How to get dynamic property in Velocity Template

Question

I'm facing a difficult problem when I am coding with Velocity Template.

#set($key = "")

$key is a dynamic variable.

So when I want to get the property of another variable which has property is $key. What will I do?

#set($temp = #evaluate("$data.$key");

or

#set($temp = $data.$key);

All of them is not valid. Please help me!!!

score 1 · Accepted Answer · answered Mar 27 '18 at 07:54

1

Since the passed string is evaluated in two steps, you need to escape the first dollar (with a backslash) and the quotes (by doubling them) at the first step. You would do:

#set($temp = "#evaluate(""\$data.$key"")")

answered Mar 27 '18 at 07:54

Claude Brisson

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user7294900 · Answer 2 · 2018-03-26T10:09:01.937

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To access other velocity variable's property you just need to address it as $variableName.propertyName. see velocity properties. in your case:

#set($temp = $data.key);

I don't know of such built-in reflection capabilities, even ClassTool of velocity tools support reflection but not allowing executing:

It was not designed with reflective execution of code in mind and thus provides no facilities for code execution, nor direct access to the actual methods

edited Mar 26 '18 at 10:09

answered Mar 26 '18 at 08:30

user7294900

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Thanks for helping. But as I told, propertyName is dynamic, so I want to access a dynamic property. Can you help me? – Nguyễn Dương Mar 26 '18 at 09:46
I updated my answer. I don't know on any velocity's built in option – user7294900 Mar 26 '18 at 10:10
@Nguyễn Dương for invoking a method dynamically in java see https://stackoverflow.com/questions/160970/how-do-i-invoke-a-java-method-when-given-the-method-name-as-a-string – user7294900 Mar 26 '18 at 14:28
Thank you for your support. I found the solution – Nguyễn Dương Mar 29 '18 at 04:20

score 0 · Answer 3 · answered Jul 09 '20 at 18:02

0

You can use get():

#set( $temp = $data.get($key) )

answered Jul 09 '20 at 18:02

robo

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How to get dynamic property in Velocity Template

3 Answers3