Unmodifiable List in java -


i'm trying set list unmodifiable.

in code, have method returns list.

this list shouldn't modified, don't want catch exception returned unmodifiablelist.

private list<t> listereferenceselectall = null; list<t> olisteret = new arraylist<t>(); olisteret = listereferenceselectall; return new arraylist<t>(olisteret);

it existing code , have transform return unmodifiable list, if "add" method has been called, no exception has caught.

first have create class implements list override "add" method log exception , not catch it.

but don't know how correctly instantiate it...

if absolutely must this, try follow contract specified java.util.list in list creating.

your code 

public class unmodifiablearraylist<e>  extends arraylist<e> {      public unmodifiablearraylist(collection<? extends e> c) {         super(c);     }      public boolean add(int index) {         return false;//returning false element cannot added      }      public boolean addall(collection<? extends e> c) {         return false;//returning false element cannot added      }      public e remove(int index) {         return null;//returning null element cannot removed     } }

add more methods need on same lines. ensure constructors , methods might used modify in code overriden, ensure list unmodifiable.

using collections api cleaner , better way it, use way if using collections.unmodifiablelist not satisfy need.

and keep in mind nightmare while debugging log as possible.


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