个map，从中取得key 和value

JDK1.5

Map m = new HashMap();
for (Object o : map.keySet()) {
map.get(o);
}

JDK1.4

Map map = new HashMap() ;

Iterator it = map.entrySet().iterator() ;
while (it.hasNext())
{
Map.Entry entry = (Map.Entry) it.next() ;
Object key = entry.getKey() ;
Object value = entry.getValue() ;
}