validation error message {0} is not working

[suzukitadashi]

Application

• Spring boot 2.1.5.RELEASE
• Sample : https://github.com/suzukitadashi/validationMessageCheck
• Blog : http://tadashi.hatenablog.com/entry/2019/05/22/095656 (Sorry, Japanese only...)

config

ValidationMessages.properties

javax.validation.constraints.NotEmpty.message={0} must not be empty
javax.validation.constraints.Size.message=size must be between {min} and {max},please.

value=value1111 

Form

@Setter
@Getter
public class TestForm {

	@NotEmpty
	@Size(min=5, max=100)
	String value;
	
}

run

http://localhost:8080/test

Press the button without inserting anything.

Result

Spring boot 2.1.4

Error messages is no problem.

size must be between 5 and 100,please.

value1111 must not be empty

Spring boot 2.1.5

Error message is...

size must be between 5 and 100,please.

{0} must not be empty

I want to set the value in the part of {0}.
Do you need to do something?

[jhoeller]

This seems to be caused by the recent changes behind #22761, taking native Bean Validation messages at face value and not applying java.text.MessageFormat to them if they are not expected to contain placeholders, for the purpose of avoiding unwanted side effects from MessageFormat escaping.

It looks like you are trying to use a {0} placeholder in the Bean Validation message format where it is not actually supported; it was rather just meant to work in Spring ResourceBundleMessageSource bundle files. I see that it would also have worked in a Spring integration scenario when defined in ValidationMessages.properties, so I'll try to make this a bit smarter for 5.1.8.

To be clear, a {0} placeholder for the affected field name is not going to ever work in ValidationMessages.properties with regular Bean Validation setup outside of Spring. You may just reference constraint annotation properties by name there, not Spring-provided arguments (such as the field name) by index; the latter only works in a Spring setup.