I apologize, but there is no such class as "JsonPointer" in the Apache Commons IO library. It seems that you might be confusing it with the class JsonPointer from the Jackson library, which provides a way to navigate and access values in a JSON document using a string-based "pointer" notation.

Here is an example of using the JsonPointer class from the Jackson library to access a specific value in a JSON object:

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.JsonPointer;

public class JsonPointerExample {
    public static void main(String[] args) throws IOException {
        String json = "{\"name\":\"John Doe\",\"age\":30,\"isEmployed\":true,\"address\":{\"city\":\"New York\",\"state\":\"NY\"}}";
        ObjectMapper mapper = new ObjectMapper();
        JsonNode jsonNode = mapper.readTree(json);

        JsonPointer pointer = JsonPointer.compile("/name");
        JsonNode nameNode = jsonNode.at(pointer);
        System.out.println("Name: " + nameNode.asText());

        pointer = JsonPointer.compile("/address/city");
        JsonNode cityNode = jsonNode.at(pointer);
        System.out.println("City: " + cityNode.asText());
    }
}

In this example, we first parse a JSON string into a JsonNode object using the Jackson ObjectMapper. We then use the JsonPointer.compile(String) method to create a JsonPointer object for a specific path in the JSON document. We use the at(JsonPointer) method of the JsonNode object to navigate to that path and get the corresponding JsonNode object.

This example will output:

Name: John Doe
City: New York

You can also use the get(JsonPointer) method instead of at(JsonPointer) to access a value, if the value doesn't exist, it will throw an exception.