Server/src/engine/documentation/Handler Specific Documentation/dbNPCHandler_Documentation.md

dbNPCHandler Documentation

Overview

This document describes the database relationships and interactions for the dbNPCHandler class. This handler manages non-player character (NPC) data, including their base properties, current state, and behaviors in the game world.

Handler Class

File: src/engine/db/handlers/dbNPCHandler.java Class: dbNPCHandler Extends: dbHandlerBase

Database Tables

Main NPC Table

• Table Name: dyn_npc
• Description: Stores current state information for NPCs, including location, health, and behavior flags
• Columns:
  • UID (Primary Key)
  • npcBaseID
  • zoneUUID
  • x
  • y
  • z
  • health
  • isAlive
  • behavior

Related Tables

Table Name	Description	Relationship
static_npc_base	Base properties of NPCs	npcBaseID → static_npc_base.UID

Key Queries

Get NPC by UID

SELECT * FROM dyn_npc WHERE `UID` = ?

File: dbNPCHandler.java, Line ~25

Save NPC

INSERT INTO `dyn_npc` (`npcBaseID`, `zoneUUID`, `x`, `y`, `z`, `health`, `isAlive`, `behavior`) VALUES(?,?,?,?,?,?,?,?)

File: dbNPCHandler.java, Line ~40

Get NPCs by Zone

SELECT * FROM dyn_npc WHERE `zoneUUID` = ?

File: dbNPCHandler.java, Line ~55

Relationships

1. NPC to NPC Base: Many-to-one relationship via npcBaseID field referencing static_npc_base.UID
2. NPC to Zone: Many-to-one relationship via zoneUUID field referencing obj_zone.UID

Java Field to Database Column Mappings

Java Field	Database Column	Notes
UID	dyn_npc.UID	Unique identifier for the NPC
npcBaseID	dyn_npc.npcBaseID	UID of the base NPC definition
zoneUUID	dyn_npc.zoneUUID	Zone where the NPC is located
x	dyn_npc.x	X coordinate of NPC position
y	dyn_npc.y	Y coordinate of NPC position
z	dyn_npc.z	Z coordinate of NPC position
health	dyn_npc.health	Current health of the NPC
isAlive	dyn_npc.isAlive	Flag indicating if NPC is alive
behavior	dyn_npc.behavior	Behavior type or state of the NPC
other fields...	Various columns	Other properties related to NPC state