Java 18-11 collections used in ArrayList collection

Collections can sort the elements that store the basic wrapper class for ArrayList and store custom objects?
　　　Custom objects to sort by writing their own comparators

1  packagecn.itcast_02;2 3 Importjava.util.ArrayList;4 Importjava.util.Collections;5 Importjava.util.Comparator;6 Importjava.util.List;7  public classCollectionsdemo {8      public Static voidmain (string[] Args) {9         //to Create a Collection objectTenlist<student> list =NewArraylist<student>(); one  a         //Create student Objects -Student S1 =NewStudent ("brigitte", 27); -Student s2 =NewStudent ("wind qing", 30); theStudent s3 =NewStudent ("lynn qu", 28); -Student S4 =NewStudent ("Wu Xin", 29); -Student S5 =NewStudent ("brigitte", 27); -  +         //Adding an Element object - List.add (s1); + List.add (s2); a List.add (s3); at List.add (s4); - List.add (s5); -  -         //Sort -         //Natural Sort -         //Collections.sort (list); in         //Comparator Sort -         //If you have both a natural sort and a comparator sort, the comparator is sorted primarily toCollections.sort (list,NewComparator<student>() { + @Override -              public intCompare (Student s1, Student s2) { the                 intnum = S2.getage ()-s1.getage (); *                 intnum2 = num = = 0?s1.getname (). compareTo (s2.getname ()) $ : num;Panax Notoginseng                 returnnum2; -             } the         }); +  a         //iterating through the collection the          for(Student S:list) { +System.out.println (s.getname () + "---" +s.getage ()); -         } $     } $}

Java 18-11 collections used in ArrayList collection