Config Loading

ConfigManager reads a YAML file, deserializes it into any POJO that implements Config, and validates it using JSR-380 constraint annotations. An IOException is thrown if the file cannot be read; IllegalStateException if any constraint is violated.

Define a config class

import com.crimsonwarpedcraft.cwcommons.config.Config;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonProperty;
import jakarta.validation.constraints.Max;
import jakarta.validation.constraints.Min;
import jakarta.validation.constraints.NotBlank;

@JsonIgnoreProperties(ignoreUnknown = true)
public class PluginConfig implements Config {

    @NotBlank
    @JsonProperty("server-name")
    private String serverName = "My Server";

    @Min(1) @Max(100)
    @JsonProperty("max-players")
    private int maxPlayers = 20;

    public String getServerName() { return serverName; }
    public int getMaxPlayers() { return maxPlayers; }
}

Load in onEnable()

import com.crimsonwarpedcraft.cwcommons.config.ConfigManager;
import java.io.File;

// Write defaults if the file doesn't exist yet
saveDefaultConfig();
File configFile = new File(getDataFolder(), "config.yml");

PluginConfig config = new ConfigManager().load(configFile, PluginConfig.class);
getLogger().info("Server name: " + config.getServerName());

config.yml

server-name: "Survival World"
max-players: 50

Validate an object without loading from disk

PluginConfig cfg = new PluginConfig();
new ConfigManager().validate(cfg); // throws IllegalStateException if invalid

Jackson, Hibernate Validator, and Jakarta Validation are provided as transitive dependencies. If you shade your plugin, include and relocate them under your own namespace to avoid conflicts with other plugins on the same server.