Darksiders

I need to keep myself away from Japanese on the dark side, such as typically 2ch users, or those who really use its slangs or behave as written there. Generally speaking those who live, speak, and observe only in the Net or video games, i.e. social myopia.
Not want to keep away because of narrowing the world, but should do so.

When they're in tough or bad situation, they tend to say, "Then I will do bad things, to someone or to anyone." or "I will shut myself up in my room (possibly metaphorically)."
When they're criticized by someone, they say, "Do you think I'm such stupid as you say?!" It seems they hate 'stupid'.

For they very much lower moral and morale, then I have to keep them as much extra effort, which is unnecessary and wasteful.
As my declaration for working well on business.

HTML5 input date validation

HTML5 has <input type="date"> and browsers which support it show their own date picker calender.
And what if you input invalid date, e.g. 2016/2/30?
W3C HTML5 spec says

The value sanitization algorithm is as follows: If the value of the element is not a valid date string, then set it to the empty string instead.

So you never get an original invalid date value.

How can you handle it?


You only know if a value is invalid or not with...

1. input.validity.badInput
2. input.validity.valid
3. input.validationMessage

Further details, please see this: http://stackoverflow.com/questions/13278016/get-input-value-from-html5-inputtype-date-in-chrome/24081375#24081375

git svn Commands State Diagram

 Some people haven't yet used Git because they've already utilized Subversion in their projects or they've never used Git and been afraid of it.
 Even in that case you can however use Git within your local PC, which way is to commit your files to Subversion from your local Git environment. Thus you'll get the situation other people use Subversion only but you use Git, which is anyway better than vanilla Subversion.
 How to use Git with Subversion? That's by a git command, git svn.
 I created the state diagram of git and git svn commands because I can find git diagram but hardly ever git svn one.
 Here you are:

Legend:
 ">..." on an edge: git commands

Red edges: a flow to commit to Subversion repository

Blue edges: a flow to update from Subversion repository

 Can I help you, who are irritated against hackneyed Subversion or trying to use Git?

Hibernate Session Scope Strategy 1/3 Theory

This series of article is about handling synchronization of domain object life cycle by Hibernate.
Some parts of it are simplified for the convenience of the blog.

Those are the strategies how to handle scopes of Hibernate Session: we may say Session Scope Strategy, Session Holding Strategy, Open Session Strategy, etc.
This explanation is based by Hibernate + Spring Frameworks.


A Hibernate Session with Spring Framework closes at the same time a transaction session syncs with finished. And the synchronization of an entity (domain object) with SessionFactory comes to be broken(*1).

  *1 For a sync of an entity with SessionFactory to come to be broken is called as to 'detach.' Such a object is called as an 'detached object.'


When using Lazy Loading (this is the default setting of Hibernate), after a transaction finished, you execute a getter method of an entity, a LazyInitializationException occurs:

org.hibernate.LazyInitializationException: could not initialize proxy - no Session
    at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:86)
    at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:140)
    at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:190)
    ...

Leaving it be, it comes to be harmful.

1. You cannot get a property on demand(i.e. you cannot use Lazy Loading on view rendering).
2. When you use a domain object between several screens, you have to get a domain object by event even if that domain objects are the same(i.e. Optimistic locking between screen events comes to be manual).

If your system is distributed and business process and view process are divided by a protocol(e.g. SOAP), you have to live with it by beforehand executing getter methods, or eagar-fetching properties. But if your system is in one physical server, it is preferable to resolve it.

That is to say, if you can make Hibernate Session open while you want to get properties of domain objects, this problem will be resolved. Which means you take around Hibernate Session as open.

There are two strategies to take around Hibernate Session as open.

1. Open Session In View (OSIV)
2. Flow Managed Persistence (FMP)

1. OSIV is the design strategy to make Session open from one request-to-response. This can be set without any other implementation if you use OpenSessionInViewFilter which Spring Framework provides. This is correspond to harmful 1.
2. FMP is that to make Session open within the scope you set as you want between screens. This can be set without any other implementation if you use Spring Web Flow(SWF). you can make Session open by the scope which SWF defines. This is correspond to harmful 2.

To wrap up, the following:

Hibernate Session Scope Strategy Patterns

Strategy Pattern	Scope	Problem to resolve	Means
Open Session In View (OSIV)	1 request (Session-per-request)	errors related to LazyLoading occur on rendering a view	SessionInViewFilter class which Spring Framework provides
Flow Managed Persistent(FMP)	1 conversation(Session-per-conversation)	You have to synchronize manually a domain object on a process between screens/buttons(long Unit of Work)(e.g. session.reflesh())	Spring Web Flow(SWF)

If you don't use SWF, you should implement FMP manually.
Otherwise you use JBoss Seam on EJB Server, you can do as well as FMP.

Then when you use SWF, you'd better use FMP.

How to set them actually is the next.

T.B.C.