This is java code

subList = this.list.subList(0,index);

...

...assuming I have a vectorlist first, then later, initiate a vectorsubList (explaining the meanings of subList and list in code)

int index = 0; //explains where index came from

Char is the name of a previously created class

BigDecimal is the name of the class the vectors are within...

...

What does this mean in C++ code (what does it look like after being converted into c++)?

...

...

...

Also, what is return Integer.parseInt(s);

translated in C++?