Snapwork Technology L1 Software Engineer interview questions

1) Difference Comparable and Comparator 2) How to create immutable class 3) What is stream API 4) {10,13,27,33,8 ,1 30} second heighest number using stream api 5) {10,13,27,33,8 ,1 30} {10,13,27,33,8 ,1 30,1,44,65} merge 2 array list in single array list using stream api 6) Remove Duplicate in latest arrays 7) What is @SpringBoot Application 8) What is spring Profiles 9) What is API Gateway 10) What is MYSQL primary key and foreign key 11) How to create index in mysql 12) employe table empname, salary, joining_date query for employee list who join last 30 days