Why is this error thrown

Question

im in the middle of a project for my cs class and im running up on this error and i dont know why.
name = temp.toString();
temp = new StringBuffer(10);
check = (char)infile.read();
while ( check != '\n' )
temp.append(check);
check = (char)infile.read();
} //end while
name = temp.toString();
weight = Integer.parseInt( name );
lift.setPerson(weight, name, counter);
counter++;
check = (char)infile.read();
} //end while
infile.close();
it is giving me a number format exception on the parse int, the error message says the string contains "30" so i dont know why it is giving me problems.

Answer 1

ive got another one now. the very next line
lift.setPerson( weight, name, counter);
is giveing me Null pointer exception(in people.elevator)
i instantiated the elevator object(lift) and the constructor makes an array of another object named People.
private People[] occupants;
private int howMany;
private int totalWeight;
public elevator(int a)
occupants = new People[a];
howMany = 0;
totalWeight = 0;
} //end constructor
public void setPerson(int w, String s, int c)
occupants[c].setPeople( s,w);
} //end setPerson
the set people paramater list is in the right order and people should have been instantiaded with the rest of elevator.