Spring @Value empty list as default

java spring spring-annotations
Roby Rodriguez picture Roby Rodriguez · Mar 21, 2017 · Viewed 22k times · Source

Is there a way to set an empty list as default value for a property in Spring, something like:

@Value("${my.list.of.strings :" + new ArrayList<>() + "}")
private List<String> myList;

Obviously not new ArrayList, but I need an empty list there instead.

Answer

Roby Rodriguez picture Roby Rodriguez · Mar 21, 2017

After taking a look at SpEL specification and combined with @javaguy's answer I came up with this:

@Value("${my.list.of.strings:}#{T(java.util.Collections).emptyList()}")
private List<String> myList;

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