how to check api working or not code example

Example: have you done api testing

I have worked on API testing in my project and I used
POSTMAN for manually testing and REST ASSURED
java LIBRARY for automation.
I used JDBC and it is a Java-based data access technology
used for Java database connectivity. It provides classes and
interfaces to connect or communicate Java application with
database.
JDBC API is a Java API that can access any kind of data
stored in a Relational Database. It enables Java programs to
execute SQL statements.