二维数组查找 java

public boolean Find(int target, int [][] array) {
        int rows = array.length - 1,cols = array[0].length - 1,firstrows = 0;
        boolean flag = false;
        if(rows<=0 || cols<=0)
            System.out.println("数组为空");
        else {
            while(firstrows <= rows && cols >= 0) {
                if(array[firstrows][cols]>target) 
                    --cols;
                else if(array[firstrows][cols]<target) 
                    ++firstrows;
                else {
                    flag = true;
                    break;
                }
            }
        }
        if(flag==false)
            return false;
        else
            return true;
    }