Difference between TestNG @BeforeClass and test class constructor

Question

What is the difference between TestNG's @BeforeClass and the test class' constructor? How does it work internally?

Answer 1

1. @BeforeClass methods are invoked after test class instantiation.
2. Exceptions in constructor will just abort TestNG test execution and no report will be created. Whereas exceptions in @BeforeClass will be displayed in resulting report and class test methods will be skipped (This behaviour can be tweaked using -configfailurepolicy TestNG parameter).