java遍历map

  //方法一: 用entrySet() 
   Iterator it = emails.entrySet().iterator(); 
   while(it.hasNext()){ 
    Map.Entry m=(Map.Entry)it.next(); 
    logger.info("email-" + m.getKey() + ":" + m.getValue()); 
   } 
  
   // 方法二：jdk1.5支持，用entrySet()和For-Each循环() 
   for (Map.Entry<String, String> m : emails.entrySet()) { 
   
    logger.info("email-" + m.getKey() + ":" + m.getValue()); 
   } 
  
   // 方法三：用keySet() 
   Iterator it = emails.keySet().iterator(); 
   while (it.hasNext()){ 
    String key; 
    key=(String)it.next(); 
    logger.info("email-" + key + ":" + emails.get(key)); 
   } 

// 方法四：jdk1.5支持，用keySEt()和For-Each循环 

for(Object m: emails.keySet()){ 
    logger.info("email-" + m+ ":" + emails.get(m)); 
   }