如何避免執行循環外的代碼

Question

我有一種方法，其中我比較for循環內的arraylist值。 如果loop1有任何單個條件為真，我就不想執行Loop 2 （請參見下面的代碼）。

現在的問題是，對於某些值， loop 1可以統計，而對於某些其他值， loop 2可以滿足。由於這個原因，我在db中填充了錯誤的數據。

我想以這種方式修改我的代碼。 如果任何數組列表值滿足loop 1則編譯器應從return ERROR 。 在那之后它不應該執行代碼。

循環檢查條件為if(quant>Integer.parseInt(book.getQuantity()))

Action.java。

    public String execute()
{   
      if(id.length == quantity.length)
    {
      for (int i = 0; i < id.length; ++i)
       { 
         book = dao.listbookdetailsByBId(id[i]);
         Double dq=new Double(quantity[i]);
         int quant=dq.intValue();  
          if(quant>Integer.parseInt(book.getQuantity()))
          {   
                 //Loop 1  , this is executing if any of the quant is greater then book.getQuantity()..                    
                //i want to stop executing LOOP2 ,if any of the value of quant is greater then book.getQuantity().
              addActionError("You have entered an invalid quantity for the Book Title- ''"+book.getBookTitile()+"''."); 
              return ERROR; 
          }   

    /*  Loop2 starts here
    *   Loop 2 , this is executing if any of the quant is lesser .. 
    *   The below code should execute only if compiler does not reach to the loop1 */

                      // Some DAO code goes here

       }
    }

    return SUCCESS;
}

Answer 1

只需使用break語句

if(quant>Integer.parseInt(book.getQuantity()))
      {   
             //Loop 1  , this is executing if any of the quant is greater then book.getQuantity()..                    
            //i want to stop executing LOOP2 ,if any of the value of quant is greater then book.getQuantity().
          addActionError("You have entered an invalid quantity for the Book Title- ''"+book.getBookTitile()+"''."); 
          break; 
      }

Answer 2

您應該使用break語句來實現此目的，或者可以創建一個局部布爾變量，並使用它避免進入循環2。

    if(quant>Integer.parseInt(book.getQuantity()))
          { flag=false;
}

if(flag){
//loop 2
}