How to check a boolean condition in EL?

You can have a look at the EL (expression language) description here.

Both your code are correct, but I prefer the second one, as comparing a boolean to true or false is redundant.

For better readibility, you can also use the not operator:

<c:if test="${not theBooleanVariable}">It's false!</c:if>

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Both works. Instead of == you can write eq

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You can check this way too

<c:if test="${theBooleanVariable ne true}">It's false!</c:if>

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