Here is a basic example of how to use the AnnotationIntrospector class in the com.fasterxml.jackson.databind package in Java:

import com.fasterxml.jackson.databind.AnnotationIntrospector;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;

public class Example {
    public static void main(String[] args) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        AnnotationIntrospector introspector = new JacksonAnnotationIntrospector();
        mapper.setAnnotationIntrospector(introspector);
    }
}

In this example, we are importing the AnnotationIntrospector and ObjectMapper classes, as well as the JacksonAnnotationIntrospector class from the com.fasterxml.jackson.databind.introspect package. We then create an instance of the ObjectMapper class, and create an instance of the JacksonAnnotationIntrospector class, which is a concrete implementation of the AnnotationIntrospector interface. Finally, we set the AnnotationIntrospector on the ObjectMapper instance.

This example is just a basic usage. you can use this class to customize the way Jackson reads and writes JSON.