Writing a simple mapper in Java

This can be done using the Jackson library and can be very useful in small to medium data transformation applications!

import com.fasterxml.jackson.databind.ObjectMapper;

public class DataFormatMapper {

    public static void main(String[] args) throws Exception {
        // Initialize the object mapper
        ObjectMapper mapper = new ObjectMapper();

        // Define the source data in the original format
        String sourceData = "{\"name\":\"John\",\"age\":30,\"address\":{\"street\":\"Main St\",\"city\":\"New York\"}}";

        // Define the target data format
        class TargetData {
            public String firstName;
            public int age;
            public String city;
        }
   // Use the object mapper to convert the source data to the target data format
        TargetData targetData = mapper.readValue(sourceData, TargetData.class);

        // Print the mapped data to the console
        System.out.println(targetData.firstName); // "John"
        System.out.println(targetData.age); // 30
        System.out.println(targetData.city); // "New York"
    }
}

In this example, the source data is in JSON format and has fields “name”, “age”, and “address”. The target data format is defined as a Java class with fields “firstName”, “age”, and “city”. The ObjectMapper’s readValue() method is used to convert the source data to an instance of the TargetData class, which effectively maps the data from one format to the other.

This is just a simple example, you can use the Jackson library to map more complex data structures and formats.