Velocity Templates and Newlines
If you're reading this article you've probably encounted the same problem as I have. I was trying to put a newline '\n' character in the value of a variable in a Velocity template. Attempt 1: I assumed \n would work... ``` #if ( !$foo ) #set ( $foo = "There was no foo set in the Context.\nPlease do something about it." ) #end ``` This produced There was no foo set in the Context.\nPlease do something about it. as the value of $foo. Attempt 2: I just thought this was worth a shot :D ``` #if ( !$foo ) #set ( $foo = "There was no foo set in the Context. Please do something about it." ) #end ``` And the template failed to compile Solution: Basically, the easiest way I found is to place the newline, carriage return or other special character in the context. java public Template handleRequest( HttpServletRequest request, HttpServletResponse response, Context context ) { ... context.put( "nl", "\n" ); context.put( "cr", "\r" ); ... }
And in your template: ``` #if ( !$foo ) #set ( $foo = "There was no foo set in the Context.${nl}Please do something about it." ) #end ``` Maybe not the best solution but it works for me. If you expect to use it across your entire application I suggest you override VelocityServlet.createContext in your Servlet to add these characters to every context in your application. Example: ```java
protected Context createContext( HttpServletRequest request, HttpServletResponse response ) { Context context = super.createContext( request, response ); context.put( "nl", "\n" ); context.put( "cr", "\r" ); return context; }
Related Posts
Velocimacro - Generate a HTML Select box and its Options
A quick and simple Velocimacro to generate HTML Select boxes and its Options; automatically selects the correct option based on the value given.
Velocity If Statement is Type Sensitive
Learn how type sensitivity in Velocity template comparisons can break your HTML forms and how to fix it with proper type conversion