How to split a String into an Array of String in java without using split?

I have to split a given string (eg: "The dog plays in the rain") to create an array of string ({"The","Dog","plays", "in", "the","raine}). I cannot use split or any other predefined method. I tried to go through the array with a loop and to make it create a new substring made of the previous word every time it hit a space but without success...

Thanks in advance :)