java - Initialize certain size to an array -

hi i'm trying create array prefixed size(eg,size of 10) in main , add items(eg, 3 items) in array, make array have 7 unused spaces, later on, want write method trim unused size.

but how can first create array fixed size because constructor won't allow operation below.

*bag<string> names = new bag<string>(**10**);*   public class bag<t extends comparable<t>> implements iterable<t> {   private int max_items = 10; // initial array size   private int size;   private t[] data;    public bag( ) {       data = (t []) new comparable[max_items];       size = 0;       }    public static void main(string[ ] args) {       bag<string> names = new bag<string>();         names.add("seattle");         names.add("chicago");         names.add("new york");          system.out.println(names.size());         (string name : names)             system.out.println(name);          names.trimtosize();         system.out.println(names.size());   } } 

you can create following method in utility class , use every time need it:

public static <t> t[] newarrayof(t[] t, int len){         return (t[]) array.newinstance(t.getclass().getcomponenttype(), len);     }