Java array reverse order

Use the for (int i = 0; i<length; i++) loop to realize the reverse order of the array,

1. When it is judged that i exceeds half of (length-1), stop the for loop

When the first array exceeds 4, stop the for loop

When the second array exceeds 5, stop the for loop

(1) Overall code

 /**
     * 倒序数组
     * @param array
     */
    public Object getOrderArray(Object array){

        //字符串一维数组
        if(array instanceof String[]){
            //数组
            String[] array2 = (String[]) array;
            //数组长度
            int length = array2.length;
            //倒序的数组

            for(int i = 0; i<length; i++){
                //超过数组长度一半结束
                if( i > (length-1) /2){
                    return array2;
                }

                //前一个
                String start = array2[i];
                //相应后一个
                String end = array2[length-1-i];

                array2[i] = end;
                array2[length-1-i] = start;

            }


        }
        else if(array instanceof int[]){    //int一维数组
            //数组
            int[] array2 = (int[]) array;
            //数组长度
            int length = array2.length;
            //倒序的数组

            for(int i = 0; i<length; i++){
                //超过数组长度一半结束
                if( i > (length-1) /2){
                    return array2;
                }

                //前一个
                int start = array2[i];
                //相应后一个
                int end = array2[length-1-i];

                array2[i] = end;
                array2[length-1-i] = start;

            }
        }

        else if(array instanceof int[][]){    //int二维数组
            //数组
            int[][] array2 = (int[][]) array;
            //数组列长度
            int lengthY = array2.length;
            int lengthX = array2[0].length;
            //判断列的奇\偶性
            int oddEven = lengthY%2; // 0为偶数,1为奇数
            //倒序的数组

            for(int i = 0; i<lengthY; i++){
                for(int j = 0; j<lengthX; j++){

                    if(oddEven == 0){
                        //超过数组长度一半结束
                        if( i > (lengthY-1) / 2){
                            return array2;
                        }
                    }
                    else if(oddEven == 1){
                        //超过数组长度一半结束
                        if( i >= (lengthY-1)/2  && j > (lengthX-1) / 2){
                            return array2;
                        }
                    }

                    //前一个
                    int start = array2[i][j];
                    //相应后一个
                    int end = array2[lengthY-1-i][lengthX-1-j];

                    array2[i][j] = end;
                    array2[lengthY-1-i][lengthX-1-j] = start;

                }
            }
        }

        System.out.println("传入数据格式错误!");
        return null;
    }

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Origin blog.csdn.net/weixin_46409629/article/details/129751630