package com.baeldung; import static org.junit.jupiter.api.Assertions.assertThrows; import org.junit.jupiter.api.Test; public class AssertionTest { @Test public void testConvertToDoubleThrowException() { String age = "eighteen"; assertThrows(NumberFormatException.class, () -> { convertToInt(age); }); assertThrows(NumberFormatException.class, () -> { convertToInt(age); }); } private static Integer convertToInt(String str) { if (str == null) { return null; } return Integer.valueOf(str); } }