怎样从map中取数据？

Question

我用mysql的queryforMap("select id,name from table1");查询结果是一个Map
我怎样才能把id,name的值一组一组循环得到呢？

Answer 1

mport java.util.*;
public class HashMapDemo{
        public static void main(String [] args){
                HashMap emPhone = new HashMap();
                emPhone.put("name1","111-222-3333");
                emPhone.put("name2","444-555-6666");
                emPhone.put("name3","777-888-9999");
                Set keys = emPhone.keySet();//Set类可以获取HashMap对象的键。
                Iterator keyIter = keys.iterator();
                while(keyIter.hasNext()){
                        String nextName = (String)keyIter.next();
                        String phoneNum = (String)emPhone.get(nextName);
                        System.out.println(nextName + ":" + phoneNum);
                }  
                System.out.println("---------------------------------");                
                String phoneName = (String)emPhone.remove("name1");
                System.out.println("Removed name1 :" + phoneName);
                HashMap newEmpPhone = new HashMap();
                newEmpPhone.putAll(emPhone);
                int dirSize = newEmpPhone.size();
                System.out.println("Created new phone directory with " + dirSize + "numbers...");
                phoneName = (String)newEmpPhone.get("name3");
                System.out.println("name3 number in new director: " + phoneName);
        }
} 
显示效果：
name2:444-555-6666
name3:777-888-9999
name1:111-222-3333
---------------------------------
Removed name1 :111-222-3333
Created new phone directory with 2numbers...
name3 number in new director: 777-888-9999

Answer 2

for(Iterator i = map.entrySet().iterator();i.hasNext();){
  Map.Entry e = (Map.Entry)i.next();
  System.out.println(e.key());
  System.out.println(e.value());
}