Comparing the enum constants in thymeleaf

Question

I have an enum, Constants:

enum Constants {
    ONE,TWO,THREE;
}

How can I compare the enum Constants in Thymeleaf.

Thank

Answer 1

I prefere use wrapper around the enum.

public class ConstantsWrapper {
    public static final instance = new ConstantsWrapper();
    public Constants getONE() { return Constants.ONE }
    public Constants getTWO() { return Constants.TWO }
    public Constants getTHREE() { return Constants.THREE }
} 

Next step is adding new instance of Wrapper into models

models.add("constantsWrapper", ConstantsWrapper.instance);

Now you have type safe access in thymeleaf template to the each value of Constants.

th:if="${value == constantsWrapper.getONE()}"

I know that this solutions needs to write more source code and create one instnace. Advantage is more type safe than call T() and write full qualified name directly into template. With this solution you can refactor without testing your templates.