Parsing YAML with Nested Structures in Java - Handling Arrays and Scalars
I've searched everywhere and can't find a clear answer... This might be a silly question, but I'm working on a Java application using SnakeYAML to parse a YAML configuration file. The YAML file contains nested structures with both arrays and scalars, and I'm struggling to extract the values correctly. The structure looks something like this: ```yaml servers: - name: server1 ip: 192.168.1.1 ports: - 80 - 443 - name: server2 ip: 192.168.1.2 ports: - 8080 - 8443 ``` I want to read the names and IP addresses of the servers as well as their port numbers into a custom Java object. Here's what I've tried so far: ```java import org.yaml.snakeyaml.Yaml; import java.io.InputStream; import java.util.List; import java.util.Map; public class YamlParser { public static void main(String[] args) { Yaml yaml = new Yaml(); InputStream inputStream = YamlParser.class .getClassLoader() .getResourceAsStream("config.yaml"); Map<String, List<Map<String, Object>>> data = yaml.load(inputStream); for (Map<String, Object> server : data.get("servers")) { String name = (String) server.get("name"); String ip = (String) server.get("ip"); List<Integer> ports = (List<Integer>) server.get("ports"); System.out.println(name + " - " + ip + " - " + ports); } } } ``` However, when I run this code, I encounter a `ClassCastException` on the line where I cast the `ports` list to a `List<Integer>`. The stack trace indicates that the actual type is `List<Double>`. I suspect this is due to YAML's way of interpreting numeric values. How can I address this scenario? Is there a better way to define the type of the list while parsing? I would appreciate any guidance on best practices for parsing this kind of nested YAML structure in Java. What's the best practice here? My development environment is Windows. For context: I'm using Java on CentOS. Am I missing something obvious?