Java二维数组循环触发ArrayIndexOutOfBoundsException的解决方法

Hey, let's break down why you're getting that ArrayIndexOutOfBoundsException and fix it right away!

First off, the issue is a tiny but critical typo in your nested for loop—you accidentally used i++ instead of j++ in the inner loop!

Why this breaks things: #

• Your outer loop uses i to iterate over the rows of your 10x10 array, starting at 0 and stopping when i hits 10 (since array indices go from 0 to 9 for a length-10 array).
• But in the inner loop, you meant to increment j to iterate over each column in the current row. Instead, you're incrementing i here. This makes i skyrocket past the array's maximum index (9) in no time—by the time i hits 10, trying to access gametable[i][j] is asking for an index that doesn't exist, hence the exception.

Here's the corrected code: #

int x=10,y=10; 
char[][] gametable=new char[x][y]; 
for(int i=0;i<gametable.length;i++) { 
    for(int j=0;j<gametable[i].length;j++) { // Changed i++ to j++ here
        gametable[i][j]='.'; 
        System.out.print(gametable[i][j]); 
    } 
    System.out.println(); // Swapped out println(i) for a plain newline to format the grid properly
}

A quick extra tip: #

I also swapped System.out.println(i) with a plain System.out.println()—your original code would print the row index after each line of dots, which I assume wasn't your goal. This change will output a clean 10x10 grid of dots, each row on its own line.

Nested loops are tricky for exactly these little mix-ups—always double-check that your loop variable matches the increment!

内容的提问来源于stack exchange，提问作者Hui HiuShi