Java object sorting

1. Implement the comparable interface of the class to be compared

 
Public class menupage implements comparable <menupage> {private string text; private string seq; // The Order of menus on the page is 0, 1, 2 .... @ Overridepublic int compareto (menupage O) {// return integer. valueof (this. attribute1)-integer. valueof (O. attribute1); int result = integer. valueof (this. SEQ ). compareto (integer. valueof (O. SEQ); If (result = 0) return 1; elsereturn result ;}
 

Use treeset (the compareable interface class will be automatically called) for comparison during addition.

 
Set <menupage> List = new treeset <menupage> (); list. add (page1); list. add (page2); list. add (page3); list. add (page4 );
 

2. Use manual sorting (compareable is not required when defining classes)

List <menupage> List = new arraylist <menupage> (); list. add (page1); list. add (page2); list. add (page3); list. add (page4); collections. sort (list, new comparator <menupage> () {@ overridepublic int compare (menupage O1, menupage O2) {return integer. valueof (o1.getseq ()). compareto (integer. valueof (o2.getseq ()));}});