Using Freemarker to generate Java .properties files

Question

I am currently using Freemarker to generate a number of configuration files. So far these have been either xml files or properietary format text files. I now would like to generate some Java .properties files but have hit a couple of issues.

The first is character encoding. As far as I can see simply adding

<#ftl encoding="8859_1">

to the start of the file should sort this out.

The second issue is the escaping of the keys and values. The keys are probably ok as I would be hardcoding these in the template anyway so I can escape them in the template. The values will be coming from my data model and so will need escaping.

I can see how I can create my own user defined directive and by installing it as a shared variable use it in my template.

Is this the best or only way to do this? I would have thought generating .properties files is something that has been tackled many times before and was hoping something may already exist before I start writing my own code.

Answer 1

The class java.util.Properties got various store methods to save properties to OutputStreams or files. This seems more preferable than trying to adapt freemarker.

Answer 2

I don't get what are the charset issues that are specific to generating properties files. But note that the charset of the template and the charset of the output are independent, so you might as well use the same charset for these templates as for the others (like maybe UTF-8).

As of escaping, always use auto-escaping if you can. In 2.3.24 that will be especially sleek, but unless you are allowed to use unreleased versions, you had to wait for that until the end of February or so. (If you can use unreleased/unofficial versions, you can find out about the internal testing releases in the developer list archive.) Before 2.3.24, there's <#escape x as propEsc(x)>all the template content here</#escape> , where propEsc is a TemplateMethodModelEx (not a TemplateDirectiveModel ) that you have added as shared variable or such. And so all ${...} -s will be magically escaped.