import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;

import java.io.IOException;

public class StringArrayDeserializer extends StdDeserializer<String[]> {

    public StringArrayDeserializer() {
        super(String[].class);
    }

    @Override
    public String[] deserialize(JsonParser parser, DeserializationContext context) throws IOException {
        if (parser.getCurrentToken() == JsonToken.START_ARRAY) {
            return parser.readValueAs(String[].class);
        } else {
            throw context.mappingException("Expected array, got: " + parser.getCurrentToken());
        }
    }
}

This is an example of a custom deserializer for a String[] type in Jackson. This class extends StdDeserializer and overrides the deserialize method to handle converting a JSON array to a String[] instance.

It checks if the current token is a START_ARRAY token, if it is, it uses parser.readValueAs(String[].class) to deserialize the JSON array to a String[] instance.

Otherwise, it throws a MappingException which indicates that the input is not in the correct format.

You will need to use this deserializer along with ObjectMapper.registerModule() method to register this deserializer to be used by the ObjectMapper.