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kuni katsuya

Lean service architectures with Java EE 6 - JavaWorld - 0 views

www.javaworld.com/...-04-lean-soa-with-javaee6.html

javaee6 lean service architecture DAO

shared by kuni katsuya on 30 Jul 12 - No Cached
  • DAOs aren't dead, but they cannot be considered as a general best practice any more. They should be created in a bottom-up, rather than a top-down, fashion. If you discover data-access code duplication in your service layer, just factor it out to a dedicated DAO and reuse it. Otherwise it is just fine to delegate to an EntityManager from a service. The enforcement of an empty DAO layer is even more harmful, because it requires you to write dumb code for even simple use cases. The more code is produced, the more time you must spend to write tests and to maintain it.
  • With JDK 1.5 and the advent of generics, it is possible to build and deploy a generic, convenient, and typesafe DAO once and reuse it from variety of services
  • kuni katsuya on 30 Jul 12
     
    DAOs aren't dead, but they cannot be considered as a general best practice any more. They should be created in a bottom-up, rather than a top-down, fashion. If you discover data-access code duplication in your service layer, just factor it out to a dedicated DAO and reuse it. Otherwise it is just fine to delegate to an EntityManager from a service. The enforcement of an empty DAO layer is even more harmful, because it requires you to write dumb code for even simple use cases. The more code is produced, the more time you must spend to write tests and to maintain it.
kuni katsuya

Generic CRUD Service aka DAO - EJB 3.1/0 Code - Only If You Really Needed : Adam Bien's... - 0 views

www.adam-bien.com/...generic_crud_service_aka_dao

javaee6 patterns GenericCrudService DAO ejb3.1

shared by kuni katsuya on 12 Oct 12 - Cached
  • Generic CRUD Service
  • The term Data Access Object (DAO)
  • is actually wrong
    • kuni katsuya
      kuni katsuya on 12 Oct 12
       
      this is one reason i hate using the term 'dao' in our ee6 project
  • ...7 more annotations...
  • easy with generics
  • create
  • find(
  • update(
  • delete(
  • CrudService
  • @TransactionAttribute(TransactionAttributeType.MANDATORY)
kuni katsuya

Selling Weld and EE6 | Weld | JBoss Community - 0 views

community.jboss.org/...656586

javaee6 weld Spring GavinKing

shared by kuni katsuya on 28 Sep 12 - No Cached
  • regarding the issue of selling Weld and EE6 to developers/shops....
  • How bout a JdbcTemplate Spring equivalent in the case of projects using legacy db schemas
  • portable extension to Weld
  • ...32 more annotations...
  • William Drai
  • Honestly I don't see any value in switching to CDI if it is
  • to reproduce the same awful patterns
  • please not this Dao/Template mess
  • Gavin King
  • Their template pattern is a solution in search of a problem
    • kuni katsuya
      kuni katsuya on 28 Sep 12
       
      gold! :)
  • to reproduce the same awful patterns
  • please not this Dao/Template mess
  • Because, of course, there are no other well-known patterns for dealing with boiler-plate cleanup code and connection leaks.
  • This is exactly the kind of
  • brain-damage that Spring does to people!
    • kuni katsuya
      kuni katsuya on 28 Sep 12
       
      platinum!!!
  • It gives people a
  • half-assed solution
  • and somehow shuts down their brains so they
  • stop asking themselves how this solution could be improved upon
  • It's a very impressive magic trick, and I wish I knew how to do it myself. But then, I'm just not like that. I'm always trying to poke holes in things - whether they were Invented Here or Not.
  • but that might be too high-level for your taste. Their are other, less-abstract options.
  • exception handling, this is one area where Spring does a good job: "The Spring Framework's handling of SQLException is one of its most useful features in terms of enabling easier JDBC development and maintenance. The Spring Framework provides JDBC support that abstracts SQLException and provides a DAO-friendly, unchecked exception hierarchy."
  • Utter nonsense and dishonest false advertising
  • Automatic connection closing (and other boiler-plate code) is obviously a hard requirement to be handled by the fwk.
  • Pffffff. It's a trivial requirement which I can solve in my framework with two lines of code in a @Disposes method. Did you see any connection handling in the code above?
  • I mean, seriously guys. The Spring stuff is trivial and not even very elegant. I guess it's easier for me to see that, since I spent half my career thinking about data access and designing data access APIs. But even so...
  • I don't understand. You hate the ability to write typesafw SQL that much?
  • Gavin King
  • Methods with long argument lists are a code smell.
  • It's something Spring copied from Hibernate 1.x, back in the days before varargs
  • It's something we removed in Hibernate2 and JPA.
  • there are a bunch of people
  • who don't want to use JPA.
  • They don't understand, or see the value of, using managed objects to represent their persistent data.
  • Um. Why? Why would that be a bad thing? I imagine that any app with 1000 queries has tens of thousands of classes already. What's the problem? Why is defining a class worse than writing a method?
  • Are you working from some totally bizarre metric where you measure code quality by number of classes?
kuni katsuya

Auditing Entities With JPA Events | Andy Gibson - 0 views

www.andygibson.net/...iting-entities-with-jpa-events

jpa events auditing

shared by kuni katsuya on 23 May 12 - No Cached
  • Auditing Entities With JPA Events
  • An alternative is if you are using a generic DAO class to handle entity persistence is to put the enhanced populateTimestamp method on there and call it prior to inserting or updating the entity in the DAO
kuni katsuya

Dependency injection discourages object-oriented programming? @ Blog of Adam Warski - 0 views

www.warski.org/...es-object-oriented-programming

java javaee6 CDI CdiDependencyInjection OO Object-Oriented procedural DI DependencyInjection

shared by kuni katsuya on 12 Dec 12 - No Cached
  • Dependency injection discourages object-oriented programming?
  • if you’re using DI, and you have an X entity, do you have an XService or XManager with lots of method where X is the first argument?
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      evidence of the anti-pattern of procedural design in a java ee6 cdi application
  • previous way is more procedural
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      ie. ProductService.ship(Product,Customer)
  • ...12 more annotations...
  • service/manager is a set of procedures you can run, where the execution takes a product and a customer as arguments
  • better
  • OO approach
  • not saying that achieving the above is not possible with a DI framework
  • only that DI
  • encourages the ProductService approach
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      well, dependency injection, but moreover, the soa approach to service design tends to force otherwise intelligent software engineers into doing procedural design the services just end up being bags of method calls that implement any type of behavior, with the domain objects or entity beans being reduced to mere data structures with little responsibility or behavior beyond persistence. (which, in this anti-pattern, is typically mostly provided by the repository or dao class! ie. domain object crud)
  • it’s just easier
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      ... if you just blindly follow the anti-pattern, of course  ;)
  • many benefits
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      with the procedural approach, you also cannot implement polymorphic behavior, for instance
  • builder
  • fluent interface
  • it’s not for small projects
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      fuckwhat? small or big matters not. if di is applied poorly, regardless of project size, it's an anti-pattern! disregard these comments!
  • problems with DI frameworks:
    • kuni katsuya
      kuni katsuya on 12 Dec 12
       
      not sure i agree with these points, but will refuse in a later sticky note
kuni katsuya

A proper way for JPA entities instantiation « Paul Szulc's Blog - 0 views

paulszulc.wordpress.com/...for-jpa-entities-instantiation

database jpa EntityBeans BuilderPattern

shared by kuni katsuya on 03 Oct 12 - No Cached
  • A proper way for JPA entities instantiation
  • creating the entities I would like to focus in this post
  • JPA2.0 entities
  • ...31 more annotations...
  • UserService
  • UserDao
  • FacebookWS
  • User u
  • UserService uses UserDAO and FacebookWS
  • but don’t know how those dependencies are instantiated
  • And you shouldn’t really care, all that is important is that UserService depends on dao and webservice object.
  • BDD template given-when-then) tests are easy to read
  • @Entity
  • public class User
  • calling new User(“someName”,”somePassowrd”, “someOtherName”, “someOtherPassword”) becomes hardly readable and maintainable
  • code duplication
  • Maintaining this code would turn into a nightmare in no time
  • running the code above will throw an exception by the JPA provider,
  • since not-nullable password field was never set.
  • Joshua Blooch gives fine example of builder pattern.
  • Instead of making the desired object directly, the client calls a constructor (or static factory) with all of the required parameters and gets a builder object. Then the client calls setter-like methods on the builder object to set each optional parameter of interest. Finally, the client calls a parameterless build method to generate the object, which is immutable. The builder is a static member class of the class it builds.
  • Coffee
  • public static class Builder
  • Builder(CoffeeType type, int cupSize)
  • Builder withMilk()
  • Coffee build()
  • Coffee(this)
  • private Coffee(Builder builder)
  • Coffee coffee = new Coffee.Builder(CoffeeType.Expresso, 3).withMilk().build();2}
  • especially if most of those parameters are optional.
  • For all entity attributes I create private fields
  • those that are obligatory become parameters for the public constructor
  • parameter-less constructor, I create one, but I give him
  • protected access level
  • protected
kuni katsuya

Session Management | Apache Shiro - 1 views

shiro.apache.org/session-management.html

ApacheShiro SessionManagement SessionClustering clustering

shared by kuni katsuya on 08 Nov 12 - No Cached
  • Session Clustering
  • can cluster Subject sessions natively and never need to worry again about how to cluster sessions based on your container environment
  • if you configure a cluster-capable SessionDAO, the DAO can interact with a clustering mechanism and Shiro's SessionManager never needs to know about clustering concerns
  • ...8 more annotations...
  • Therefore enabling Session clustering in Shiro is
  • as simple as configuring Shiro to use a distributed cache
  • Ehcache+TerraCotta
  • When Shiro initializes the
  • SessionDAO implements the CacheManagerAware interface
  • call the
  • setCacheManager
  • Ehcache + Terracotta
kuni katsuya

Article Series: Migrating Spring Applications to Java EE 6 - Part 3 | How to JBoss - 0 views

howtojboss.com/...rom-spring-to-java-ee-6-part-3

spring javaee6 migration

shared by kuni katsuya on 02 Jul 12 - No Cached
  • Stateless Session Bean is transactional by default
  • In this article we will discuss migrating the DAO layer, AOP and JMX
  • Migrating JDBC templates
  • ...3 more annotations...
  • In general, JDBC Templates are a poor solution. They don’t have enough abstraction to work on different databases because you use plain SQL in queries. There is also no real ORM mapping which results in quite a lot of boilerplate code
  • SimpleJdbcTemplate(ds)
  • @InterceptorBinding
  • kuni katsuya on 02 Jul 12
     
    Stateless Session Bean is transactional by default.
kuni katsuya

Realm (Apache Shiro :: Core 1.1.0 API) - 0 views

127.0.0.1/...Realm.html

security ApacheShiro Realm authentication authorization user Role Permission

shared by kuni katsuya on 03 Sep 12 - No Cached
  • Interface Realm
  • AuthenticatingRealm
  • AuthorizingRealm
  • ...7 more annotations...
  • JdbcRealm
  • A Realm is a security component that can access application-specific security entities such as users, roles, and permissions to determine authentication and authorization operations
  • security-specific DAOs
  • If for some reason you don't want your Realm implementation to perform authentication duties, you should override the supports(org.apache.shiro.authc.AuthenticationToken) method to always return false
  • does not require you to implement or extend any User, Group or Role interfaces or classes
  • Shiro tries to maintain a non-intrusive development philosophy
  • Most users will not implement the Realm interface directly, but will extend one of the subclasses, AuthenticatingRealm or AuthorizingRealm, greatly reducing the effort requird to implement a Realm from scratch
kuni katsuya

Lean service architectures with Java EE 6 - JavaWorld - 0 views

www.javaworld.com/...-04-lean-soa-with-javaee6.html

javaee6 lean service architecture DAO EntityControlBoundary ECB

shared by kuni katsuya on 30 Jul 12 - No Cached
  • Entity-Control-Boundary (ECB) architectural pattern matches perfectly with our pattern language
  • domain structure is an Entity, the Control is a service, and the Boundary is realized with a facade
  • In simpler cases the facade and service can collapse, and a service would be realized only as a facade's method in that case
kuni katsuya

Realm | Apache Shiro - 0 views

shiro.apache.org/realm.html

Shiro Realm

shared by kuni katsuya on 09 Aug 12 - No Cached
  • A Realm is a component that can access application-specific security data such as users, roles, and permissions. The Realm translates this application-specific data into a format that Shiro understands so Shiro can in turn provide a single easy-to-understand Subject programming API no matter how many data sources exist or how application-specific your data might be.
  • A Realm is essentially a security-specific DAO
kuni katsuya

Application Security With Apache Shiro - 0 views

www.infoq.com/...apache-shiro

security ApacheShiro

shared by kuni katsuya on 08 Aug 12 - No Cached
  • previously known as the JSecurity project
  • The word Subject is a security term that basically means "the currently executing user"
  • Core Concepts: Subject, SecurityManager, and Realms
  • ...12 more annotations...
  • Subject
  • 'Subject' can mean a human being, but also a 3rd party process, daemon account, or anything similar. It simply means 'the thing that is currently interacting with the software'
  • Subject currentUser = SecurityUtils.getSubject();
  • SecurityManager
  • SecurityManager manages security operations for all users
  • Realms
  • Realm acts as the ‘bridge’ or ‘connector’ between Shiro and your application’s security data. That is, when it comes time to actually interact with security-related data like user accounts to perform authentication (login) and authorization (access control), Shiro looks up many of these things from one or more Realms configured for an application.
  • Realm is essentially a security-specific DAO
  • Shiro provides out-of-the-box Realms to connect to a number of security data sources (aka directories) such as LDAP, relational databases (JDBC), text configuration sources like INI and properties files, and more
  • Authorization
  • A permission is a raw statement of functionality, for example ‘open a door’, ‘create a blog entry’, ‘delete the ‘jsmith’ user’, etc. By having permissions reflect your application’s raw functionality, you only need to change permission checks when you change your application’s functionality. In turn, you can assign permissions to roles or to users as necessary at runtime.
  • “Run As” support for assuming the identity of another Subject
kuni katsuya

Architecture | Apache Shiro - 0 views

shiro.apache.org/architecture.html

apache shiro architecture

shared by kuni katsuya on 15 Aug 12 - No Cached
  • Realm is essentially a security-specific DAO
  • 3 primary concepts:
  • Subject
  • ...51 more annotations...
  • SecurityManager
  • Realms
  • High-Level Overview
  • Subject
  • essentially a security specific 'view' of the the currently executing user
  • Subject
  • instances are all bound to (and require) a
  • SecurityManager
  • When you interact with a Subject, those interactions translate to subject-specific interactions with the SecurityManager
  • SecurityManager
  • 'umbrella’ object that coordinates its internal security components that together form an object graph
  • Realms
  • ‘connector’ between Shiro and your
  • application’s security data
  • Shiro looks up many of these things from one or more Realms configured for an application
  • Subject
  • SecurityManager
  • Authenticator
  • Authorizer
  • component responsible determining users' access control in the application
  • if a user is allowed to do something or not
  • SessionManager
  • knows how to create and manage user
  • Session
  • lifecycles
  • Shiro has the ability to natively manage user Sessions in any environment, even if there is no Web/Servlet or EJB container available
  • Shiro will use
  • an existing session mechanism
  • if available, (e.g. Servlet Container)
  • if there isn't one, such as in a standalone application or non-web environment, it will use its
  • built-in enterprise session management
  • SessionDAO
  • exists to allow any datasource to be used to
  • persist sessions
  • SessionDAO
  • performs Session persistence (CRUD) operations on behalf of the SessionManager
  • allows any data store to be plugged in to the Session Management infrastructure
  • CacheManager
  • creates and manages Cache instance lifecycles used by other Shiro components
  • improve performance while using these data source
  • Cryptography
  • Realms
  • ‘connector’ between Shiro and your application’s security data
  • Realms
  • Realms
  • Realms
  • ‘connector’ between Shiro and your application’s security data
  • ‘connector’ between Shiro and your application’s security data
  • ‘connector’ between Shiro and your application’s security data
  • ‘connector’ between Shiro and your application’s security data
  • ‘connector’ between Shiro and your application’s security data
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