A single opening or closing brace inside a character class in a regexp of a @Pattern leads to a MessageDescriptorFormatException, which is caught and swallowed with a warning in ResourceBundleMessageInterpolator.

For an opening brace, the warning is:

WARN: HV000169: The message descriptor 'must match "[{0-9]

Unknown macro: {1,160}

"' has nested parameters.

For a closing brace:

WARN: HV000168: The message descriptor 'must match "[}0-9]

Unknown macro: {1,160}

"' contains an unbalanced meta character '}' parameter.

This was still working in 5.0.0.Final, as bundled with GlassFish 4.1. I ran into the bug with Payara 4.1.1.171.0.1, that's why I put 5.1.2.Final as affected version, but I also verified it still happens with 5.4.0.Final. I suspect it may have to do with https://hibernate.atlassian.net/browse/HV-798.

A test case:

import static org.junit.Assert.assertNotEquals;

import java.util.Set;

import javax.validation.Configuration;
import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.ValidatorFactory;
import javax.validation.constraints.Pattern;

import org.junit.Test;

public class PatternInterpolationTest
{
   @Test
   public void shouldInterpolateRegexWithSingleBraceInCharacterClass() throws Exception
   {
      Configuration<?> config = Validation.byDefaultProvider().configure();

      ValidatorFactory factory = config.buildValidatorFactory();
      Validator validator = factory.getValidator();

      Entity invalidContent = new Entity();
      invalidContent.field = "ABC";

      Set<ConstraintViolation<Entity>> violations = validator.validate( invalidContent );

      for ( ConstraintViolation<Entity> violation : violations )
      {
         assertNotEquals( "{javax.validation.constraints.Pattern.message}", violation.getMessage() );
      }
   }

   private class Entity
   {
      @Pattern( regexp = "[{0-9]{1,160}" )
      private String field;
   }
}