我还是很喜欢编程。我只使用了三个编程类，一个用C ++编写，两个用Java编写。
我决定要建立自己的战舰版本。我或多或少地完成了整个项目。我的问题一直是提供用户验证的方法，以确保用户实际输入有效信息。
我在嵌套的do-while循环中有大量代码，如果特定条件返回false，每个代码都会重复。
我创建了一个代表游戏板的Board类。这是减去方法的代码。
public class Board
{
// Create class-wide arrays to represent each board
private static int p1[][] = new int[10][10];
private static int p2[][] = new int[10][10];
// Create other class-wide variables
private static int p1Targets[][] = new int[10][10];
private static int p2Targets[][] = new int[10][10];
private static int boatOneLocationP1[][] = new int[2][2];
private static boolean boatOneP1Sunk = false;
private static int boatTwoLocationP1[][] = new int[3][2];
private static boolean boatTwoP1Sunk = false;
private static int boatThreeLocationP1[][] = new int[3][2];
private static boolean boatThreeP1Sunk = false;
private static int boatFourLocationP1[][] = new int[4][2];
private static boolean boatFourP1Sunk = false;
private static int boatFiveLocationP1[][] = new int[5][2];
private static boolean boatFiveP1Sunk = false;
private static int boatOneLocationP2[][] = new int[2][2];
private static boolean boatOneP2Sunk = false;
private static int boatTwoLocationP2[][] = new int[3][2];
private static boolean boatTwoP2Sunk = false;
private static int boatThreeLocationP2[][] = new int[3][2];
private static boolean boatThreeP2Sunk = false;
private static int boatFourLocationP2[][] = new int[4][2];
private static boolean boatFourP2Sunk = false;
private static int boatFiveLocationP2[][] = new int[5][2];
private static boolean boatFiveP2Sunk = false;
}
这是整个placeBoats（）方法
这是我的placeBoats（）方法。 Player类有一个静态变量，用于创建的Player对象总数，每个对象都有自己唯一的玩家编号。
void placeBoats(Player p, Scanner kb)
{
// Player is shown a menu, he must select all 5 options to place his
// boats.
// Once user has selected which boat he is placing, display the ocean
// and ask the user for start and end coordinates
// Use arrays for Menu Choices and for User Choices
int[] menuChoices = new int[5];
int[] userChoices = new int[5];
// Initialize arrays
for (int i = 0; i < userChoices.length; i++)
{
userChoices[i] = 0;
}
for (int i = 0; i < menuChoices.length; i++)
{
/*
* 1. Two-Length Ship 2. Three-Length Ship 1 3. Three-Length Ship 2
* 4. Four-Length Ship 5. Five-Length Ship
*
* Repeat the do-while loop until userChoices[] == 1.
*/
menuChoices[i] = i + 1;
}
// Begin do-while loop
int num = 0;
int boatLength = 0;
int row1 = 0, col1 = 0, row2 = 0, col2 = 0;
boolean notReady = true;
boolean boatPresent = false;
boolean validCoords = false;
String starting, ending;
do
{ // Jump to end
do
{ // Jump to Place Boats
boatPresent = false;
do
{ // Jump to boat validation (making sure no boats already exist
// in area)
validCoords = false;
// Display Menu
System.out.println("Menu");
if (menuChoices[0] == 1)
{
System.out.println("1. Two-Length Ship");
}
if (menuChoices[1] == 2)
{
System.out.println("2. Three-Length Ship 1");
}
if (menuChoices[2] == 3)
{
System.out.println("3. Three-Length Ship 2");
}
if (menuChoices[3] == 4)
{
System.out.println("4. Four-Length Ship");
}
if (menuChoices[4] == 5)
{
System.out.println("5. Five-Length Ship");
}
// Get user input
System.out.print("\nEnter your menu choice: ");
num = kb.nextInt();
kb.nextLine();
// Input Validation- input must be a valid menu choice
while ((num != 1 && num != 2 && num != 3 && num != 4 && num != 5))
{
System.out.print("Enter your menu choice: ");
num = kb.nextInt();
kb.nextLine();
}
// Further Validation- Make sure number has not been picked
// before yet
while (userChoices[num - 1] == 1)
{
System.out.print("Enter your menu choice: ");
num = kb.nextInt();
kb.nextLine();
}
// Set boat length
if (num == 1)
boatLength = 2;
if (num == 2)
boatLength = 3;
if (num == 3)
boatLength = 3;
if (num == 4)
boatLength = 4;
if (num == 5)
boatLength = 5;
// ////////////////////////////////////////////////////////////////////////////////////////
// Display ocean
if (p.getPlayerNumber() == 1)
{
showP1Board();
System.out.println();
}
if (p.getPlayerNumber() == 2)
{
showP2Board();
System.out.println();
}
// Ask the user for the start and end coordinates (as a
// String)
System.out.print("Enter the starting coordinate for a "
+ boatLength + "-length ship: \n");
starting = kb.nextLine();
// Validate - Make sure the given values are valid
while (starting.charAt(0) != 'A'
&& starting.charAt(0) != 'B'
&& starting.charAt(0) != 'C'
&& starting.charAt(0) != 'D'
&& starting.charAt(0) != 'E'
&& starting.charAt(0) != 'F'
&& starting.charAt(0) != 'G'
&& starting.charAt(0) != 'H'
&& starting.charAt(0) != 'I'
&& starting.charAt(0) != 'J'
&& starting.charAt(0) != 'a'
&& starting.charAt(0) != 'b'
&& starting.charAt(0) != 'c'
&& starting.charAt(0) != 'd'
&& starting.charAt(0) != 'e'
&& starting.charAt(0) != 'f'
&& starting.charAt(0) != 'g'
&& starting.charAt(0) != 'h'
&& starting.charAt(0) != 'i'
&& starting.charAt(0) != 'j')
{
System.out.print("Enter the starting coordinate for a "
+ boatLength + "-length ship: ");
starting = kb.nextLine();
}
while (starting.charAt(1) != '1'
&& starting.charAt(1) != '2'
&& starting.charAt(1) != '3'
&& starting.charAt(1) != '4'
&& starting.charAt(1) != '5'
&& starting.charAt(1) != '6'
&& starting.charAt(1) != '7'
&& starting.charAt(1) != '8'
&& starting.charAt(1) != '9')
{
System.out.print("Enter the starting coordinate for a "
+ boatLength + "-length ship: ");
starting = kb.nextLine();
}
System.out.println("[" + starting.charAt(0) + "]["
+ starting.charAt(1) + "]");
System.out.println();
// Set Row and Column 1
switch (starting.charAt(0))
{
case 'a':
case 'A':
row1 = 0;
break;
case 'b':
case 'B':
row1 = 1;
break;
case 'c':
case 'C':
row1 = 2;
break;
case 'd':
case 'D':
row1 = 3;
break;
case 'e':
case 'E':
row1 = 4;
break;
case 'f':
case 'F':
row1 = 5;
break;
case 'g':
case 'G':
row1 = 6;
break;
case 'h':
case 'H':
row1 = 7;
break;
case 'i':
case 'I':
row1 = 8;
break;
case 'j':
case 'J':
row1 = 9;
break;
} // end switch statement
switch (starting.charAt(1))
{
case 49:
case 1:
col1 = 0;
break;
case 50:
case 2:
col1 = 1;
break;
case 51:
case 3:
col1 = 2;
break;
case 52:
case 4:
col1 = 3;
break;
case 53:
case 5:
col1 = 4;
break;
case 54:
case 6:
col1 = 5;
break;
case 55:
case 7:
col1 = 6;
break;
case 56:
case 8:
col1 = 7;
break;
case 57:
case 9:
col1 = 8;
break;
}
System.out.println(starting.length());
if (starting.length() >= 3)
{
if ((starting.charAt(1) == 1 || starting.charAt(1) == 49)
&& (starting.charAt(2) == 0 || starting
.charAt(2) == 48))
{
col1 = 9;
}
}
System.out.println("Row1 = " + row1 + "\tCol1 = " + col1);
// //////////////////////////////////////////////////////////////////////
System.out.print("Enter the ending coordinate for a "
+ boatLength + "-length ship: \n");
ending = kb.nextLine();
// Validate - Make sure the given values are valid
while (ending.charAt(0) != 'A' && ending.charAt(0) != 'B'
&& ending.charAt(0) != 'C'
&& ending.charAt(0) != 'D'
&& ending.charAt(0) != 'E'
&& ending.charAt(0) != 'F'
&& ending.charAt(0) != 'G'
&& ending.charAt(0) != 'H'
&& ending.charAt(0) != 'I'
&& ending.charAt(0) != 'J'
&& ending.charAt(0) != 'a'
&& ending.charAt(0) != 'b'
&& ending.charAt(0) != 'c'
&& ending.charAt(0) != 'd'
&& ending.charAt(0) != 'e'
&& ending.charAt(0) != 'f'
&& ending.charAt(0) != 'g'
&& ending.charAt(0) != 'h'
&& ending.charAt(0) != 'i'
&& ending.charAt(0) != 'j')
{
System.out.print("Enter the ending coordinate for a "
+ boatLength + "-length ship: ");
ending = kb.nextLine();
}
while (ending.charAt(1) != '1' && ending.charAt(1) != '2'
&& ending.charAt(1) != '3'
&& ending.charAt(1) != '4'
&& ending.charAt(1) != '5'
&& ending.charAt(1) != '6'
&& ending.charAt(1) != '7'
&& ending.charAt(1) != '8'
&& ending.charAt(1) != '9')
{
System.out.print("Enter the ending coordinate for a "
+ boatLength + "-length ship: ");
ending = kb.nextLine();
}
System.out.println("[" + ending.charAt(0) + "]["
+ ending.charAt(1) + "]");
System.out.println();
// Set Row and Column 2
switch (ending.charAt(0))
{
case 'a':
case 'A':
row2 = 0;
break;
case 'b':
case 'B':
row2 = 1;
break;
case 'c':
case 'C':
row2 = 2;
break;
case 'd':
case 'D':
row2 = 3;
break;
case 'e':
case 'E':
row2 = 4;
break;
case 'f':
case 'F':
row2 = 5;
break;
case 'g':
case 'G':
row2 = 6;
break;
case 'h':
case 'H':
row2 = 7;
break;
case 'i':
case 'I':
row2 = 8;
break;
case 'j':
case 'J':
row2 = 9;
break;
} // end switch statement
switch (ending.charAt(1))
{
case 49:
case 1:
col2 = 0;
break;
case 50:
case 2:
col2 = 1;
break;
case 51:
case 3:
col2 = 2;
break;
case 52:
case 4:
col2 = 3;
break;
case 53:
case 5:
col2 = 4;
break;
case 54:
case 6:
col2 = 5;
break;
case 55:
case 7:
col2 = 6;
break;
case 56:
case 8:
col2 = 7;
break;
case 57:
case 9:
col2 = 8;
break;
}
if (ending.length() >= 3)
{
if ((ending.charAt(1) == 1 || ending.charAt(1) == 49)
&& (ending.charAt(2) == 0 || ending.charAt(2) == 48))
{
col2 = 9;
}
}
// end set rows and cols
System.out.println("Row2 = " + row2 + "\tCol2 = " + col2);
// Make sure the coordinates are valid start and end
// coordinates for the given length ship.
if (((row1 == row2) && ((col2 == col1 + (boatLength - 1)) || (col2 == col1
- (boatLength - 1))))
|| ((col1 == col2) && ((row2 == row1
+ (boatLength - 1)) || (row2 == row1
- (boatLength - 1)))))
validCoords = true;
if (!validCoords)
System.out.println("Error: Invalid coordinates for a "
+ boatLength + " -length ship.\n");
} while (!validCoords); // end inner do-while
// Make sure there is not a boat already in that area.
// Loop through part of the array and check for 1's and 2's
// (boat present on coordinate)
// If there are, a boat is present and these coordinates are
// therefore invalid.
if (p.getPlayerNumber() == 1)
{
if (row1 == row2)
{
if (col1 + boatLength > 9)
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1; c > col1 - boatLength; c--)
{
if (p1[r][c] == 1 || p1[r][c] == 2)
boatPresent = true;
}
}
} else
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1; c < col1 + boatLength; c++)
{
if (p1[r][c] == 1 || p1[r][c] == 2)
boatPresent = true;
}
}
}
} else
{
if (row1 + boatLength > 9)
{
for (int r = row1; r > row1 - boatLength; r--)
{
for (int c = col1; c < col1 + 1; c++)
{
if (p1[r][c] == 1 || p1[r][c] == 2)
boatPresent = true;
}
}
} else
{
for (int r = row1; r < row1 + boatLength; r++)
{
for (int c = col1; c < col1 + 1; c++)
{
if (p1[r][c] == 1 || p1[r][c] == 2)
boatPresent = true;
}
}
}
}
}
if (p.getPlayerNumber() == 2)
{
if (row1 == row2)
{
if (col1 + boatLength > 9)
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1; c > col1 - boatLength; c--)
{
if (p2[r][c] == 1 || p2[r][c] == 2)
boatPresent = true;
}
}
} else
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1; c < col1 + boatLength; c++)
{
if (p2[r][c] == 1 || p2[r][c] == 2)
boatPresent = true;
}
}
}
} else
{
if (row1 + boatLength > 9)
{
for (int r = row1; r > row1 - boatLength; r--)
{
for (int c = col1; c < col1 + 1; c++)
{
if (p2[r][c] == 1 || p2[r][c] == 2)
boatPresent = true;
}
}
} else
{
for (int r = row1; r < row1 + boatLength; r++)
{
for (int c = col1; c < col1 + 1; c++)
{
if (p2[r][c] == 1 || p2[r][c] == 2)
boatPresent = true;
}
}
}
}
}
if (boatPresent)
System.out
.println("Error: Invalid coordinates, a boat is present in this location.");
} while (boatPresent); // end outer do-while
// Place the boat on the ocean
if (p.getPlayerNumber() == 1)
{
if (row1 == row2)
{
if (col1 + boatLength - 1 > 9
|| (starting.charAt(1) > ending.charAt(1)))
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1, counter = 0; c > col1
- boatLength; c--, counter++)
{
// place boat
p1[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP1[counter][0] = r;
boatOneLocationP1[counter][1] = c;
break;
case 2:
boatTwoLocationP1[counter][0] = r;
boatTwoLocationP1[counter][1] = c;
break;
case 3:
boatThreeLocationP1[counter][0] = r;
boatThreeLocationP1[counter][1] = c;
break;
case 4:
boatFourLocationP1[counter][0] = r;
boatFourLocationP1[counter][1] = c;
break;
case 5:
boatFiveLocationP1[counter][0] = r;
boatFiveLocationP1[counter][1] = c;
break;
}
}
}
} else
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1, counter = 0; c < col1
+ boatLength; c++, counter++)
{
p1[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP1[counter][0] = r;
boatOneLocationP1[counter][1] = c;
break;
case 2:
boatTwoLocationP1[counter][0] = r;
boatTwoLocationP1[counter][1] = c;
break;
case 3:
boatThreeLocationP1[counter][0] = r;
boatThreeLocationP1[counter][1] = c;
break;
case 4:
boatFourLocationP1[counter][0] = r;
boatFourLocationP1[counter][1] = c;
break;
case 5:
boatFiveLocationP1[counter][0] = r;
boatFiveLocationP1[counter][1] = c;
break;
}
}
}
}
} else
// Columns the same
{
// Going backwards
if (row1 + boatLength - 1 > 9
|| (starting.charAt(0) > ending.charAt(0)))
{
for (int r = row1, counter = 0; r > row1 - boatLength; r--, counter++)
{
for (int c = col1; c < col1 + 1; c++)
{
p1[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP1[counter][0] = r;
boatOneLocationP1[counter][1] = c;
break;
case 2:
boatTwoLocationP1[counter][0] = r;
boatTwoLocationP1[counter][1] = c;
break;
case 3:
boatThreeLocationP1[counter][0] = r;
boatThreeLocationP1[counter][1] = c;
break;
case 4:
boatFourLocationP1[counter][0] = r;
boatFourLocationP1[counter][1] = c;
break;
case 5:
boatFiveLocationP1[counter][0] = r;
boatFiveLocationP1[counter][1] = c;
break;
}
}
}
} else
// going forwards
{
for (int r = row1, counter = 0; r < row1 + boatLength; r++, counter++)
{
for (int c = col1; c < col1 + 1; c++)
{
p1[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP1[counter][0] = r;
boatOneLocationP1[counter][1] = c;
break;
case 2:
boatTwoLocationP1[counter][0] = r;
boatTwoLocationP1[counter][1] = c;
break;
case 3:
boatThreeLocationP1[counter][0] = r;
boatThreeLocationP1[counter][1] = c;
break;
case 4:
boatFourLocationP1[counter][0] = r;
boatFourLocationP1[counter][1] = c;
break;
case 5:
boatFiveLocationP1[counter][0] = r;
boatFiveLocationP1[counter][1] = c;
break;
}
}
}
}
}
}
if (p.getPlayerNumber() == 2)
{
if (row1 == row2)
{
if (col1 + boatLength - 1 > 9
|| (starting.charAt(1) > ending.charAt(1)))
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1, counter = 0; c > col1
- boatLength; c--, counter++)
{
p2[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP2[counter][0] = r;
boatOneLocationP2[counter][1] = c;
break;
case 2:
boatTwoLocationP2[counter][0] = r;
boatTwoLocationP2[counter][1] = c;
break;
case 3:
boatThreeLocationP2[counter][0] = r;
boatThreeLocationP2[counter][1] = c;
break;
case 4:
boatFourLocationP2[counter][0] = r;
boatFourLocationP2[counter][1] = c;
break;
case 5:
boatFiveLocationP2[counter][0] = r;
boatFiveLocationP2[counter][1] = c;
break;
}
}
}
} else
{
for (int r = row1; r < row1 + 1; r++)
{
for (int c = col1, counter = 0; c < col1
+ boatLength; c++, counter++)
{
p2[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP2[counter][0] = r;
boatOneLocationP2[counter][1] = c;
break;
case 2:
boatTwoLocationP2[counter][0] = r;
boatTwoLocationP2[counter][1] = c;
break;
case 3:
boatThreeLocationP2[counter][0] = r;
boatThreeLocationP2[counter][1] = c;
break;
case 4:
boatFourLocationP2[counter][0] = r;
boatFourLocationP2[counter][1] = c;
break;
case 5:
boatFiveLocationP2[counter][0] = r;
boatFiveLocationP2[counter][1] = c;
break;
}
}
}
}
} else
// Columns the same
{
if (row1 + boatLength - 1 > 9
|| (starting.charAt(0) > ending.charAt(0)))
{
// Going backwards
for (int r = row1, counter = 0; r > row1 - boatLength; r--, counter++)
{
for (int c = col1; c < col1 + 1; c++)
{
p2[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP2[counter][0] = r;
boatOneLocationP2[counter][1] = c;
break;
case 2:
boatTwoLocationP2[counter][0] = r;
boatTwoLocationP2[counter][1] = c;
break;
case 3:
boatThreeLocationP2[counter][0] = r;
boatThreeLocationP2[counter][1] = c;
break;
case 4:
boatFourLocationP2[counter][0] = r;
boatFourLocationP2[counter][1] = c;
break;
case 5:
boatFiveLocationP2[counter][0] = r;
boatFiveLocationP2[counter][1] = c;
break;
}
}
}
} else
// going forwards
{
for (int r = row1, counter = 0; r < row1 + boatLength; r++, counter++)
{
for (int c = col1; c < col1 + 1; c++)
{
p2[r][c] = 1;
// Record coordinates in the static arrays for
// boat location
switch (num)
{
case 1:
boatOneLocationP2[counter][0] = r;
boatOneLocationP2[counter][1] = c;
break;
case 2:
boatTwoLocationP2[counter][0] = r;
boatTwoLocationP2[counter][1] = c;
break;
case 3:
boatThreeLocationP2[counter][0] = r;
boatThreeLocationP2[counter][1] = c;
break;
case 4:
boatFourLocationP2[counter][0] = r;
boatFourLocationP2[counter][1] = c;
break;
case 5:
boatFiveLocationP2[counter][0] = r;
boatFiveLocationP2[counter][1] = c;
break;
}
}
}
}
}
}
// userChoices[num-1] = 1; update statements
userChoices[num - 1] = 1;
menuChoices[num - 1] = 0;
// Check to see if we are ready to continue out of the loop.
notReady = true;
if (userChoices[0] == 1 && userChoices[1] == 1
&& userChoices[2] == 1 && userChoices[3] == 1
&& userChoices[4] == 1)
notReady = false;
System.out.println();
} while (notReady);
}
当我在驱动程序类中运行程序时，一切似乎都运行正常，除非在行....
// Get user input
System.out.print("\nEnter your menu choice: ");
num = kb.nextInt();
....用户输入一个字符串。在这种情况下，编译器抛出InputMismatchException。
我理解为什么我收到此错误，但如何阻止用户输入字符串？我认为我跟在用户输入行后面的两个while（）语句会处理这个问题，但是如果给出一个String，它仍会抛出异常......
有关如何解决此问题的任何想法？顺便说一句，这是我在这里的第一篇文章，很抱歉，如果我发布的代码太多了。我认为比具体而言更具体。
编辑：谢谢C.B.，ccjmne和ryvantage以及其他所有回复的人。您的所有意见都促成了我的最终解决方案，我将在下面展示。如果有更好的方法，请告诉我。//Prompt user for menu choice
try
{
// Prompt user
System.out.print("Enter your menu choice: ");
// Get input from user
num = kb.nextInt();
} catch (InputMismatchException e)
{
System.out
.println("Error, invalid input. Try again.\n");
kb.next();
}
kb.nextLine();
// Input Validation- input must be a valid menu choice
while ((num != 1 && num != 2 && num != 3 && num != 4 && num != 5))
{
try
{
// Prompt user
System.out.print("Enter your menu choice: ");
// Get input from user
num = kb.nextInt();
} catch (InputMismatchException e)
{
System.out
.println("Error, invalid input. Try again.\n");
}
kb.nextLine();
}
// Further Validation- Make sure number has not been picked
// before yet
while (userChoices[num - 1] == 1)
{
try
{
// Prompt user
System.out.print("Enter your menu choice: ");
// Get input from user
num = kb.nextInt();
} catch (InputMismatchException e)
{
System.out
.println("Error, invalid input. Try again.\n");
}
kb.nextLine();
}
答案 0 :(得分：1)
欢迎使用StackOverflow和编程世界！
您无法直接阻止用户输入[非数字]字符串。那些用户是无能为力的b * stards，只需输入任何东西，然后就可以想到：）
但是你可以做些什么。您可以让他们一次又一次地尝试，直到他们做对了！
另外，为避免抛出和捕获Exception，您可以使用Scanner#hasNextInt方法，其目的很明显。
您可以尝试执行以下操作：
while (!kb.hasNextInt()) {
kb.next(); // this will consume the rubbish input
}
num = kb.nextInt();
干杯！
答案 1 :(得分：0)
您需要catch InputMismatchException并循环回来以便继续。基本上，您的代码必须是：
while (userChoices[num - 1] == 1)
{
try {
System.out.print("Enter your menu choice: ");
num = kb.nextInt();
kb.nextLine();
} catch (InputMismatchException e) {
System.out.println("Error. Invalid input. Try again."); // Or whatever error message you want.
}
}
为了提高您的编程技巧，您应该阅读更多有关Exception handling in Java。
的信息编辑：通常，您希望避免将异常作为控制程序流的一种方法。最好的做法是通过更好的逻辑避免异常，但我真的不熟悉基于控制台的I / O，所以我不知道你是如何管理它的。特别是在解析String s中的数字时，我通常只使用try / catch hehe #guilty