This is not only true of perl and Java. In my C++ class I learned many, easily 20+ lines of code, difficult ways to create unlimited arrays. Once I looked at the standard headers included with C++, this was 4 years ago, I noticed vector.

#include <vector>
#include <iostream>

std::vector<char> array;
char c = 0;

while(c != 'X' || c != 'x')
{
  //enter something or exit to quit
  std::cin>>c;
  array.push_back(c); //remind you of anything ;)
}
std::cout<<array.size()<<std::endl;
/* btw., the way I learned to get an arrays length was to create a sec
+ond int array as a counter*/
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As for why the One Way, or more approapriately Best Way is ignored, that's a good question