toggle div only when array size is greater than 0

I have a function with a lot of if and else and it looks very messy. I want to know if there is a better way to do this. This is a java function so feel free to suggest ways using try and catch, etc. My first two if statements are checking if an object is null or not. My third if statement is checking if older time is less than newer time OR one of the values is null. If one of the values is null, I want it to return true. It is doing everything correctly right now but it is very messy as my code inside the third if statement is messy as well. Is there a better way to do this? Any help will be appreciated.

My code: (I made the code more like web development for easier understanding)

if (customer != null) 
{
  if (customerDetails != null)
  {
    if ((olderTime == null || newerTime == null) || olderTime.before(newerTime))
    {
      // Some code here
    }
    else
    {
      console.log("Older Time must be before Newer Time");
    }
  }
  else
  {
    console.log("Customer details doesn't exist");
  }
}
else
{
  console.log("Customer doesn't exist")
}