A handy matcher allowing you to assert that a bean is JSR-303 compliant. Usage might look like: `assertThat(beanUnderTest,is(valid));`

ValidationMatcher.java

package com.pillartechnology.matchers;

import java.util.HashSet;
import java.util.Set;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;

import org.hamcrest.Description;
import org.hamcrest.Factory;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeMatcher;

public class ValidationMatcher extends TypeSafeMatcher<Object> {

	private static Validator validator = Validation.buildDefaultValidatorFactory().getValidator();

	private Set<String> validationMessages = new HashSet<String>();

	@Override
	public boolean matchesSafely(Object bean) {
		Set<ConstraintViolation<Object>> violations = validator.validate(bean);
		for (ConstraintViolation<Object> constraintViolation : violations) {
			validationMessages.add(constraintViolation.getPropertyPath().toString() + " " + constraintViolation.getMessage());
		}
		return violations.size() == 0;
	}

	public void describeTo(Description description) {
		description.appendText("invalid with errors: ");
		for (String msg : validationMessages) {
			description.appendText(msg + "\n");
		}
	}

	@Factory
	public static <T> Matcher<Object> valid() {
		return new ValidationMatcher();
	}
}