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A small and useful note (very technical) if you use Spring in your project.

You want to retrieve / increment the value of a database sequence and the Sequence Generator of Hibernate does not meet your needs (see the note).

Rather than go through a DAO with Hibernate code (or worse use JDBC), Spring can do it for you in 2 minutes…

• To do this, simply declare a new bean in the Spring configuration of your project:

        <bean id='mySequenceIncrementer' class='org.springframework.jdbc.support.incrementer.H2SequenceMaxValueIncrementer'>
  	      <property name='dataSource' ref='<Name of your datasource>' />
  	      <property name='incrementerName' value='<Name of your sequence>' />
        </bean>
  

  Note: there are several implementations of incrementer for different databases (I use H2DB but MySQL, PostgreSQL, Oracle, etc. are also available.)

• Inject this bean in the class of your choice.
• And now, you can do:

  final Long newIdSequence = mySequenceIncrementer.nextLongValue();
  

Tested and approved!

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Is it really useful? I think so! People who print pages on the Internet are probably more numerous than one might think. And it takes 5 minutes, so just do it!

Let’s take a screenplay (almost) like in Hollywood movies:

Mister Nextdoor will not have access either to Internet or to his computer this weekend and did not have enough time to read a long article, but very important for what’s happening next. So he decides to print it to read it later on the plane (yes, Mr. Nextdoor is lucky, he is going on vacation). Once the printing is done, he realizes a little jaded (because yes it’s not the first time) that absolutely all the internet page came out. He ends up with 7 printed pages of an article that needed maybe 3… The menu, related articles, social media sharing links… Everything is there! Anyway, Mr. Nextdoor is relieved, he will be able to read his article “How to conquer your fear of flying?”.

To continue on the same idea of the article explaining how to make your site responsive, I will show you how to make your website optimized for print.

Principle is similar by using the CSS language.

You have to declare a dedicated CSS file for printing. In the header of your pages, you have to add a link to this file by specifying “print” for the “media” attribute, unlike others which usually specify the media “all” (screen, printer, etc.). Check out this page to know more about the media types.

In my case, I use a “print.css” file for my blog, so I add this line:

<link rel="stylesheet" href="https://blog.fabianpiau.com/wp-content/themes/freshy2/print.css" type="text/css" media="print">

This CSS style file will be used only in case of printing. Thus, you can use it to remove all unwanted content such as:

• Header
• Sidebars
• Footer
• Related articles
• Etc.

Here is an excerpt of my “print.css” file:

@media print {
	.sidebar div div {
		display:none !important;
	}
	#header {
		display:none !important;
	}
	#footer {
		display:none !important;
	}
	.yarpp-related {
		display:none !important;
	}
	.meta {
		display:none !important;
	}
	.wp-pagenavi {
		display:none !important;
	}
	.sharedaddy {
		display:none !important;
	}
	#breadcrumbs {
		display:none !important;
	}
	.navigation {
		display:none !important;
	}
	.noprint {
		display:none !important;
	}
}

Note: I use the “!important” keyword to redefine a style already present. The value specified with the “!important” will always overwrite the others.

@media print { [my CSS code here] } is useful to make a CSS code interpretable only in case of printing. If you use this annotation around a piece of CSS code, then you can integrate it into a CSS file used for all media (media="all"). I used both the annotation and the “print” media, just to be sure, but this is not mandatory.

Another (often complementary) solution is to add a dedicated CSS class to hide particular elements when printing. This is useful when the item has no specific attributes (no identifier or a too generic CSS class that we don’t want to hide on the whole page…).

For instance, I have this “noprint” class:

.noprint {
	display:none !important;
}

Now, any element of my site that uses the “noprint” class will be hidden when printed. It cannot be easier!

To see the result in action, you can print this article (consider the planet by doing a print preview or printing as a PDF…).