Generate a Json from Strings using Jackson library
A few things:


Use descriptive variable names. A common Java convention is a camelCase version of the class name such as JsonMapper jsonMapper = new JsonMapper();
Unwrap your classes into separate files. This makes the code much easier to read and reuse.
test in your package name is very unusual, and probably not intended.
Test classes typically have the same name as the class they test suffixed with Test, such as JsonMapperTest.
Tests are not written in main methods.
Having getters and setters for everything is a code smell - not necessarily bad, but often misused. Your application doesn't do anything yet, so it's difficult to tell whether any of them will be necessary, but in general I would not add getters and setters until I know I need them.