...ave to ask yourself "can this be null? Do I need to check for null here?" Ideally, in the many cases where null doesn't make sense, it shouldn't be allowed. That's tricky to achieve in .NET, where nearly everything can be null. You have to rely on the author of the code you're calling to be 100% d...

...y to user interaction events (like mouse clicks). In this case, the whole idea is to wait for a contingent event to occur before executing the custom functionality. This is obvious in the case of user interaction, but is also important in i/o (input/output) processes that can take time, like readin...

...llows you to inject implementation into your service or whatever. The main idea is that class, where you inject, should be managed by EJB container. Seems that CDI does understand what EJB is, so in Java EE 6 compliant server, in your servlet you can write both @EJB EJBService ejbService; and @Inje...

... experienced programmer or don't have access to an experienced programmer (ideally in PHP and Java), pick another cart. Magento is well engineered, but it was engineered to be a shopping cart solution that other programmers can build modules on top of. It was not engineered to be easily understood b...

...wants you to define a P3P header if you are using cookies. This is a nice idea, and luckily most of the time not providing this header won't cause any issues (read browser warnings). Unless your website/web application is loaded into an other website using an (i)Frame. This is where IE becomes a ma...

... pass You need to understand the implications and why it's often a good idea to be explicit. Case 1: testing if a value is None Why do value is None rather than value==None ? The first is equivalent to: id(value)==id(None) Whereas the expression value==None is in fact applied like this value._...

...er may now seem incredibly silly & out of place. Hopefully the general idea of the story remains fun for some. I'm a big fan of analogy and metaphor when explaining difficult concepts, so let me try my hand with a story. Once upon a time: There was a princess... function princess() { She...

...ver, turning on this warning can enforce something that is probably a good idea. For cases where you explicitly want to ignore everything except the listed possibilities (but other numbers are possible), then put in default: break; to make it explicit. If you explicitly enumerate all possibilities, ...

...or) is called, that we will be wanting a local copy of that argument. The idea is that if we know that we are going to be making a copy, we should let the caller know that we are making a copy by putting it in our argument list. They can then optimize around the fact that they are going to give us...

... There are people who say that this answer is imprecise. I have no idea if this is the case or if they are nitpicking. I just thought i would point to it in case it contains some truth. – surfmuggle Jun 28 '13 at 17:41 ...