我没有发现“c”字段的实用性，但这里有一个解决方案

import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public static void main(final String[] args) {
    String data = "FirstName|Auro\n" +
                  "LastName|Winkies\n" +
                  "Age|26";

    List<String> l = new ArrayList<>();
    List<String> r = new ArrayList<>();
    ObjectNode node = JsonNodeFactory.instance.objectNode();
    List<String> c = Arrays.asList("1,2,3");

    String[] split = data.split("\n");
    for (String s : split) {
        int i = s.indexOf('|');
        l.add(s.substring(0, i));
        r.add(s.substring(i + 1, s.length()));
    }
    node.put("L",l.toString());
    node.put("R",r.toString());
    node.put("C",c.toString());

    System.out.println(node);
}