有没有一种方法可以将 Java 代码嵌入到 YAML 文件中以在运行时进行处理。

Question

I know ruby has this facility using ERB. But does Java have this capability? I'm trying to do something like this:

MY.yaml CURRENT_DATE: <%=LocalDateTime.now()%>

Answer 1

Ya, the classic way is using Java server pages https://en.wikipedia.org/wiki/JavaServer_Pages Something like

Date : <% Date() %>
myArray:
<% for (int i=1; i<4; i++) { %>
    - This  is <% i %> th element.
<% } %>

For modern curly bracket based templating use www.thymeleaf.org, or better JTwig with double curly braces and other cool features

 CurrentDate: {{ "now"|date("m/d/Y") }}

https://twig.symfony.com/doc/2.x/filters/date.html

Answer 2

I had a similar requirement where a YAML had an expression which needed to be parsed in runtime in Java.

We ended up using MVEL for this. We read the contents of the yaml and passed the expression to MVEL. Its syntax is quite similar to that of Java.

You could also try other template library like Velocity Template .