問題描述

我已經成功編譯了我的庫存程序:

//Inventory.java 第 1 部分//這個程序是計算電子部相機庫存的價值導入 java.util.*；導入 javax.swing.*；導入 java.awt.event.*；導入java.io.*；公共類庫存{公共靜態無效主要(字符串 [] 參數){//創建掃描器以從命令窗口獲取輸入掃描儀輸入 = 新掃描儀(System.in)；字符串名稱；int 項目編號；//第一個要相乘的數字int itemStock;//第二個要相乘的數字雙項價格；//雙倍總價值；//number1 和 number2 的乘積while(true){//無限循環//創建新的相機對象System.out.print("請輸入部門名稱:");//迅速的String itemDept = input.nextLine();//讀取用戶名if(itemDept.equals("stop"))//退出循環休息;{System.out.print("請輸入項目名稱:");//迅速的名稱 = input.nextLine();//讀取用戶的第一個數字input.nextLine();}System.out.print("請輸入商品編號:");//迅速的itemNumber = input.nextInt();//讀取用戶的第一個數字input.nextLine();而(項目編號 <= -1){System.out.print("請輸入有效數字:");//迅速的itemNumber = input.nextInt();//從用戶 input.nextLine() 中讀取第一個數字；}/* while 語句，條件是輸入負數提示用戶輸入正數 */System.out.print("輸入手頭的物品數量:");//迅速的itemStock = input.nextInt();//讀取用戶的第一個數字input.nextLine();而(項目庫存 <= -1){System.out.print("輸入正數的手頭物品數:");//迅速的itemStock = input.nextInt();//讀取用戶的第一個數字input.nextLine();}/* while 語句，條件是輸入負數提示用戶輸入正數 */System.out.print("輸入商品價格:");//迅速的itemPrice = input.nextDouble();//從用戶那里讀取第二個數字input.nextLine();而(項目價格 <= -1){System.out.print("請輸入商品價格的正數:");//迅速的itemPrice = input.nextDouble();//讀取用戶的第一個數字input.nextLine();}/* while 語句，條件是輸入負數提示用戶輸入正數 */Cam camera = new Cam(name, itemNumber, itemStock, itemPrice);totalValue = itemStock * itemPrice;//乘數System.out.println("部門名稱:" + itemDept);//顯示部門名稱System.out.println("物品編號:" + camera.getItemNumber());//顯示商品編號System.out.println("產品名稱:" + camera.getName());//顯示項目System.out.println("數量:" + camera.getItemStock());System.out.println("單價" + camera.getItemPrice());System.out.printf("總值為:$%.2f
" + totalValue);//顯示產品}//結束 while 方法}//結束方法 main}/* 結束類庫存 */類凸輪{私有字符串名稱；私人 int itemNumber;私有 int itemStock;私人雙項價格；私人字符串部門名稱；公共凸輪(字符串名稱，int itemNumber，int itemStock，double itemPrice){this.name = 名稱；this.itemNumber = itemNumber;this.itemStock = itemStock;this.itemPrice = itemPrice;}公共字符串 getName(){返回名稱；}公共 int getItemNumber(){返回項目編號；}公共 int getItemStock(){返回項目庫存；}公共雙 getItemPrice(){返回項目價格；}}

<塊引用>

C:Java>java 庫存
輸入部門名稱:電子
輸入項目名稱:相機
輸入貨號:12345
輸入手頭的物品數量:8
輸入商品價格:100.50
部門名稱:電子學
貨號:12345
產品名稱:相機
數量:8
單價100.5
總值是:
線程主"java.util.MissingFormatArgumentException 中的 $Exception:
格式說明符.2f"
在 java.util.Formatter.format(未知來源)
在 java.io.PrintStream.format(未知來源)
在 java.io.PrintStream.printf(未知來源)
在 Inventory.main(Inventory.java:82)

我似乎遇到了這種格式錯誤，不明白為什么.

如果你使用printf，你需要將占位符指定為printf參數以及格式細繩.在您的情況下，您通過附加金額來傳遞單個字符串，因此會出現錯誤.

System.out.printf("總值為:$%.2f
" + totalValue)

應該替換為

System.out.printf("總值為:$%.2f
", totalValue)

I have been successful in compiling my inventory program:

// Inventory.java part 1
// this program is to calculate the value of the inventory of the Electronics Department's cameras

import java.util.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;

public class Inventory
{
   public static void main(String[] args)
   {
       // create Scanner to obtain input from the command window
       Scanner input = new Scanner (System.in);

       String name;
       int itemNumber; // first number to multiply
       int itemStock; // second number to multiply
       double itemPrice; //
       double totalValue; // product of number1 and number2



   while(true){       // infinite loop
              // make new Camera object

      System.out.print("Enter Department name: "); //prompt
      String itemDept = input.nextLine(); // read name from user

            if(itemDept.equals("stop"))  // exit the loop
           break;


 {
 System.out.print("Enter item name: "); // prompt
 name = input.nextLine(); // read first number from user
 input.nextLine();


     }

 System.out.print("Enter the item number: "); // prompt
 itemNumber = input.nextInt(); // read first number from user
 input.nextLine();
  while( itemNumber <= -1){
 System.out.print("Enter valid number:"); // prompt
 itemNumber = input.nextInt(); // read first number from user input.nextLine();
 } /* while statement with the condition that negative numbers are entered
 user is prompted to enter a positive number */

 System.out.print("Enter number of items on hand: "); // prompt
 itemStock = input.nextInt(); // read first number from user
 input.nextLine();
  while( itemStock <= -1){
 System.out.print("Enter positive number of items on hand:"); // prompt
 itemStock = input.nextInt(); // read first number from user
 input.nextLine();
 } /* while statement with the condition that negative numbers are entered
 user is prompted to enter a positive number */

 System.out.print("Enter item Price: "); // prompt
 itemPrice = input.nextDouble(); // read second number from user
 input.nextLine();
  while( itemPrice <= -1){
 System.out.print("Enter positive number for item price:"); // prompt
 itemPrice = input.nextDouble(); // read first number from user
 input.nextLine();
 } /* while statement with the condition that negative numbers are entered
 user is prompted to enter a positive number */


 Cam camera = new Cam(name, itemNumber, itemStock, itemPrice);

 totalValue = itemStock * itemPrice; // multiply numbers

 System.out.println("Department name:" + itemDept); // display Department name
 System.out.println("Item number: " + camera.getItemNumber()); //display Item number
 System.out.println("Product name:" + camera.getName()); // display the item
 System.out.println("Quantity: " + camera.getItemStock());
 System.out.println("Price per unit" + camera.getItemPrice());
 System.out.printf("Total value is: $%.2f
" + totalValue); // display product

       } // end while method

   } // end method main

}/* end class Inventory */

class Cam{

private String name;
private int itemNumber;
private int itemStock;
private double itemPrice;
private String deptName;

public Cam(String name, int itemNumber, int itemStock, double itemPrice) {
this.name = name;
this.itemNumber = itemNumber;
this.itemStock = itemStock;
this.itemPrice = itemPrice;
   }

   public String getName(){
      return name;
      }



   public int getItemNumber(){
   return itemNumber;

}

   public int getItemStock(){
   return itemStock;

}

   public double getItemPrice(){
    return itemPrice;

}

}

C:Java>java Inventory
Enter Department name: Electronics
Enter item name: camera
Enter the item number: 12345
Enter number of items on hand: 8
Enter item Price: 100.50
Department name:Electronics
Item number: 12345
Product name:camera
Quantity: 8
Price per unit100.5
Total value is:
$Exception in thread "main" java.util.MissingFormatArgumentException:
Format specifier '.2f'
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at Inventory.main(Inventory.java:82)

I seem to come to this format error and cannot see why.

If you are using printf, you need to specify the placeholders as printf parameters along with the format string. In your case you are passing a single string by appending the amount hence the error.

System.out.printf("Total value is: $%.2f
" + totalValue)

should be replaced by

System.out.printf("Total value is: $%.2f
", totalValue)

這篇關于MissingFormatArgumentException 錯誤的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！