validation - Where should I validate arguments? Factory Pattern, Java -


suppose have abstract class abstract builder, both of inherited 3 separate subclasses: 

public abstract class role {      protected string name;     protected int propertya;     protected int propertyb;       protected abstract static class rolebuilder<t extends role, b extends rolebuilder<t,b>> {           protected t role;         protected b rolebuilder;          protected abstract t getrole();         protected abstract b thisbuilder();          protected rolebuilder(hero h) {              role = getrole();             rolebuilder = thisbuilder();              role.name = h.name;             role.propertya = h.propertya;              role.propertyb = h.propertyb;          }          public t build() {             return role;         }      } }   public class healer extends role {      int propertyc;      public healer() {      }      public static final class healerbuilder extends role.rolebuilder<healer, healerbuilder> {          @override protected healer getrole() {             return new healer();         }          @override protected healerbuilder thisbuilder() {             return this;         }          public healerbuilder(hero h) {             super(h);         }          public healerbuilder setpropertyc(int i) {             role.propertyc = i;             return rolebuilder;         }       } }

i instantiate healer class (and other 2 subclasses) using enums methods within enums, so: 

public enum roletypes {     bruiser{     ...     },     damage_dealer {     ...     },     healer {          public healer getrole(hero h) {             return new healer.healerbuilder(h)                      .setpropertyc(h.getc);                     .build();         }      };      abstract role getrole(hero h); }

where should validating arguments creation of these objects?

  • within abstract class constructor (should validate hero object properties, or can assume object "safe" if properties validated on creation?) , subclass builder methods?

  • within enum methods?

  • within factory method calls roletype.getrole(h), used rest of application create objects of type role?


Comments

Post a Comment

Popular posts from this blog

android - InAppBilling registering BroadcastReceiver in AndroidManifest -

i'm implementing inapp billing in android app. works well, however, i'm trying decouple broadcast receiver activity manifest. suggestion in android's trivialdrive sample: // important: dynamically register broadcast messages updated purchases. // register receiver here instead of <receiver> in manifest // because call getpurchases() @ startup, therefore can ignore // broadcasts sent while app isn't running. // note: registering listener in activity bad idea, done here // because sample. regardless, receiver must registered after // iabhelper setup, before first call getpurchases(). currently there's class extends broadcastreceiver : public class iabbroadcastreceiver extends broadcastreceiver { /** * intent action receiver should filter for. */ public static final string action = "com.android.vending.billing.purchases_updated"; private final iabbroadcastlistener mlistener; public iabbroadcastreceiver(iabbroadcastlistener listener) { m...
Read more

python Tkinter Capturing keyboard events save as one single string -

is possible store keyboard events 1 string? code below stores 1 char , prints it. card reader or bar code reader, contains collection of character/ string not 1 character @ time. goal save char pressed text variable. from tkinter import * root = tk() def key(event): text= event.char text+= event.char print ("pressed", text) def callback(event): frame.focus_set() print ("clicked at", event.x, event.y) frame = frame(root, width=100, height=100) frame.bind("<key>", key) frame.bind("<button-1>", callback) frame.pack() root.mainloop() currently, creating text variable , everytime key() function gets called, , text stores last character typed. you can define text module level variable , , use module level text inside key function - text = '' def key(event): global text text+= event.char print("pressed", text)
Read more

sql server - Why does Linq-to-SQL add unnecessary COUNT()? -

here tables: create table customer ( cid int primary key, name varchar(32) ) create table ord ( oid int primary key, cid int foreign key references customer, address varchar(20) ) here's linq-to-sql statement: var aaa = c in db.customer select new { c, o = c.ord.tolist() }; and here's inexplicable query generated linq-to-sql: select [t0].[cid] [cid], [t0].[name] [name], [t1].[oid] [oid], [t1].[cid] [cid2], [t1].[address] [address], (select count(*) [dbo].[ord] [t2] [t2].[cid] = [t0].[cid]) [value] [dbo].[customer] [t0] left outer join [dbo].[ord] [t1] on [t1].[cid] = [t0].[cid] order [t0].[cid], [t1].[oid] i want understand how rid of count(*) part. it's entirely uncalled for! linq needs count(*) in order determine number of entries returned o = c.ord.tolist() .
Read more