JAVA：替代break语句？

Question

For some ridiculous reason my professor has prohibited us from using break statements in our programs to terminate loops. I am making a Connect Four program and am using for loops to simulate the player dropping a checker. If my loops look like this:

for(int i = LOWEST_ROW_INDEX; i >= 0; i--)
    {
        if(gb[i][rChoice].equals(". "))
        {
            gb[i][rChoice] = "r ";
            break; //CANNOT USE BREAK
        }
    }

What could I do instead of a break statement to terminate this for loop?

Answer 1

您可能会作弊：

i = -1;

Answer 2

It's not sooo ridiculous. Some purists consider break as being evil - similar to "mutliple return statements", but not as much as " break with label" or goto . A program with nested loops and some break statements can be rather confusing.

Another possible solution here would be something like this:

private int findInsertionIndex()
{
    for(int i = LOWEST_ROW_INDEX; i >= 0; i--)
    {
        if(gb[i][rChoice].equals(". "))
        {
            return i;
        }
    }
    return -1;
}

// Use
int insertionIndex = findInsertionIndex();
if (insertionIndex != -1)
{
    gb[insertionIndex][rChoice] = "r ";
}

(Yes, I know that I traded a break against a method with "multiple returns". Sometimes it's all about playing the game. I think the code snippet already shows some practices that one could consider as worse than a break . For example, odd variable names, global variables and a 2D array of Strings...)

Answer 3

Convert it to while

int i = LOWEST_ROW_INDEX;
while(!gb[i][rChoice].equals(". ") && i >=0 ){
  i--;
}
if (i >= 0){
  gb[i][rChoice] = "r ";
}