David's Untitled Life

I'm implementing upload feature.Javascript can't manipulate file on client machine for security,so i came to iframe firstlly.But i still wonder GMail and microsoft live mail's solution.I found that there were few discussion in domestic ajax forum.But there are many voerseas components.I found all of them use iframe to solve this problem.

So we still need iframe as a approach on AJAX way.

• Concern A particular issue, concept or area of interest for an application. Examples include transaction management, persistence, logging and security.
• Crosscutting Concern A concern in which the implementation cuts across many classes. These are often difficult to implement and maintain with OOP.
• Aspect The modularization of a crosscutting concern; implemented by gathering and isolating code.
• Join Point A point during the execution of a program or class. In Spring's AOP implementation, a join point is always a method invocation. Other examples include accessing fields, where read or write access occurs on an instance variable, and exception handling.
• Advice An action taken at a particular join point. Different types of advice in Spring include around, before, throws and after returning. Of these, around is the most powerful, as you get the opportunity to do something before and after a method is invoked. The previous TraceInterceptor used around advice by implementing the AOP Alliance's MethodInterceptor.
• Pointcut A set of join points specifying when an advice should fire. Pointcuts often use regular expressions or wildcard syntax.
• Introduction Adds fields or methods to an advised class. Spring allows you to introduce new interfaces to any advised object. For example, you could use an introduction to make any object implement an IsModified interface, to simplify caching.
• Weaving Assembles aspects to create an advised object. This can be done at compile time (this is how AspectJ does it) or at runtime. The Weaving Strategies section later in this chapter discusses in detail the different strategies for weaving (that is, implementing AOP).
• Interceptor An AOP implementation strategy, where a chain of interceptors may exist for a particular join point.
• AOP Proxy An object created by the AOP framework, including advice. In Spring, an AOP proxy will be a JDK dynamic proxy or a CGLIB proxy.
• Target Object An object containing the join point. In frameworks using interception, it's the object instance at the end of an interceptor chain. Also called an advised or proxied object.

Hibernate and Lazy Initialization

Hibernate object relational mapping offers both lazy and non-lazy modes of object initialization. Non-lazy initialization retrieves an object and all of its related objects at load time. This can result in hundreds if not thousands of select statements when retrieving one entity. The problem is compounded when bi-directional relationships are used, often causing entire databases to be loaded during the initial request. Of course one could tediously examine each object relationship and manually remove those most costly, but in the end, we may be losing the ease of use benefit sought in using the ORM tool.

The obvious solution is to employ the lazy loading mechanism provided by hibernate. This initialization strategy only loads an object's one-to-many and many-to-many relationships when these fields are accessed. The scenario is practically transparent to the developer and a minimum amount of database requests are made, resulting in major performance gains. One drawback to this technique is that lazy loading requires the Hibernate session to remain open while the data object is in use. This causes a major problem when trying to abstract the persistence layer via the Data Access Object pattern. In order to fully abstract the persistence mechanism, all database logic, including opening and closing sessions, must not be performed in the application layer. Most often, this logic is concealed behind the DAO implementation classes which implement interface stubs. The quick and dirty solution is to forget the DAO pattern and include database connection logic in the application layer. This works for small applications but in large systems this can prove to be a major design flaw, hindering application extensibility.

I found DFlying's blog page's Tag category today,so i also wanna added this web20 feature to mine.But i didn't know how to link to a new template page(not include).My current theme didn't cotain codes like this.I thought DFlying modify the php codes himself.But i suddenly brought to mind that default theme really had archives category link.So finally i found out the code.By the way,during the period of modification,ERROR occured.Error message indicated that LifeType use SMARTY template lib. :) I found out my smarty manual again.But the guys who wanna customize your theme needn't to do that. I found a good tutorial for you and it's easy to understand for guys who knew nothing about PHP.
Download:LifeType.rar My new theme is cool,right?

POJO used by Hibernate needs to implement hashCode() and equals() method.That's a kind of stuffy work and will be done many many times during development.Some IDEs support automatical generation feature such as IDEA.Eclipse famous plug-in--MyElipse also suppots but it's not free of charge.
I think nearly all JAVAers know Apache Commons open source project.We can use Commons lib to generate hashCode() and equals() method.I wanna tell you that there is also a plugin for Eclipse called Commons4E which help you generate hasCode() and equals().
It also can generate toString() and compareTo() method.That's a smart plugin.Enjoy it.Link

See DFlying's finding:
Yep,No Block Scope concept in JavaScript.Only the global and function Scope.You can use "var" to declare a global variable and use "var" agian to declare a homonymous variable in a function.In the function ,the second one works.But there is no Block scope.
Check the codes below,it's a demo for "NO BLOCK SCOPE"
function test(o) {var i = 0; // i is defined throughout functionif (typeof o == "object") {var j = 0; // j is defined everywhere, not just blockfor(var k = 0; k < 10; k++) { // k is defined everywhere, not just loopdocument.write(k);

}document.write(k); // k is still defined: prints 10}document.write(j); // j is defined, but may not be initialized}

But,You still need to care javascript's FUNCTION SCOPE.Also see code snippet:
var scope = "global";

function f( ) {alert(scope); // Displays "undefined", not "global"var scope = "local"; // Variable initialized here, but defined everywherealert(scope); // Displays "local"}f( );
Right,thought you alert(scope) first and then define a new functin scope variable scope.However,once you define a function scope vriable,it will hide the global variable in the function body,whatever the definition order.

Rasmus Lerdorf, creator of the PHP langauge, has a new tutorial on his site today that looks at the creation of a "no-framework PHP MVC framework" using PHP5, the Yahoo! User Interface Library, and JSON.

He steps through the entire process of working up the "non-framework" - the goals of the project, why to go with the MVC approach for the structure, and, of course, the code.

That arose the PHP's own MVC Pattern discussion in PHP Community.But i have my own view.Here is my response in one of most famous PHP community:

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