PerformanceAnalyzer

[2.2.0] - 2026-01-05

🏗️ Major Release - Stability & Performance Update

This release focuses on security hardening, graceful degradation, performance optimizations, and critical bug fixes to ensure stable operation on production servers.

🔐 Security Hardening

SQL Injection Prevention

• Type-Safe Database Queries
  • New TimeUnit enum for SQL time unit operations
  • Replaces dangerous string concatenation in DatabaseManager
  • Prevents SQL injection attacks via time-based queries
  • Enum values: SECOND, MINUTE, HOUR, DAY
  • Each value provides safe SQL name via getSqlNameUpper()

SSRF Protection

• Discord Webhook URL Validation
  • Protocol validation: HTTPS-only (HTTP rejected)
  • Domain whitelist: Only discord.com and discordapp.com allowed
  • Path validation: Must start with /api/webhooks/
  • Prevents Server-Side Request Forgery attacks
  • Logs validation failures for security monitoring

Memory Leak Prevention

• Size Limits on All Maps
  • XRayDetector.playerPlacedBlocks - Max size: 10,000 entries
  • XRayDetector.playerOreMines - NEW: Max size: 5,000 players
  • XRayDetector.playerStoneMines - NEW: Max size: 5,000 players
  • MovementChecker.moveCounter - Periodic reset at threshold
  • Automatic cleanup routines prevent unbounded growth
  • Warning logs when size limits are hit
  • Debug logging shows cleanup statistics and map sizes

💾 Graceful Degradation

FallbackLogger System

• Automatic Database Failover
  • Queue-based async file writing (ConcurrentLinkedQueue)
  • CSV format: timestamp | type | value | description
  • Detects 3 consecutive database failures
  • Switches to file logging automatically
  • Configurable flush threshold (default: 100 entries)
  • File rotation and management
  • Fallback file path: plugins/PerformanceAnalyzer/fallback.log

Database Availability Monitoring

• Failure Detection
  • isDatabaseAvailable() method for health checks
  • Consecutive failure counter
  • Automatic recovery detection (resets to DB logging)
  • Logs critical warnings when switching modes

Configuration

fallback_logging:
  enabled: true
  file: "plugins/PerformanceAnalyzer/fallback.log"

⚡ Performance & Reliability

AsyncConfigSaver (CRITICAL FIX)

• Thread-Safe Config Operations
  • FIXED: Now uses Bukkit Scheduler instead of ForkJoinPool
  • CRITICAL: saveConfig() runs on main thread (Bukkit requirement)
  • Previously used CompletableFuture.runAsync() which caused ConcurrentModificationException
  • Uses CompletableFuture for async pattern
  • Atomic boolean flags prevent concurrent saves
  • saveAsync() schedules on main thread via runTask()
  • saveSyncOnShutdown() ensures data persistence on server stop
  • Error handling with exception logging and stack traces
  • Prevents thread-safety violations and data corruption

Performance Optimizations

• Event Sampling - Movement checks reduced by ~90%

  • Only every 10th PlayerMoveEvent processed
  • OR significant distance (>2 blocks) always checked
  • Counter reset at 1000 to prevent overflow
  • Minimal detection accuracy loss

• Database Indexing

  • Indexes on timestamp column for time-range queries
  • Indexes on type column for metric filtering
  • Significantly faster query performance
  • Auto-created during database initialization

Constants Class

• Centralized Configuration
  • 255 lines of well-organized constants
  • Categories: Database, Discord, Movement, XRay, Performance, Vehicle Speeds
  • No more magic numbers scattered throughout codebase
  • Easy to tune and maintain
  • All values documented with comments

🏗️ Architecture Improvements

CommandRegistry System

• Modular Command Registration
  • Replaces 112-line monster method in PerformanceAnalyzer
  • Separate methods for each category:
    • registerPerformanceCommands() - /perfstatus, /perfhistory, /perfreload
    • registerAnalysisCommands() - /worldstats, /entitystats, /chunkstats, /perfdrops
    • registerGUICommands() - /perfgui
    • registerAntiCheatCommands() - /acwhitelist, /xrayalerts, /movealerts, /xrayores
  • Easy to extend with new commands
  • Clean separation of concerns
  • AntiCheat commands dynamically registered when module enabled

ConfigMigrator Class

• Extracted Migration Logic
  • Separate class for config version upgrades
  • Version-by-version migration (v0 → v1 → v2 → ... → v5)
  • Only runs when config_version < Constants.CONFIG_VERSION
  • Returns boolean if changes were made
  • Cleaner PluginConfig class (separation of concerns)
  • Easy to add new migrations

Public API

• PerformanceAPI Interface
  • double getCurrentTPS() - Get current server TPS
  • double getCurrentMSPT() - Get current MSPT
  • boolean isPlayerSuspicious(UUID playerUUID) - Check if player flagged
  • Enables third-party plugin integration
  • Future: Additional methods for detailed performance data

🐛 Critical Bug Fixes

DatabaseManager Exception Handling

• FIXED: Added missing stack traces to SQL exceptions
• IMPROVED: Now logs failed SQL statements for debugging
• ADDED: JavaDoc documentation for run() method
• Better error messages for database initialization failures
• Prevents silent failures during schema creation

XRayDetector Map Size Enforcement

• FIXED: Unbounded memory growth in playerOreMines and playerStoneMines
• ADDED: Hard limit of 5,000 player entries per map
• IMPROVED: Cleanup task now removes empty playerStoneMines entries
• Warning logs when size limit is exceeded
• Debug output shows current map sizes

Config.yml Language Consistency

• FIXED: All comments now in English (was mixed German/English)
• Consistent with multi-language support design
• User-facing messages still use language files (en.yml/de.yml)
• Better for international plugin distribution

🔧 Code Quality Improvements

• Consistent Error Handling - All exceptions logged with stack traces
• English Logging - All console logs in English (user-facing messages use i18n)
• Null Safety - Extensive null checks before operations
• Improved Documentation - JavaDoc added to critical methods
• Code Comments - All config comments translated to English

📦 New Files Created

• util/Constants.java - Centralized constants
• commands/CommandRegistry.java - Modular command registration
• config/ConfigMigrator.java - Config migration logic
• config/AsyncConfigSaver.java - Async config saves
• db/FallbackLogger.java - Fallback file logging
• db/TimeUnit.java - SQL-safe time units
• api/PerformanceAPI.java - Public API interface

🔧 Modified Files

• PerformanceAnalyzer.java - CommandRegistry integration, version update to 2.2.0
• DatabaseManager.java - CRITICAL FIX: Stack traces, SQL logging, FallbackLogger, TimeUnit enum, failure detection
• AsyncConfigSaver.java - CRITICAL FIX: Thread-safety with Bukkit Scheduler
• PluginConfig.java - AsyncConfigSaver, ConfigMigrator, fallback config methods
• DiscordWebhook.java - URL validation, SSRF protection
• MovementChecker.java - Constants usage, event sampling
• XRayDetector.java - CRITICAL FIX: Size limits (5000 players), improved cleanup, memory leak prevention
• Constants.java - NEW: XRAY_MAX_PLAYER_ENTRIES constant
• config.yml - FIXED: All comments translated to English
• pom.xml - Version 2.2.0

⚠️ Breaking Changes

None - This release is fully backward compatible with v2.1.0.

• All new features have sensible defaults
• Existing configs auto-migrate
• No database schema changes
• No API changes to existing methods

📊 Configuration Changes

New Config Sections:

# Graceful Degradation 
fallback_logging:
  enabled: true
  file: "plugins/PerformanceAnalyzer/fallback.log"

Auto-Migration:

• Config auto-migrates from v5 to v5 (no version bump needed)
• New fallback_logging section added automatically
• Existing settings preserved

🔄 Migration Guide (from v2.1.0)

1. Backup - Backup your plugins/PerformanceAnalyzer/ folder
2. Stop Server - Stop your server
3. Replace JAR - Replace old JAR with PerformanceAnalyzer-2.2.0.jar
4. Start Server - Start your server
5. Auto-Migration - Config auto-updates (check console for "Config migrated")
6. Verify - Run /perfstatus to ensure plugin loaded correctly

Optional Post-Migration:

• Review fallback logging settings in config.yml
• Check fallback.log file (created only on database failure)

📈 Performance Impact

• CPU Usage: Reduced ~90% for movement checks (event sampling)
• Memory Usage: Lower (cleanup routines, size limits)
• Disk I/O: Reduced (async config saves, fallback only on failure)
• Database Load: Reduced (batching, indexing)
• Startup Time: Unchanged

🐛 Known Issues

None - All known issues from v2.1.0 have been resolved, including:

• ✅ AsyncConfigSaver thread-safety violation (ConcurrentModificationException)
• ✅ DatabaseManager silent failures (missing stack traces)
• ✅ XRayDetector unbounded memory growth (5000+ players)
• ✅ Config.yml mixed language comments (now all English)

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