优化几个循环的方法

Question

我有一个方法，有几个错综复杂的for和if语句。由于该应用程序仍在开发中，资源使用并不重要，但我想知道是否有某种优化方法，因为它看起来非常沉重。

这一切都归结到这一点：如果我有几个映射Object，有没有办法在我的对象之一（已知）现场检查的值，如果这个值被满足，更新所有的人都用相同的值，而不会在我的地图上迭代太多次。

下面的代码

private Map<Integer, Reservation> CreerMapFax(HttpServletRequest request, HttpSession session) 
{ 
    // Get the "keys" parameter array from the request 
    // and makes an array of integers 
    String[] strKeys = request.getParameterValues("keys"); 
    Integer[] intKeys = new Integer[strKeys.length]; 
    for (int i = 0; i < strKeys.length; i++) 
     intKeys[i] = Integer.parseInt(strKeys[i]); 

    // Creates Map (1) of the selected bookings that need to be faxed, 
    // gets Map (2) of all registered bookings within session 
    // and fill (1) with data from (2) 
    // by using the keys stored in the array 
    boolean mail = true; 

    Map<Integer, Booking> mapFax = new HashMap<Integer, Booking>(); 
    Map<Integer, Booking> bookings= 
      (HashMap<Integer, Booking>) session.getAttribute(SESSION_BOOKINGS); 

    for (int i = 0; i < intKeys.length; i++) 
    { 
     Booking booking = bookingss.get(intKeys[i]); 
     if (!booking.getMailing()) 
      mail = false; 

     // Some updating done here on "booking" 
     ... 

     // Overwrite old map values with new ones 
     bookings.put(intKeys[i], booking); 
     mapFax.put(intKeys[i], booking); 

    } 

    // mail == false whenever at least one of the booking 
    // stored in the map had their getMailing() method return false 

    if (!mail) 
    { 
     for (int j = 0; j < intKeys.length; j++) 
     { 
      // Updates AGAIN ! 
      Booking booking = mapFax.get(intKeys[j]); 
      booking.setMailing(false); 
      mapFax.put(intKeys[j], booking); 
      reservations.put(intKeys[j], booking); 
     } 
    } 

    session.setAttribute(SESSION_BOOKINGS, BOOKINGS); 
    return mapFax; 
} 

基本上，这是什么目的这样做（除了更新Booking对象的其他领域并返回mapFax地图作进一步处理）是设置邮件领域的虚假每个以及如果至少有一个值设置为false，则mapFax中的每个对象。

如果for(){if(){}}后跟if(){for(){}}，我想知道是否有某种方法可以使它更加高效和可读？

Answer 1

我会首先查找邮件标记（破一旦发现环路），然后会做所有的更新都在一个圈......

这样的事情...

... 
for (int i = 0; i < intKeys.length; i++) 
{ 
    Booking booking = bookingss.get(intKeys[i]); 
    if (!booking.getMailing()) 
    { 
     mail = false; 
     break; 
    } 
} 
.... 
for (int i = 0; i < intKeys.length; i++) 
{ 
    // Some updating done here on "booking" 
    ...  
    if (!mail) 
    { 
     ... 
    } 
    ... 
    // Overwrite old map values with new ones 
    bookings.put(intKeys[i], booking); 
    mapFax.put(intKeys[i], booking); 
}  

Answer 2

private Map<Integer, Reservation> CreerMapFax(HttpServletRequest request, HttpSession session) { 
    String[] strKeys = request.getParameterValues("keys"); 
    Integer[] intKeys = new Integer[strKeys.length]; 
    for (int i = 0; i < strKeys.length; i++) { 
     intKeys[i] = Integer.parseInt(strKeys[i]); 
    } 

    boolean mail = true; 

    Map<Integer, Booking> mapFax = new HashMap<Integer, Booking>(); 
    Map<Integer, Booking> bookings= (HashMap<Integer, Booking>) session.getAttribute(SESSION_BOOKINGS); 

    for (Integer intKey : intKeys) { 
     Booking booking = bookingss.get(intKey); 
     if (!booking.getMailing()) { 
      mail = false; 
      break; 
     } 
    } 

    for(Integer intKey : intKeys) { 
     Booking booking = mapFax.get(intKey); 
     mapFax.put(intKey, booking); 
     if(!mail) { 
      booking.setMailing(false); 
      reservations.put(intKey, booking); 
     } 
    } 

    session.setAttribute(SESSION_BOOKINGS, BOOKINGS); 
    return mapFax; 
}