package net.sf.l2j.logserver;

import java.io.File;
import java.io.FileWriter;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

import net.sf.l2j.gameserver.ClientScheduler;
import net.sf.l2j.gameserver.model.L2PcInstance;

public class LogServer extends Thread
{
    private static ArrayList<LogEntry> _data;
    static LogServer _instance;
    private final int POOL_SIZE = 6000;
    private final long FLUSH_INTERVAL = 2;

    public LogServer()
    {
        _data = new ArrayList<LogEntry>(POOL_SIZE);
        ClientScheduler.getInstance().scheduleLowAtFixedRate(new flush(),FLUSH_INTERVAL*60*1000L,FLUSH_INTERVAL*60*1000L);
        start();
    }
    
    public static LogServer getInstance()
    {
        if(_instance == null)
            _instance = new LogServer();
        return _instance;
    }
    
    public void run()
    {
        System.out.println("LogServer thread up&running," +
                           "allocated "+POOL_SIZE+" pool entries, flush interval(minutes): "+FLUSH_INTERVAL);
        while(true)
        {
        }
    }
    
    public synchronized void add(int logid, L2PcInstance actor, String data)
    {
        synchronized(_data)
        {
            LogEntry entry = new LogEntry(logid,actor,data);
            _data.add(entry);
        }
    }
    
    private class flush implements Runnable
    {
        public void run()
        {
            ArrayList<LogEntry> tmp = null;
            
            System.out.println(">> flushing logs, total records: "+_data.size());

            // lock _data array, copy & unlock
            synchronized(_data)
            {
                tmp = new ArrayList<LogEntry>(_data);
                _data.clear();
            }
            
            System.out.println(">> flushing logs, tmp array records: "+tmp.size());
            
            // now long-running flush task, _data now free, so we should avoid thread locking
            String date = (new SimpleDateFormat("yy_MM_dd_H")).format(new Date());
            new File("log/logd").mkdirs();
            File file = new File("log/logd/"+date+"_logd"+".txt");
            FileWriter save = null; 

            for(LogEntry entry : tmp)
            {
                try
                {
                    save = new FileWriter(file, true);
                    String out = "["+entry.getTimestamp()+"]:"
                                    +entry.getLogId()+","
                                    +entry.getActor()+","
                                    +entry.getTarget()+","
                                    +entry.getData()
                                    +"\n";
                    save.write(out);
                }
                catch (Exception e)
                {
                    System.out.println("Error flushing log data: "+e);
                    e.printStackTrace();
                }
                finally
                {
                    try { save.close(); } catch (Exception e1) { }
                }
            }

        }
    }
    
    private class LogEntry
    {
        private int _logid;
        private String _actor;
        private int _target;
        private String _data;
        private long timestamp;

        public LogEntry(int logid, L2PcInstance actor, String data)
        {
            _logid = logid;
            _actor = actor.getName();
            _data = data;
            
            if(actor.getTarget() != null)
                _target = actor.getTarget().getObjectId();
            
            timestamp = System.currentTimeMillis();
        }
        
        public int getLogId()
        {
            return _logid;
        }
        
        public int getTarget()
        {
            return _target;
        }
        
        public String getActor()
        {
            return _actor;
        }
        
        public String getData()
        {
            return _data;
        }
        
        public long getTimestamp()
        {
            return timestamp;
        }
    }
}


example:

//BuyLust.java, after line 241:
LogServer.getInstance().add(901,activeChar,item.getItemId()+","+item.getCount()+","+(subTotal + tax));

and u got in logs:

[1129997620195]:901,SAYMON,268437320,2509,39,663

[timestamp]:logid,actor,targetid,item,amount,price