如何在Java (Eclipse)中对二维Char数组中的字符串进行对角检查

Question

我从用户那里获得一个单词列表作为输入，并将它们的输入存储在一个String[]数组中。然后，我创建了一个名为letterGrid的字符数组，其中填充了随机字母和用户提供的单词。然后，用户必须输入他们想要在控制台屏幕上显示letterGrid时查找的单词。然后，程序将检查输入的单词是否水平、垂直或对角出现，并打印出红色、橙色、黄色、绿色、蓝色、紫色、彩虹, and颜色。下面是输出网格：

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正如您所看到的，当我输入黄色(长度为6个字母)时，程序会输出单词的位置，但随后会出现越界错误。

编辑过的代码

应@Igor Khvostenkov的要求，下面是代码的其余部分：

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 	private String word; // This variable will be the user`s input when they chose to search for a word they have entered
    private int rowLocation; // This variable will represent the row number in which the word is at
    private int colLocation; // This variable will represent the column number in which the word is at
 
 // Create a method to compare the user`s word to the elements in the letter grid
 public void compare (String word) {
    	
        for (int row = 0; row < letterGrid.length - 1; row++) {
        	
            for (int col = 0; col < letterGrid[row].length - 1; col++) {
            	
                if (letterGrid[row][col] == word.charAt(0)) {

                    rowLocation = row;
                    colLocation = col;

                    wordContains(); // Call on method to see if the word entered by the user appears horizontally, vertically, or diagonally
                    
                }//end of if
                
            }//end of inner for loop
            
        }//end of outer for loop
        
    }//end of compare(word)
    
    // Create a method that will check the direction of the user`s word input

    public void wordContains() {
    	
        checkHorizontal(); // Checking if the word appears horizontally
        checkVertical(); // Checking id the word appears vertically
        checkDiagonal(); // Checking if the word appears diagonally
        
    }//end of wordContains()
    
    // Create a method to check if the user`s word appears HORIZONTALLY in the letter grid

    public void checkHorizontal() {
    	
        for (int i = 1; i < (word.length()); i++) {
        	
            if (colLocation + i > letterGrid[0].length - 1) {
            	
                return;
                
            } else if(letterGrid[rowLocation][colLocation + i] != word.charAt(i)) {
            	
               return;
               
            }//end of if..else if
            
        }//end of for loop
        
        System.out.println(word + " found horizontally at row " + rowLocation + " and column " + colLocation); // Word found!!
        System.out.println();

        return;

    }//end of checkHorizontal()

    // Create a method to check if the user`s word appears VERTICALLY in the letter grid
    
    public void checkVertical() {
    
        for (int i = 1; i < (word.length()); i++) {
        
            if (rowLocation + i > letterGrid.length - 1 && colLocation + i > letterGrid[0].length) {
                
            	return;
            	
            } else if (letterGrid[rowLocation + i][colLocation] != word.charAt(i)) {
            	
            	return;
            	
            }//end of if..else if
            
        }//end of for loop
        
        System.out.println(word + " found vertically at row " + rowLocation + " and column " + colLocation); // Word found!!
        System.out.println();          
        
    }//end of checkVertical()
    
    // Create a method to check if the user`s word appears DIAGONALLY in the letter grid

    public void checkDiagonal() {
    	
        for (int i = 1; i < (word.length()); i++) {
        	
            if (colLocation + i > letterGrid[0].length - 1 || rowLocation + i > letterGrid.length - 1) {
            	
                return;
                
            } else if (letterGrid[rowLocation + i][colLocation + i] != word.charAt(i)) {
            	
                return;
                
            }//end of if..else if
            
        }//end of for loop
        
        System.out.println(word + " found diagonally at row " + rowLocation + " and column " + colLocation); // Word found!!
        System.out.println("");
        
    }//end of checkDiagonal()

​

I cant seem to know why this is happening, and how I can fix this. I am not that familiar with ArrayIndexOutofBounds Exceptions as I barely go through them, but recently I have been and I我一直在努力理解这个问题，并寻找帮助我解决它的方法。

Answer 1

代码中的问题存在于checkVertical()中的if条件中，即行和列可以是第一行或最后一列，但您应该检查行或列。您的黄色示例失败，因为首先代码在第一行和第二列中查找Y，然后继续扫描，最后，它在最后一行中查找Y，并检查跳过的rowLocation + i > letterGrid.length - 1 && colLocation + i > letterGrid[0].length，然后调用将该行加1的else，结果是数组越界。这应该是可行的：

 public void checkVertical() {

        for (int i = 1; i < (word.length()); i++) {

            if (rowLocation + i > letterGrid.length - 1 || colLocation + i > letterGrid[0].length) {

                return;

            } else if (letterGrid[rowLocation + i][colLocation] != word.charAt(i)) {

                return;

            }//end of if..else if

        }//end of for loop

        System.out.println(word + " found vertically at row " + rowLocation + " and column " + colLocation); // Word found!!
        System.out.println();

    }//end of checkVertical()