Convert an infix expression to an array of numbers and operators. For example: "33+1 *(5+2)/ 7 " should convert to an array with each digit and operator as an individual item. There can or cannot be space between numbers and operators. The string should convert to array = [33,+,1,*,(,5,+,2,),/,7] . There is no space 33 and 1, but there is space between 1 and * , / and 7. Also 33 should be one item and not two items like 3 and 3 in the array.

The code should be in Java.