diff --git a/build.gradle b/build.gradle
index cf1b553..6690eb9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,6 +6,7 @@ apply plugin: 'java'
 apply plugin: 'application'
 apply plugin: 'idea'
 apply plugin: 'eclipse'
+apply plugin: 'findbugs'
 
 repositories {
     mavenCentral()
@@ -34,6 +35,7 @@ dependencies {
 
     compileOnly 'org.projectlombok:lombok:1.16.20'
     apt "org.projectlombok:lombok:1.16.20"
+    compileOnly 'com.google.code.findbugs:annotations:3.0.1'
 }
 
 sourceSets {
diff --git a/src/lwjake2/client/CL.java b/src/lwjake2/client/CL.java
index 05e3285..6866ae3 100644
--- a/src/lwjake2/client/CL.java
+++ b/src/lwjake2/client/CL.java
@@ -30,7 +30,8 @@ import lwjake2.qcommon.CM;
 import lwjake2.qcommon.Cbuf;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.MSG;
 import lwjake2.qcommon.Netchan;
 import lwjake2.qcommon.SZ;
@@ -56,6 +57,8 @@ import java.nio.ByteOrder;
  */
 @Slf4j
 public final class CL {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
+
     static int precache_check; // for autodownload of precache items
 
     static int precache_spawncount;
@@ -159,10 +162,10 @@ public final class CL {
                 //
                 // open the demo file
                 //
-                name = FS.Gamedir() + "/demos/" + Cmd.Argv(1) + ".dm2";
+                name = fileSystem.getGamedir() + "/demos/" + Cmd.Argv(1) + ".dm2";
 
                 log.info("recording to {}", name);
-                FS.CreatePath(name);
+                fileSystem.createPath(name);
                 Globals.cls.demofile = new RandomAccessFile(name, "rw");
                 if (Globals.cls.demofile == null) {
                     log.error("ERROR: couldn't open.");
@@ -973,8 +976,7 @@ public final class CL {
                     // checking for skins in the model
                     if (CL.precache_model == null) {
 
-                        CL.precache_model = FS
-                                .LoadFile(Globals.cl.configstrings[CL.precache_check]);
+                        CL.precache_model = fileSystem.loadFile(Globals.cl.configstrings[CL.precache_check]);
                         if (CL.precache_model == null) {
                             CL.precache_model_skin = 0;
                             CL.precache_check++;
@@ -986,8 +988,6 @@ public final class CL {
                         int header = bb.getInt();
 
                         if (header != qfiles.IDALIASHEADER) {
-                            // not an alias model
-                            FS.FreeFile(CL.precache_model);
                             CL.precache_model = null;
                             CL.precache_model_skin = 0;
                             CL.precache_check++;
@@ -1025,7 +1025,6 @@ public final class CL {
                         CL.precache_model_skin++;
                     }
                     if (CL.precache_model != null) {
-                        FS.FreeFile(CL.precache_model);
                         CL.precache_model = null;
                     }
                     CL.precache_model_skin = 0;
@@ -1408,7 +1407,7 @@ public final class CL {
 //        if (Globals.cls.state == Defines.ca_uninitialized)
 //            return;
 
-        path = FS.Gamedir() + "/config.cfg";
+        path = fileSystem.getGamedir() + "/config.cfg";
         f = Lib.fopen(path, "rw");
         if (f == null) {
             log.warn("Couldn't write config.cfg.");
@@ -1609,7 +1608,7 @@ public final class CL {
         InitLocal();
         IN.Init();
 
-        FS.ExecAutoexec();
+        fileSystem.execAutoexec();
         Cbuf.Execute();
     }
 
diff --git a/src/lwjake2/client/CL_ents.java b/src/lwjake2/client/CL_ents.java
index b0b6f8a..a71fb5a 100644
--- a/src/lwjake2/client/CL_ents.java
+++ b/src/lwjake2/client/CL_ents.java
@@ -24,7 +24,8 @@ import lwjake2.game.entity_state_t;
 import lwjake2.game.player_state_t;
 import lwjake2.game.pmove_t;
 import lwjake2.qcommon.Com;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.MSG;
 import lwjake2.util.Math3D;
 
@@ -40,6 +41,7 @@ import lwjake2.util.Math3D;
  * =========================================================================
  */
 public class CL_ents {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
 	static int bitcounts[] = new int[32]; /// just for protocol profiling
 
@@ -815,7 +817,7 @@ public class CL_ents {
 				 *  
 				 */
 				if ((renderfx & Defines.RF_SHELL_HALF_DAM) != 0) {
-					if (FS.Developer_searchpath(2) == 2) {
+					if (fileSystem.developer_searchpath(2) == 2) {
 						// ditch the half damage shell if any of red, blue, or
 						// double are on
 						if ((renderfx & (Defines.RF_SHELL_RED | Defines.RF_SHELL_BLUE | Defines.RF_SHELL_DOUBLE)) != 0)
@@ -824,7 +826,7 @@ public class CL_ents {
 				}
 
 				if ((renderfx & Defines.RF_SHELL_DOUBLE) != 0) {
-					if (FS.Developer_searchpath(2) == 2) {
+					if (fileSystem.developer_searchpath(2) == 2) {
 						// lose the yellow shell if we have a red, blue, or
 						// green shell
 						if ((renderfx & (Defines.RF_SHELL_RED | Defines.RF_SHELL_BLUE | Defines.RF_SHELL_GREEN)) != 0)
diff --git a/src/lwjake2/client/CL_parse.java b/src/lwjake2/client/CL_parse.java
index 05d2546..8250d3f 100644
--- a/src/lwjake2/client/CL_parse.java
+++ b/src/lwjake2/client/CL_parse.java
@@ -27,7 +27,8 @@ import lwjake2.qcommon.CM;
 import lwjake2.qcommon.Cbuf;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.MSG;
 import lwjake2.qcommon.SZ;
 import lwjake2.render.model_t;
@@ -43,6 +44,8 @@ import java.io.RandomAccessFile;
  */
 @Slf4j
 public class CL_parse {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
+
     //// cl_parse.c -- parse a message received from the server
 
     public static String svc_strings[] = { "svc_bad", "svc_muzzleflash",
@@ -56,7 +59,7 @@ public class CL_parse {
     //	  =============================================================================
 
     public static String DownloadFileName(String fn) {
-        return FS.Gamedir() + "/" + fn;
+        return fileSystem.getGamedir() + "/" + fn;
     }
 
     /*
@@ -74,7 +77,7 @@ public class CL_parse {
             return true;
         }
 
-        if (FS.FileLength(filename) > 0) { // it exists, no need to download
+        if (fileSystem.fileLength(filename) > 0) { // it exists, no need to download
             return true;
         }
 
@@ -147,7 +150,7 @@ public class CL_parse {
                 return;
             }
 
-            if (FS.LoadFile(filename) != null) { // it exists, no need to
+            if (fileSystem.loadFile(filename) != null) { // it exists, no need to
                 // download
                 Com.Printf("File already exists.\n");
                 return;
@@ -221,7 +224,7 @@ public class CL_parse {
         if (Globals.cls.download == null) {
             String name = DownloadFileName(Globals.cls.downloadtempname).toLowerCase();
 
-            FS.CreatePath(name);
+            fileSystem.createPath(name);
 
             Globals.cls.download = Lib.fopen(name, "rw");
             if (Globals.cls.download == null) {
@@ -320,10 +323,10 @@ public class CL_parse {
 
         // set gamedir
         if (str.length() > 0
-                && (FS.fs_gamedirvar.string == null
-                        || FS.fs_gamedirvar.string.length() == 0 || FS.fs_gamedirvar.string
+                && (fileSystem.getGamedirVar().string == null
+                        || fileSystem.getGamedirVar().string.length() == 0 || fileSystem.getGamedirVar().string
                         .equals(str))
-                || (str.length() == 0 && (FS.fs_gamedirvar.string != null || FS.fs_gamedirvar.string
+                || (str.length() == 0 && (fileSystem.getGamedirVar().string != null || fileSystem.getGamedirVar().string
                         .length() == 0)))
             Cvar.Set("game", str);
 
diff --git a/src/lwjake2/client/Console.java b/src/lwjake2/client/Console.java
index 6defe61..0719d5f 100644
--- a/src/lwjake2/client/Console.java
+++ b/src/lwjake2/client/Console.java
@@ -25,7 +25,8 @@ import lwjake2.game.Cmd;
 import lwjake2.qcommon.Cbuf;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.util.Lib;
 import lwjake2.util.Vargs;
 
@@ -38,6 +39,7 @@ import java.util.Arrays;
  */
 @Slf4j
 public final class Console extends Globals {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
     public static Runnable ToggleConsole_f = new Runnable() {
         public void run() {
             SCR.EndLoadingPlaque(); // get rid of loading plaque
@@ -93,10 +95,10 @@ public final class Console extends Globals {
 
             //Com_sprintf (name, sizeof(name), "%s/%s.txt", FS_Gamedir(),
             // Cmd_Argv(1));
-            name = FS.Gamedir() + "/" + Cmd.Argv(1) + ".txt";
+            name = fileSystem.getGamedir() + "/" + Cmd.Argv(1) + ".txt";
 
             log.info("Dumped console text to {}", name);
-            FS.CreatePath(name);
+            fileSystem.createPath(name);
             f = Lib.fopen(name, "rw");
             if (f == null) {
                 log.error("ERROR: couldn't open.");
diff --git a/src/lwjake2/client/Menu.java b/src/lwjake2/client/Menu.java
index 723f31c..42210cb 100644
--- a/src/lwjake2/client/Menu.java
+++ b/src/lwjake2/client/Menu.java
@@ -24,7 +24,8 @@ import lwjake2.game.cvar_t;
 import lwjake2.qcommon.Cbuf;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.netadr_t;
 import lwjake2.sound.S;
 import lwjake2.sys.NET;
@@ -33,6 +34,8 @@ import lwjake2.sys.Timer;
 import lwjake2.util.Lib;
 import lwjake2.util.Math3D;
 import lwjake2.util.QuakeFile;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.awt.Dimension;
 import java.io.RandomAccessFile;
@@ -50,6 +53,8 @@ abstract class keyfunc_t {
 }
 
 public final class Menu extends Key {
+    private static final Logger logger = LoggerFactory.getLogger(Menu.class);
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
     static int m_main_cursor;
 
@@ -1885,9 +1890,6 @@ public final class Menu extends Key {
     public static String Credits_Key(int key) {
         switch (key) {
         case K_ESCAPE:
-            if (creditsBuffer != null)
-                //FS.FreeFile(creditsBuffer);
-                ;
             PopMenu();
             break;
         }
@@ -1906,7 +1908,7 @@ public final class Menu extends Key {
         int n;
         int isdeveloper = 0;
 
-        byte b[] = FS.LoadFile("credits");
+        byte b[] = fileSystem.loadFile("credits");
 
         if (b != null) {
             creditsBuffer = new String(b);
@@ -1919,7 +1921,7 @@ public final class Menu extends Key {
             creditsIndex[n] = null;
             credits = creditsIndex;
         } else {
-            isdeveloper = FS.Developer_searchpath(1);
+            isdeveloper = fileSystem.developer_searchpath(1);
 
             if (isdeveloper == 1) // xatrix
                 credits = xatcredits;
@@ -2167,7 +2169,7 @@ public final class Menu extends Key {
         for (i = 0; i < MAX_SAVEGAMES; i++) {
 
             m_savestrings[i] = "<EMPTY>";
-            name = FS.Gamedir() + "/save/save" + i + "/server.ssv";
+            name = fileSystem.getGamedir() + "/save/save" + i + "/server.ssv";
 
             try {
                 f = new QuakeFile(name, "r");
@@ -2589,7 +2591,7 @@ public final class Menu extends Key {
         //	  =====
         //	  PGM
         // ROGUE GAMES
-        else if (FS.Developer_searchpath(2) == 2) {
+        else if (fileSystem.developer_searchpath(2) == 2) {
             if (s_rules_box.curvalue == 2) // tag
             {
                 s_maxclients_field.statusbar = null;
@@ -2635,7 +2637,7 @@ public final class Menu extends Key {
         //		Cvar.SetValue ("coop", s_rules_box.curvalue );
 
         //	  PGM
-        if ((s_rules_box.curvalue < 2) || (FS.Developer_searchpath(2) != 2)) {
+        if ((s_rules_box.curvalue < 2) || (fileSystem.developer_searchpath(2) != 2)) {
             Cvar.SetValue("deathmatch", 1 - (int) (s_rules_box.curvalue));
             Cvar.SetValue("coop", s_rules_box.curvalue);
             Cvar.SetValue("gamerules", 0);
@@ -2699,15 +2701,15 @@ public final class Menu extends Key {
         /*
          * * load the list of map names
          */
-        mapsname = FS.Gamedir() + "/maps.lst";
+        mapsname = fileSystem.getGamedir() + "/maps.lst";
 
         // Check user dir first (default ~/.lwjake2)
         if ((fp = Lib.fopen(mapsname, "r")) == null) {
         	// Check base dir first (baseq2 folder)
-        	mapsname = FS.BaseGamedir() + "/maps.lst";
+        	mapsname = fileSystem.getBaseGamedir() + "/maps.lst";
         	if ((fp = Lib.fopen(mapsname, "r")) == null) {
         		// Open the pak's maplist
-	            buffer = FS.LoadFile("maps.lst");
+	            buffer = fileSystem.loadFile("maps.lst");
 	            if (buffer == null)
 	                Com.Error(ERR_DROP, "couldn't find maps.lst\n");
         	} else {
@@ -2755,7 +2757,7 @@ public final class Menu extends Key {
             fp = null;
 
         } else {
-            FS.FreeFile(buffer);
+            buffer = null;
         }
 
         /*
@@ -2776,7 +2778,7 @@ public final class Menu extends Key {
         s_rules_box.name = "rules";
 
         //	  PGM - rogue games only available with rogue DLL.
-        if (FS.Developer_searchpath(2) == 2)
+        if (fileSystem.developer_searchpath(2) == 2)
             s_rules_box.itemnames = dm_coop_names_rogue;
         else
             s_rules_box.itemnames = dm_coop_names;
@@ -3059,7 +3061,7 @@ public final class Menu extends Key {
 
         //	  =======
         //	  ROGUE
-        else if (FS.Developer_searchpath(2) == 2) {
+        else if (fileSystem.developer_searchpath(2) == 2) {
             if (f == s_no_mines_box) {
                 bit = DF_NO_MINES;
             } else if (f == s_no_nukes_box) {
@@ -3283,7 +3285,7 @@ public final class Menu extends Key {
 
         //	  ============
         //	  ROGUE
-        if (FS.Developer_searchpath(2) == 2) {
+        if (fileSystem.developer_searchpath(2) == 2) {
             s_no_mines_box.type = MTYPE_SPINCONTROL;
             s_no_mines_box.x = 0;
             s_no_mines_box.y = y += 10;
@@ -3354,7 +3356,7 @@ public final class Menu extends Key {
 
         //	  =======
         //	  ROGUE
-        if (FS.Developer_searchpath(2) == 2) {
+        if (fileSystem.developer_searchpath(2) == 2) {
             Menu_AddItem(s_dmoptions_menu, s_no_mines_box);
             Menu_AddItem(s_dmoptions_menu, s_no_nukes_box);
             Menu_AddItem(s_dmoptions_menu, s_stack_double_box);
@@ -3764,10 +3766,10 @@ public final class Menu extends Key {
          * * get a list of directories
          */
         do {
-            path = FS.NextPath(path);
+            path = fileSystem.nextPath(path);
             findname = path + "/players/*.*";
 
-            if ((dirnames = FS.ListFiles(findname, 0, SFF_SUBDIR)) != null) {
+            if ((dirnames = fileSystem.listFiles(findname, 0, SFF_SUBDIR)) != null) {
                 ndirs = dirnames.length;
                 break;
             }
@@ -3807,7 +3809,7 @@ public final class Menu extends Key {
 
             // verify the existence of at least one pcx skin
             scratch = dirnames[i] + "/*.pcx";
-            pcxnames = FS.ListFiles(scratch, 0, 0);
+            pcxnames = fileSystem.listFiles(scratch, 0, 0);
             npcxfiles = pcxnames.length;
 
             // count valid skins, which consist of a skin with a matching "_i"
diff --git a/src/lwjake2/client/SCR.java b/src/lwjake2/client/SCR.java
index 74796e7..0f9d1c1 100644
--- a/src/lwjake2/client/SCR.java
+++ b/src/lwjake2/client/SCR.java
@@ -23,12 +23,7 @@ import lwjake2.Defines;
 import lwjake2.Globals;
 import lwjake2.game.Cmd;
 import lwjake2.game.cvar_t;
-import lwjake2.qcommon.Com;
-import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
-import lwjake2.qcommon.MSG;
-import lwjake2.qcommon.SZ;
-import lwjake2.qcommon.qfiles;
+import lwjake2.qcommon.*;
 import lwjake2.sound.S;
 import lwjake2.sys.Timer;
 import lwjake2.util.Lib;
@@ -44,6 +39,7 @@ import java.util.Arrays;
  */
 @Slf4j
 public final class SCR extends Globals {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
     //	cl_scrn.c -- master for refresh, status bar, console, chat, notify, etc
 
     static String[][] sb_nums = {
@@ -1392,7 +1388,7 @@ public final class SCR extends Globals {
         qfiles.pcx_t pcx;
 
         // load the file
-        ByteBuffer raw = FS.LoadMappedFile(filename);
+        ByteBuffer raw = fileSystem.loadMappedFile(filename);
 
         if (raw == null) {
             VID.Printf(Defines.PRINT_DEVELOPER, "Bad pcx file " + filename
@@ -1831,7 +1827,7 @@ public final class SCR extends Globals {
         }
 
         String name = "video/" + arg;
-        cl.cinematic_file = FS.LoadMappedFile(name);
+        cl.cinematic_file = fileSystem.loadMappedFile(name);
         if (cl.cinematic_file == null) {
             //Com.Error(ERR_DROP, "Cinematic " + name + " not found.\n");
             FinishCinematic();
diff --git a/src/lwjake2/client/V.java b/src/lwjake2/client/V.java
index bfb085b..eb7e82f 100644
--- a/src/lwjake2/client/V.java
+++ b/src/lwjake2/client/V.java
@@ -384,6 +384,7 @@ public final class V extends Globals {
                     (int) cl.refdef.vieworg[1],
                     (int) cl.refdef.vieworg[2],
                     (int) cl.refdef.viewangles[YAW]
+            );
         }
     };
 
diff --git a/src/lwjake2/game/Cmd.java b/src/lwjake2/game/Cmd.java
index ce5b7f1..cac93d8 100644
--- a/src/lwjake2/game/Cmd.java
+++ b/src/lwjake2/game/Cmd.java
@@ -22,13 +22,7 @@ import lombok.extern.slf4j.Slf4j;
 import lwjake2.Defines;
 import lwjake2.Globals;
 import lwjake2.game.monsters.M_Player;
-import lwjake2.qcommon.Cbuf;
-import lwjake2.qcommon.Com;
-import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
-import lwjake2.qcommon.MSG;
-import lwjake2.qcommon.SZ;
-import lwjake2.qcommon.cmd_function_t;
+import lwjake2.qcommon.*;
 import lwjake2.server.SV_GAME;
 import lwjake2.util.Lib;
 
@@ -41,6 +35,7 @@ import java.util.Vector;
  */
 @Slf4j
 public final class Cmd {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
     static Runnable List_f = new Runnable() {
         public void run() {
             cmd_function_t cmd = Cmd.cmd_functions;
@@ -63,7 +58,7 @@ public final class Cmd {
             }
 
             byte[] f = null;
-            f = FS.LoadFile(Cmd.Argv(1));
+            f = fileSystem.loadFile(Cmd.Argv(1));
             if (f == null) {
                 log.info("couldn't exec {}", Cmd.Argv(1));
                 return;
@@ -71,8 +66,6 @@ public final class Cmd {
             log.info("execing {}", Cmd.Argv(1));
 
             Cbuf.InsertText(new String(f));
-
-            FS.FreeFile(f);
         }
     };
 
@@ -386,7 +379,7 @@ public final class Cmd {
     /**
      * Cmd_ExecuteString
      * 
-     * A complete command line has been parsed, so try to run it
+     * A complete command line has been parsed, so try to execute it 
      * FIXME: lookupnoadd the token to speed search? 
      */
     public static void ExecuteString(String text) {
@@ -396,7 +389,7 @@ public final class Cmd {
 
         TokenizeString(text.toCharArray(), true);
 
-        // run the command line
+        // execute the command line
         if (Argc() == 0)
             return; // no tokens
 
diff --git a/src/lwjake2/qcommon/FS.java b/src/lwjake2/qcommon/BaseQ2FileSystem.java
similarity index 78%
rename from src/lwjake2/qcommon/FS.java
rename to src/lwjake2/qcommon/BaseQ2FileSystem.java
index 5d1f15f..7fcfd3f 100644
--- a/src/lwjake2/qcommon/FS.java
+++ b/src/lwjake2/qcommon/BaseQ2FileSystem.java
@@ -28,7 +28,6 @@ import lwjake2.sys.Sys;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.RandomAccessFile;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
@@ -38,80 +37,81 @@ import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 
-/**
- * FS
- * 
+import static lwjake2.Defines.*;
+
+/*
+ * ==================================================
+ *
+ * QUAKE FILESYSTEM
+ *
  * @author cwei
+ * @author DmitriyMX <dimon550@gmail.com>
+ * @modify 2018-03-06
+ *
+ * ==================================================
  */
+
 @Slf4j
-public final class FS extends Globals {
-    /*
-     * ==================================================
-     * 
-     * QUAKE FILESYSTEM
-     * 
-     * ==================================================
-     */
+public class BaseQ2FileSystem implements FileSystem {
+    private static final BaseQ2FileSystem instance = new BaseQ2FileSystem();
+    private static final int IDPAKHEADER = (('K' << 24) + ('C' << 16) + ('A' << 8) + 'P');
+    private static final int MAX_FILES_IN_PACK = 4096;
+    // read in blocks of 64k
+    private static final int MAX_READ = 0x10000;
 
-    public static class packfile_t {
+    public static BaseQ2FileSystem getInstance() {
+        return instance;
+    }
+
+    private BaseQ2FileSystem() {}
+
+    private static class packfile_t {
         static final int SIZE = 64;
-
         static final int NAME_SIZE = 56;
-
         String name; // char name[56]
-
         int filepos, filelen;
-
         public String toString() {
             return name + " [ length: " + filelen + " pos: " + filepos + " ]";
         }
     }
 
-    public static class pack_t {
+    private static class pack_t {
         String filename;
-
         RandomAccessFile handle;
-        
         ByteBuffer backbuffer;
-
         int numfiles;
-
         Hashtable<String, packfile_t> files; // with packfile_t entries
     }
 
-    public static String fs_gamedir;
+    private String fs_gamedir;
 
-    private static String fs_userdir;
+    private String fs_userdir;
 
-    public static cvar_t fs_basedir;
+    private cvar_t fs_basedir;
 
-    public static cvar_t fs_cddir;
+    private cvar_t fs_cddir;
 
-    public static cvar_t fs_gamedirvar;
+    private cvar_t fs_gamedirvar;
 
-    public static class filelink_t {
+    private static class filelink_t {
         String from;
-
         int fromlength;
-
         String to;
     }
 
     // with filelink_t entries
-    public static List<filelink_t> fs_links = new LinkedList<filelink_t>();
+    private List<filelink_t> fs_links = new LinkedList<>();
 
-    public static class searchpath_t {
+    private static class searchpath_t {
         String filename;
-
         pack_t pack; // only one of filename or pack will be used
-
         searchpath_t next;
     }
 
-    public static searchpath_t fs_searchpaths;
+    private searchpath_t fs_searchpaths;
 
     // without gamedirs
-    public static searchpath_t fs_base_searchpaths;
+    private searchpath_t fs_base_searchpaths;
 
     /*
      * All of Quake's data access is through a hierchal file system, but the
@@ -135,10 +135,11 @@ public final class FS extends Globals {
 
     /*
      * CreatePath
-     * 
+     *
      * Creates any directories needed to store the given filename.
      */
-    public static void CreatePath(String path) {
+    @Override
+    public void createPath(String path) {
         int index = path.lastIndexOf('/');
         // -1 if not found and 0 means write to root
         if (index > 0) {
@@ -149,32 +150,16 @@ public final class FS extends Globals {
         }
     }
 
-    /*
-     * FCloseFile
-     * 
-     * For some reason, other dll's can't just call fclose() on files returned
-     * by FS_FOpenFile...
-     */
-    public static void FCloseFile(RandomAccessFile file) throws IOException {
-        file.close();
-    }
-
-    public static void FCloseFile(InputStream stream) throws IOException {
-        stream.close();
-    }
-
-    public static int FileLength(String filename) {
+    @Override
+    public int fileLength(String filename) {
         searchpath_t search;
         String netpath;
         pack_t pak;
-        filelink_t link;
 
         file_from_pak = 0;
 
         // check for links first
-        for (Iterator<filelink_t> it = fs_links.iterator(); it.hasNext();) {
-            link = it.next();
-
+        for (filelink_t link : fs_links) {
             if (filename.regionMatches(0, link.from, 0, link.fromlength)) {
                 netpath = link.to + filename.substring(link.fromlength);
                 File file = new File(netpath);
@@ -226,28 +211,25 @@ public final class FS extends Globals {
         return -1;
     }
 
-    public static int file_from_pak = 0;
+    private int file_from_pak = 0;
 
     /*
      * FOpenFile
-     * 
+     *
      * Finds the file in the search path. returns a RadomAccesFile. Used for
      * streaming data out of either a pak file or a seperate file.
      */
-    public static RandomAccessFile FOpenFile(String filename)
-            throws IOException {
+    @Override
+    public RandomAccessFile FOpenFile(String filename) throws IOException {
         searchpath_t search;
         String netpath;
         pack_t pak;
-        filelink_t link;
-        File file = null;
+        File file;
 
         file_from_pak = 0;
 
         // check for links first
-        for (Iterator<filelink_t> it = fs_links.iterator(); it.hasNext();) {
-            link = it.next();
-
+        for (filelink_t link : fs_links) {
             //			if (!strncmp (filename, link->from, link->fromlength))
             if (filename.regionMatches(0, link.from, 0, link.fromlength)) {
                 netpath = link.to + filename.substring(link.fromlength);
@@ -308,19 +290,16 @@ public final class FS extends Globals {
         return null;
     }
 
-    // read in blocks of 64k
-    public static final int MAX_READ = 0x10000;
-
     /**
      * Read
-     * 
+     *
      * Properly handles partial reads
      */
-    public static void Read(byte[] buffer, int len, RandomAccessFile f) {
-
+    @Override
+    public void read(byte[] buffer, int len, RandomAccessFile file) {
         int block, remaining;
         int offset = 0;
-        int read = 0;
+        int read;
 
         // read in chunks for progress bar
         remaining = len;
@@ -328,15 +307,18 @@ public final class FS extends Globals {
         while (remaining != 0) {
             block = Math.min(remaining, MAX_READ);
             try {
-                read = f.read(buffer, offset, block);
+                read = file.read(buffer, offset, block);
             } catch (IOException e) {
-                Com.Error(Defines.ERR_FATAL, e.toString());
+                log.error(e.toString());
+                throw new RuntimeException("Look log file");
             }
 
             if (read == 0) {
-                Com.Error(Defines.ERR_FATAL, "FS_Read: 0 bytes read");
+                log.error("FS_Read: 0 bytes read");
+                throw new RuntimeException("Look log file");
             } else if (read == -1) {
-                Com.Error(Defines.ERR_FATAL, "FS_Read: -1 bytes read");
+                log.error("FS_Read: -1 bytes read");
+                throw new RuntimeException("Look log file");
             }
             //
             // do some progress bar thing here...
@@ -348,15 +330,16 @@ public final class FS extends Globals {
 
     /*
      * LoadFile
-     * 
+     *
      * Filename are reletive to the quake search path a null buffer will just
      * return the file content as byte[]
      */
-    public static byte[] LoadFile(String path) {
+    @Override
+    public byte[] loadFile(String path) {
         RandomAccessFile file;
 
         byte[] buf = null;
-        int len = 0;
+        int len;
 
         // TODO hack for bad strings (fuck \0)
         int index = path.indexOf('\0');
@@ -364,7 +347,7 @@ public final class FS extends Globals {
             path = path.substring(0, index);
 
         // look for it in the filesystem or pack files
-        len = FileLength(path);
+        len = fileLength(path);
 
         if (len < 1)
             return null;
@@ -373,6 +356,7 @@ public final class FS extends Globals {
             file = FOpenFile(path);
             //Read(buf = new byte[len], len, h);
             buf = new byte[len];
+            assert file != null;
             file.readFully(buf);
             file.close();
         } catch (IOException e) {
@@ -383,29 +367,27 @@ public final class FS extends Globals {
 
     /*
      * LoadMappedFile
-     * 
+     *
      * Filename are reletive to the quake search path a null buffer will just
      * return the file content as ByteBuffer (memory mapped)
      */
-    public static ByteBuffer LoadMappedFile(String filename) {
+    @Override
+    public ByteBuffer loadMappedFile(String filename) {
         searchpath_t search;
         String netpath;
         pack_t pak;
-        filelink_t link;
-        File file = null;
+        File file;
 
-        int fileLength = 0;
+        int fileLength;
         FileChannel channel = null;
         FileInputStream input = null;
-        ByteBuffer buffer = null;
+        ByteBuffer buffer;
 
         file_from_pak = 0;
 
         try {
             // check for links first
-            for (Iterator<filelink_t> it = fs_links.iterator(); it.hasNext();) {
-                link = it.next();
-
+            for (filelink_t link : fs_links) {
                 if (filename.regionMatches(0, link.from, 0, link.fromlength)) {
                     netpath = link.to + filename.substring(link.fromlength);
                     file = new File(netpath);
@@ -477,66 +459,52 @@ public final class FS extends Globals {
                     return buffer;
                 }
             }
-        } catch (Exception e) {
+        } catch (Exception ignored) {
         }
         try {
             if (input != null)
                 input.close();
             else if (channel != null && channel.isOpen())
                 channel.close();
-        } catch (IOException ioe) {
+        } catch (IOException ignored) {
         }
         return null;
     }
 
-    /*
-     * FreeFile
-     */
-    public static void FreeFile(byte[] buffer) {
-        buffer = null;
-    }
-
-    static final int IDPAKHEADER = (('K' << 24) + ('C' << 16) + ('A' << 8) + 'P');
-
-    static class dpackheader_t {
+    private static class dpackheader_t {
         int ident; // IDPAKHEADER
-
         int dirofs;
-
         int dirlen;
     }
 
-    static final int MAX_FILES_IN_PACK = 4096;
-
     // buffer for C-Strings char[56]
-    static byte[] tmpText = new byte[packfile_t.NAME_SIZE];
+    private byte[] tmpText = new byte[packfile_t.NAME_SIZE];
 
     /*
      * LoadPackFile
-     * 
+     *
      * Takes an explicit (not game tree related) path to a pak file.
-     * 
+     *
      * Loads the header and directory, adding the files at the beginning of the
      * list so they override previous pack files.
      */
-    static pack_t LoadPackFile(String packfile) {
-
+    private pack_t loadPackFile(String packfile) {
         dpackheader_t header;
         Hashtable<String, packfile_t> newfiles;
         RandomAccessFile file;
-        int numpackfiles = 0;
-        pack_t pack = null;
+        int numpackfiles;
+        pack_t pack;
         //		unsigned checksum;
         //
         try {
-        	file = new RandomAccessFile(packfile, "r");
-        	FileChannel fc = file.getChannel();
+            file = new RandomAccessFile(packfile, "r");
+            FileChannel fc = file.getChannel();
             ByteBuffer packhandle = fc.map(FileChannel.MapMode.READ_ONLY, 0, file.length());
             packhandle.order(ByteOrder.LITTLE_ENDIAN);
- 
+
             fc.close();
-            
-            if (packhandle == null || packhandle.limit() < 1)
+
+            if (packhandle.limit() < 1)
                 return null;
             //
             header = new dpackheader_t();
@@ -553,12 +521,12 @@ public final class FS extends Globals {
                 Com.Error(Defines.ERR_FATAL, packfile + " has " + numpackfiles
                         + " files");
 
-            newfiles = new Hashtable<String, packfile_t>(numpackfiles);
+            newfiles = new Hashtable<>(numpackfiles);
 
             packhandle.position(header.dirofs);
 
             // parse the directory
-            packfile_t entry = null;
+            packfile_t entry;
 
             for (int i = 0; i < numpackfiles; i++) {
                 packhandle.get(tmpText);
@@ -577,7 +545,7 @@ public final class FS extends Globals {
         }
 
         pack = new pack_t();
-        pack.filename = new String(packfile);
+        pack.filename = packfile;
         pack.handle = file;
         pack.numfiles = numpackfiles;
         pack.files = newfiles;
@@ -589,23 +557,23 @@ public final class FS extends Globals {
 
     /*
      * AddGameDirectory
-     * 
+     *
      * Sets fs_gamedir, adds the directory to the head of the path, then loads
      * and adds pak1.pak pak2.pak ...
      */
-    static void AddGameDirectory(String dir) {
+    private void addGameDirectory(String dir) {
         int i;
         searchpath_t search;
         pack_t pak;
         String pakfile;
 
-        fs_gamedir = new String(dir);
+        fs_gamedir = dir;
 
         //
         // add the directory to the search path
         // ensure fs_userdir is first in searchpath
         search = new searchpath_t();
-        search.filename = new String(dir);
+        search.filename = dir;
         if (fs_searchpaths != null) {
             search.next = fs_searchpaths.next;
             fs_searchpaths.next = search;
@@ -621,7 +589,7 @@ public final class FS extends Globals {
             if (!(new File(pakfile).canRead()))
                 continue;
 
-            pak = LoadPackFile(pakfile);
+            pak = loadPackFile(pakfile);
             if (pak == null)
                 continue;
 
@@ -639,7 +607,8 @@ public final class FS extends Globals {
      * Called to find where to write a file (demos, savegames, etc)
      * this is modified to <user.home>/.lwjake2 
      */
-    public static String Gamedir() {
+    @Override
+    public String getGamedir() {
         return (fs_userdir != null) ? fs_userdir : Globals.BASEDIRNAME;
     }
 
@@ -648,14 +617,16 @@ public final class FS extends Globals {
      * 
      * Called to find where to write a downloaded file
      */
-    public static String BaseGamedir() {
+    @Override
+    public String getBaseGamedir() {
         return (fs_gamedir != null) ? fs_gamedir : Globals.BASEDIRNAME;
     }
 
     /*
      * ExecAutoexec
      */
-    public static void ExecAutoexec() {
+    @Override
+    public void execAutoexec() {
         String dir = fs_userdir;
 
         String name;
@@ -676,14 +647,14 @@ public final class FS extends Globals {
 
     /*
      * SetGamedir
-     * 
+     *
      * Sets the gamedir and path to a different directory.
      */
-    public static void SetGamedir(String dir) {
+    @Override
+    public void setGamedir(String dir) {
         searchpath_t next;
 
-        if (dir.indexOf("..") != -1 || dir.indexOf("/") != -1
-                || dir.indexOf("\\") != -1 || dir.indexOf(":") != -1) {
+        if (dir.contains("..") || dir.contains("/") || dir.contains("\\") || dir.contains(":")) {
             log.warn("Gamedir should be a single filename, not a path");
             return;
         }
@@ -704,7 +675,6 @@ public final class FS extends Globals {
                 fs_searchpaths.pack = null;
             }
             next = fs_searchpaths.next;
-            fs_searchpaths = null;
             fs_searchpaths = next;
         }
 
@@ -722,9 +692,9 @@ public final class FS extends Globals {
         } else {
             Cvar.FullSet("gamedir", dir, CVAR_SERVERINFO | CVAR_NOSET);
             if (fs_cddir.string != null && fs_cddir.string.length() > 0)
-                AddGameDirectory(fs_cddir.string + '/' + dir);
+                addGameDirectory(fs_cddir.string + '/' + dir);
 
-            AddGameDirectory(fs_basedir.string + '/' + dir);
+            addGameDirectory(fs_basedir.string + '/' + dir);
         }
     }
 
@@ -733,8 +703,8 @@ public final class FS extends Globals {
      * 
      * Creates a filelink_t
      */
-    public static void Link_f() {
-        filelink_t entry = null;
+    private void link_f() {
+        filelink_t entry;
 
         if (Cmd.Argc() != 3) {
             log.info("USAGE: link <from> <to>");
@@ -751,7 +721,7 @@ public final class FS extends Globals {
                     it.remove();
                     return;
                 }
-                entry.to = new String(Cmd.Argv(2));
+                entry.to = Cmd.Argv(2);
                 return;
             }
         }
@@ -759,9 +729,9 @@ public final class FS extends Globals {
         // create a new link if the <to> is not empty
         if (Cmd.Argv(2).length() > 0) {
             entry = new filelink_t();
-            entry.from = new String(Cmd.Argv(1));
+            entry.from = Cmd.Argv(1);
             entry.fromlength = entry.from.length();
-            entry.to = new String(Cmd.Argv(2));
+            entry.to = Cmd.Argv(2);
             fs_links.add(entry);
         }
     }
@@ -769,7 +739,8 @@ public final class FS extends Globals {
     /*
      * ListFiles
      */
-    public static String[] ListFiles(String findname, int musthave, int canthave) {
+    @Override
+    public String[] listFiles(String findname, int musthave, int canthave) {
         String[] list = new String[0];
 
         File[] files = Sys.FindAll(findname, musthave, canthave);
@@ -787,9 +758,9 @@ public final class FS extends Globals {
     /*
      * Dir_f
      */
-    public static void Dir_f() {
+    private void dir_f() {
         String path = null;
-        String findname = null;
+        String findname;
         String wildcard = "*.*";
         String[] dirnames;
 
@@ -797,26 +768,21 @@ public final class FS extends Globals {
             wildcard = Cmd.Argv(1);
         }
 
-        while ((path = NextPath(path)) != null) {
-            String tmp = findname;
-
+        while ((path = nextPath(path)) != null) {
             findname = path + '/' + wildcard;
 
-            if (tmp != null)
-                tmp.replaceAll("\\\\", "/");
-
             log.info("Directory of {}", findname);
             log.info("----");
 
-            dirnames = ListFiles(findname, 0, 0);
+            dirnames = listFiles(findname, 0, 0);
 
             if (dirnames.length != 0) {
-                int index = 0;
-                for (int i = 0; i < dirnames.length; i++) {
-                    if ((index = dirnames[i].lastIndexOf('/')) > 0) {
-                        log.info(dirnames[i].substring(index + 1, dirnames[i].length()));
+                int index;
+                for (String dirname : dirnames) {
+                    if ((index = dirname.lastIndexOf('/')) > 0) {
+                        log.info(dirname.substring(index + 1, dirname.length()));
                     } else {
-                        log.info(dirnames[i]);
+                        log.info(dirname);
                     }
                 }
             }
@@ -827,10 +793,8 @@ public final class FS extends Globals {
     /*
      * Path_f
      */
-    public static void Path_f() {
-
+    private void path_f() {
         searchpath_t s;
-        filelink_t link;
 
         log.info("Current search path:");
         for (s = fs_searchpaths; s != null; s = s.next) {
@@ -843,18 +807,18 @@ public final class FS extends Globals {
         }
 
         log.info("Links:");
-        for (Iterator<filelink_t> it = fs_links.iterator(); it.hasNext();) {
-            link = it.next();
+        for (filelink_t link : fs_links) {
             log.info("{} : {}", link.from, link.to);
         }
     }
 
     /*
      * NextPath
-     * 
+     *
      * Allows enumerating all of the directories in the search path
      */
-    public static String NextPath(String prevpath) {
+    @Override
+    public String nextPath(String prevpath) {
         searchpath_t s;
         String prev;
 
@@ -866,7 +830,7 @@ public final class FS extends Globals {
             if (s.pack != null)
                 continue;
 
-            if (prevpath == prev)
+            if (prevpath.equals(prev))
                 return s.filename;
 
             prev = s.filename;
@@ -878,26 +842,15 @@ public final class FS extends Globals {
     /*
      * InitFilesystem
      */
-    public static void InitFilesystem() {
-        Cmd.AddCommand("path", new Runnable() {
-            public void run() {
-                Path_f();
-            }
-        });
-        Cmd.AddCommand("link", new Runnable() {
-            public void run() {
-                Link_f();
-            }
-        });
-        Cmd.AddCommand("dir", new Runnable() {
-            public void run() {
-                Dir_f();
-            }
-        });
+    @Override
+    public void init() {
+        Cmd.AddCommand("path", this::path_f);
+        Cmd.AddCommand("link", this::link_f);
+        Cmd.AddCommand("dir", this::dir_f);
 
         fs_userdir = System.getProperty("user.home") + "/.lwjake2";
-        FS.CreatePath(fs_userdir + "/");
-        FS.AddGameDirectory(fs_userdir);
+        createPath(fs_userdir + "/");
+        addGameDirectory(fs_userdir);
 
         //
         // basedir <path>
@@ -916,7 +869,7 @@ public final class FS extends Globals {
         //
         // start up with baseq2 by default
         //
-        AddGameDirectory(fs_basedir.string + '/' + Globals.BASEDIRNAME);
+        addGameDirectory(fs_basedir.string + '/' + Globals.BASEDIRNAME);
 
         // any set gamedirs will be freed up to here
         markBaseSearchPaths();
@@ -928,21 +881,27 @@ public final class FS extends Globals {
     /**
      * set baseq2 directory
      */
-    static void setCDDir() {
+    @Override
+    public void setCDDir() {
         fs_cddir = Cvar.Get("cddir", "", CVAR_ARCHIVE);
-        if (fs_cddir.string.length() > 0)
-            AddGameDirectory(fs_cddir.string + '/' + Globals.BASEDIRNAME);
+        if (fs_cddir != null && fs_cddir.string.length() > 0)
+            addGameDirectory(fs_cddir.string + '/' + Globals.BASEDIRNAME);
     }
-    
-    /** Check for "+set game" override - Used to properly set gamedir */
-    static void checkOverride() {
-    	fs_gamedirvar = Cvar.Get("game", "", CVAR_LATCH | CVAR_SERVERINFO);
 
-        if (fs_gamedirvar.string.length() > 0)
-            SetGamedir(fs_gamedirvar.string);
+    /**
+     * Check for "+set game" override - Used to properly set gamedir
+     */
+    @Override
+    public void checkOverride() {
+        fs_gamedirvar = Cvar.Get("game", "", CVAR_LATCH | CVAR_SERVERINFO);
+
+        if (fs_gamedirvar != null && fs_gamedirvar.string.length() > 0) {
+            setGamedir(fs_gamedirvar.string);
+        }
     }
-    
-    static void markBaseSearchPaths() {
+
+    @Override
+    public void markBaseSearchPaths() {
         // any set gamedirs will be freed up to here
         fs_base_searchpaths = fs_searchpaths;
     }
@@ -951,21 +910,30 @@ public final class FS extends Globals {
     /*
      * Developer_searchpath
      */
-    public static int Developer_searchpath(int who) {
-
+    @Override
+    public int developer_searchpath(int who) {
         // PMM - warning removal
         //	 char *start;
         searchpath_t s;
 
-        
         for (s = fs_searchpaths; s != null; s = s.next) {
-            if (s.filename.indexOf("xatrix") != -1)
+            if (s.filename.contains("xatrix"))
                 return 1;
 
-            if (s.filename.indexOf("rogue") != -1)
+            if (s.filename.contains("rogue"))
                 return 2;
         }
 
         return 0;
     }
+
+    @Override
+    public int getFileFromPak() {
+        return file_from_pak;
+    }
+
+    @Override
+    public cvar_t getGamedirVar() {
+        return fs_gamedirvar;
+    }
 }
\ No newline at end of file
diff --git a/src/lwjake2/qcommon/CM.java b/src/lwjake2/qcommon/CM.java
index 875ab25..8cbc237 100644
--- a/src/lwjake2/qcommon/CM.java
+++ b/src/lwjake2/qcommon/CM.java
@@ -37,6 +37,7 @@ import java.nio.IntBuffer;
 import java.util.Arrays;
 
 public class CM {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
     public static class cnode_t {
         cplane_t plane; // ptr
@@ -248,7 +249,7 @@ public class CM {
         //
         // load the file
         //
-        buf = FS.LoadFile(name);
+        buf = fileSystem.loadFile(name);
 
         if (buf == null)
             Com.Error(Defines.ERR_DROP, "Couldn't load " + name);
@@ -283,8 +284,6 @@ public class CM {
         CMod_LoadAreaPortals(header.lumps[Defines.LUMP_AREAPORTALS]);       
         CMod_LoadVisibility(header.lumps[Defines.LUMP_VISIBILITY]);
         CMod_LoadEntityString(header.lumps[Defines.LUMP_ENTITIES]);
-        
-        FS.FreeFile(buf);
 
         CM_InitBoxHull();
 
@@ -1787,7 +1786,7 @@ public class CM {
 
         byte buf[] = new byte[len];
 
-        FS.Read(buf, len, f);
+        fileSystem.read(buf, len, f);
 
         ByteBuffer bb = ByteBuffer.wrap(buf);
         IntBuffer ib = bb.asIntBuffer();
diff --git a/src/lwjake2/qcommon/Cbuf.java b/src/lwjake2/qcommon/Cbuf.java
index 54ddffd..fd43582 100644
--- a/src/lwjake2/qcommon/Cbuf.java
+++ b/src/lwjake2/qcommon/Cbuf.java
@@ -189,7 +189,7 @@ public final class Cbuf {
 
             }
 
-            // run the command line
+            // execute the command line
             int len = Lib.strlen(line);
 
             String cmd = new String(line, 0, len);
diff --git a/src/lwjake2/qcommon/Cvar.java b/src/lwjake2/qcommon/Cvar.java
index 7944334..3f13727 100644
--- a/src/lwjake2/qcommon/Cvar.java
+++ b/src/lwjake2/qcommon/Cvar.java
@@ -33,6 +33,7 @@ import java.util.Vector;
  * Cvar implements console variables. The original code is located in cvar.c
  */
 public class Cvar extends Globals {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
     /**
      * @param var_name
@@ -194,8 +195,8 @@ public class Cvar extends Globals {
                         var.value = 0.0f;
                     }
                     if (var.name.equals("game")) {
-                        FS.SetGamedir(var.string);
-                        FS.ExecAutoexec();
+                        fileSystem.setGamedir(var.string);
+                        fileSystem.execAutoexec();
                     }
                 }
                 return var;
@@ -384,8 +385,8 @@ public class Cvar extends Globals {
                 var.value = 0.0f;
             }
             if (var.name.equals("game")) {
-                FS.SetGamedir(var.string);
-                FS.ExecAutoexec();
+                fileSystem.setGamedir(var.string);
+                fileSystem.execAutoexec();
             }
         }
     }
diff --git a/src/lwjake2/qcommon/FileSystem.java b/src/lwjake2/qcommon/FileSystem.java
new file mode 100644
index 0000000..e46f8de
--- /dev/null
+++ b/src/lwjake2/qcommon/FileSystem.java
@@ -0,0 +1,37 @@
+/*
+ * DmitriyMX <dimon550@gmail.com>
+ * 2018-03-06
+ */
+package lwjake2.qcommon;
+
+import lwjake2.game.cvar_t;
+
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.ByteBuffer;
+
+public interface FileSystem {
+    void init();
+    byte[] loadFile(String path);
+    void read(byte[] buffer, int len, RandomAccessFile file);
+    void execAutoexec();
+    void createPath(String path);
+    int fileLength(String filename);
+    String nextPath(String prevpath);
+    String[] listFiles(String findname, int musthave, int canthave);
+
+    int developer_searchpath(int who);
+    cvar_t getGamedirVar();
+
+    void setGamedir(String dir);
+    String getGamedir();
+
+    String getBaseGamedir();
+
+    ByteBuffer loadMappedFile(String filename);
+    void setCDDir();
+    void markBaseSearchPaths();
+    void checkOverride();
+    RandomAccessFile FOpenFile(String filename) throws IOException;
+    int getFileFromPak();
+}
diff --git a/src/lwjake2/qcommon/Qcommon.java b/src/lwjake2/qcommon/Qcommon.java
index caa84e1..299d59d 100644
--- a/src/lwjake2/qcommon/Qcommon.java
+++ b/src/lwjake2/qcommon/Qcommon.java
@@ -39,6 +39,7 @@ import java.io.IOException;
  */
 @Slf4j
 public final class Qcommon extends Globals {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	public static final String BUILDSTRING = "Java " + System.getProperty("java.version");;
 	public static final String CPUSTRING = System.getProperty("os.arch");
 
@@ -69,13 +70,13 @@ public final class Qcommon extends Globals {
 			Cbuf.AddEarlyCommands(false);
 			Cbuf.Execute();
 			
-			FS.InitFilesystem();
+			fileSystem.init();
 			
 			reconfigure(false);
 
-			FS.setCDDir(); // use cddir from config.cfg
-			FS.markBaseSearchPaths(); // mark the default search paths
-			FS.checkOverride();
+			fileSystem.setCDDir(); // use cddir from config.cfg
+			fileSystem.markBaseSearchPaths(); // mark the default search paths
+			fileSystem.checkOverride();
 			
 			reconfigure(true); // reload default.cfg and config.cfg
 			
diff --git a/src/lwjake2/render/DummyRenderer.java b/src/lwjake2/render/DummyRenderer.java
index 2440752..72511eb 100644
--- a/src/lwjake2/render/DummyRenderer.java
+++ b/src/lwjake2/render/DummyRenderer.java
@@ -163,7 +163,7 @@ public class DummyRenderer implements refexport_t {
 	}
 
 	/* (non-Javadoc)
-	 * @see jake2.client.refexport_t#updateScreen(jake2.qcommon.Runnable)
+	 * @see jake2.client.refexport_t#updateScreen(java.lang.Runnable)
 	 */
 	public void updateScreen(Runnable callback) {
 	    callback.run();
diff --git a/src/lwjake2/render/lwjgl/Image.java b/src/lwjake2/render/lwjgl/Image.java
index 0374fd7..ef4c20e 100644
--- a/src/lwjake2/render/lwjgl/Image.java
+++ b/src/lwjake2/render/lwjgl/Image.java
@@ -22,10 +22,7 @@ import lwjake2.Defines;
 import lwjake2.client.VID;
 import lwjake2.client.particle_t;
 import lwjake2.game.cvar_t;
-import lwjake2.qcommon.Com;
-import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
-import lwjake2.qcommon.qfiles;
+import lwjake2.qcommon.*;
 import lwjake2.render.image_t;
 import lwjake2.util.Lib;
 import lwjake2.util.Vargs;
@@ -51,6 +48,7 @@ import org.lwjgl.opengl.GL11;
  * @author cwei
  */
 public abstract class Image extends Main {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
 	image_t draw_chars;
 
@@ -450,7 +448,7 @@ public abstract class Image extends Main {
 		//
 		// load the file
 		//
-		byte[] raw = FS.LoadFile(filename);
+		byte[] raw = fileSystem.loadFile(filename);
 
 		if (raw == null) {
 			VID.Printf(Defines.PRINT_DEVELOPER, "Bad pcx file " + filename + '\n');
@@ -547,7 +545,7 @@ public abstract class Image extends Main {
 		//
 		// load the file
 		//
-		raw = FS.LoadFile(name);
+		raw = fileSystem.loadFile(name);
 		
 		if (raw == null)
 		{
@@ -1446,7 +1444,7 @@ public abstract class Image extends Main {
 
 		image_t image = null;
 
-		byte[] raw = FS.LoadFile(name);
+		byte[] raw = fileSystem.loadFile(name);
 		if (raw == null) {
 			VID.Printf(Defines.PRINT_ALL, "GL_FindImage: can't load " + name + '\n');
 			return r_notexture;
@@ -1630,7 +1628,7 @@ public abstract class Image extends Main {
 		Draw_GetPalette();
 
 		if (qglColorTableEXT) {
-			gl_state.d_16to8table = FS.LoadFile("pics/16to8.dat");
+			gl_state.d_16to8table = fileSystem.loadFile("pics/16to8.dat");
 			if (gl_state.d_16to8table == null)
 				Com.Error(Defines.ERR_FATAL, "Couldn't load pics/16to8.pcx");
 		}
diff --git a/src/lwjake2/render/lwjgl/Misc.java b/src/lwjake2/render/lwjgl/Misc.java
index cd32bd7..c78e385 100644
--- a/src/lwjake2/render/lwjgl/Misc.java
+++ b/src/lwjake2/render/lwjgl/Misc.java
@@ -20,7 +20,7 @@ package lwjake2.render.lwjgl;
 
 import lwjake2.Defines;
 import lwjake2.client.VID;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.BaseQ2FileSystem;
 
 import java.io.File;
 import java.io.IOException;
@@ -29,6 +29,7 @@ import java.nio.FloatBuffer;
 import java.nio.MappedByteBuffer;
 import java.nio.channels.FileChannel;
 
+import lwjake2.qcommon.FileSystem;
 import org.lwjgl.BufferUtils;
 import org.lwjgl.opengl.ARBMultitexture;
 import org.lwjgl.opengl.EXTPointParameters;
@@ -42,6 +43,7 @@ import org.lwjgl.opengl.GL12;
  * @author cwei
  */
 public abstract class Misc extends Mesh {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
 	/*
 	==================
@@ -121,8 +123,8 @@ public abstract class Misc extends Mesh {
 	================== 
 	*/  
 	void GL_ScreenShot_f() {
-	    StringBuffer sb = new StringBuffer(FS.Gamedir() + "/scrshot/jake00.tga");
-	    FS.CreatePath(sb.toString());
+	    StringBuffer sb = new StringBuffer(fileSystem.getGamedir() + "/scrshot/jake00.tga");
+	    fileSystem.createPath(sb.toString());
 	    File file = new File(sb.toString());
 	    // find a valid file name
 	    int i = 0; int offset = sb.length() - 6;
diff --git a/src/lwjake2/render/lwjgl/Model.java b/src/lwjake2/render/lwjgl/Model.java
index c1f01eb..4a7e410 100644
--- a/src/lwjake2/render/lwjgl/Model.java
+++ b/src/lwjake2/render/lwjgl/Model.java
@@ -24,7 +24,8 @@ import lwjake2.game.cplane_t;
 import lwjake2.game.cvar_t;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.lump_t;
 import lwjake2.qcommon.qfiles;
 import lwjake2.qcommon.texinfo_t;
@@ -54,6 +55,7 @@ import org.lwjgl.BufferUtils;
  * @author cwei
  */
 public abstract class Model extends Surf {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	
 	// models.c -- model loading and caching
 
@@ -271,7 +273,7 @@ public abstract class Model extends Surf {
 		//
 		// load the file
 		//
-		fileBuffer = FS.LoadFile(name);
+		fileBuffer = fileSystem.loadFile(name);
 
 		if (fileBuffer == null)
 		{
diff --git a/src/lwjake2/server/SV_CCMDS.java b/src/lwjake2/server/SV_CCMDS.java
index fbbb684..9c8019d 100644
--- a/src/lwjake2/server/SV_CCMDS.java
+++ b/src/lwjake2/server/SV_CCMDS.java
@@ -30,7 +30,8 @@ import lwjake2.game.cvar_t;
 import lwjake2.qcommon.CM;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.MSG;
 import lwjake2.qcommon.Netchan;
 import lwjake2.qcommon.SZ;
@@ -50,6 +51,7 @@ import java.util.Calendar;
 
 @Slf4j
 public class SV_CCMDS {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	/*
 	===============================================================================
 	
@@ -176,13 +178,13 @@ public class SV_CCMDS {
 
 		Com.DPrintf("SV_WipeSaveGame(" + savename + ")\n");
 
-		name = FS.Gamedir() + "/save/" + savename + "/server.ssv";
+		name = fileSystem.getGamedir() + "/save/" + savename + "/server.ssv";
 		remove(name);
 
-		name = FS.Gamedir() + "/save/" + savename + "/game.ssv";
+		name = fileSystem.getGamedir() + "/save/" + savename + "/game.ssv";
 		remove(name);
 
-		name = FS.Gamedir() + "/save/" + savename + "/*.sav";
+		name = fileSystem.getGamedir() + "/save/" + savename + "/*.sav";
 
 		File f = Sys.FindFirst(name, 0, 0);
 		while (f != null) {
@@ -191,7 +193,7 @@ public class SV_CCMDS {
 		}
 		Sys.FindClose();
 
-		name = FS.Gamedir() + "/save/" + savename + "/*.sv2";
+		name = fileSystem.getGamedir() + "/save/" + savename + "/*.sv2";
 
 		f = Sys.FindFirst(name, 0, 0);
 
@@ -281,23 +283,23 @@ public class SV_CCMDS {
 		SV_WipeSavegame(dst);
 
 		// copy the savegame over
-		name = FS.Gamedir() + "/save/" + src + "/server.ssv";
-		name2 = FS.Gamedir() + "/save/" + dst + "/server.ssv";
-		FS.CreatePath(name2);
+		name = fileSystem.getGamedir() + "/save/" + src + "/server.ssv";
+		name2 = fileSystem.getGamedir() + "/save/" + dst + "/server.ssv";
+		fileSystem.createPath(name2);
 		CopyFile(name, name2);
 
-		name = FS.Gamedir() + "/save/" + src + "/game.ssv";
-		name2 = FS.Gamedir() + "/save/" + dst + "/game.ssv";
+		name = fileSystem.getGamedir() + "/save/" + src + "/game.ssv";
+		name2 = fileSystem.getGamedir() + "/save/" + dst + "/game.ssv";
 		CopyFile(name, name2);
 
-		String name1 = FS.Gamedir() + "/save/" + src + "/";
-		name = FS.Gamedir() + "/save/" + src + "/*.sav";
+		String name1 = fileSystem.getGamedir() + "/save/" + src + "/";
+		name = fileSystem.getGamedir() + "/save/" + src + "/*.sav";
 
 		found = Sys.FindFirst(name, 0, 0);
 
 		while (found != null) {
 			name = name1 + found.getName();
-			name2 = FS.Gamedir() + "/save/" + dst + "/" + found.getName();
+			name2 = fileSystem.getGamedir() + "/save/" + dst + "/" + found.getName();
 
 			CopyFile(name, name2);
 
@@ -324,7 +326,7 @@ public class SV_CCMDS {
 
 		Com.DPrintf("SV_WriteLevelFile()\n");
 
-		name = FS.Gamedir() + "/save/current/" + SV_INIT.sv.name + ".sv2";
+		name = fileSystem.getGamedir() + "/save/current/" + SV_INIT.sv.name + ".sv2";
 
 		try {
 			f = new QuakeFile(name, "rw");
@@ -340,7 +342,7 @@ public class SV_CCMDS {
 			e.printStackTrace();
 		}
 
-		name = FS.Gamedir() + "/save/current/" + SV_INIT.sv.name + ".sav";
+		name = fileSystem.getGamedir() + "/save/current/" + SV_INIT.sv.name + ".sav";
 		GameSave.WriteLevel(name);
 	}
 	/*
@@ -356,7 +358,7 @@ public class SV_CCMDS {
 
 		Com.DPrintf("SV_ReadLevelFile()\n");
 
-		name = FS.Gamedir() + "/save/current/" + SV_INIT.sv.name + ".sv2";
+		name = fileSystem.getGamedir() + "/save/current/" + SV_INIT.sv.name + ".sv2";
 		try {
 			f = new QuakeFile(name, "r");
 
@@ -372,7 +374,7 @@ public class SV_CCMDS {
 			e1.printStackTrace();
 		}
 
-		name = FS.Gamedir() + "/save/current/" + SV_INIT.sv.name + ".sav";
+		name = fileSystem.getGamedir() + "/save/current/" + SV_INIT.sv.name + ".sav";
 		GameSave.ReadLevel(name);
 	}
 	/*
@@ -389,7 +391,7 @@ public class SV_CCMDS {
 
 		Com.DPrintf("SV_WriteServerFile(" + (autosave ? "true" : "false") + ")\n");
 
-		filename = FS.Gamedir() + "/save/current/server.ssv";
+		filename = fileSystem.getGamedir() + "/save/current/server.ssv";
 		try {
 			f = new QuakeFile(filename, "rw");
 
@@ -442,7 +444,7 @@ public class SV_CCMDS {
 		}
 
 		// write game state
-		filename = FS.Gamedir() + "/save/current/game.ssv";
+		filename = fileSystem.getGamedir() + "/save/current/game.ssv";
 		GameSave.WriteGame(filename, autosave);
 	}
 	/*
@@ -460,7 +462,7 @@ public class SV_CCMDS {
 
 			Com.DPrintf("SV_ReadServerFile()\n");
 
-			filename = FS.Gamedir() + "/save/current/server.ssv";
+			filename = fileSystem.getGamedir() + "/save/current/server.ssv";
 
 			f = new QuakeFile(filename, "r");
 
@@ -487,7 +489,7 @@ public class SV_CCMDS {
 			SV_INIT.svs.mapcmd = mapcmd;
 
 			// read game state
-			filename = FS.Gamedir() + "/save/current/game.ssv";
+			filename = fileSystem.getGamedir() + "/save/current/game.ssv";
 			GameSave.ReadGame(filename);
 		}
 		catch (Exception e) {
@@ -538,7 +540,7 @@ public class SV_CCMDS {
 
 		Com.DPrintf("SV_GameMap(" + Cmd.Argv(1) + ")\n");
 
-		FS.CreatePath(FS.Gamedir() + "/save/current/");
+		fileSystem.createPath(fileSystem.getGamedir() + "/save/current/");
 
 		// check for clearing the current savegame
 		map = Cmd.Argv(1);
@@ -599,7 +601,7 @@ public class SV_CCMDS {
 		map = Cmd.Argv(1);
 		if (map.indexOf(".") < 0) {
 			expanded = "maps/" + map + ".bsp";
-			if (FS.LoadFile(expanded) == null) {
+			if (fileSystem.loadFile(expanded) == null) {
 
 				Com.Printf("Can't find " + expanded + "\n");
 				return;
@@ -644,7 +646,7 @@ public class SV_CCMDS {
 		}
 
 		// make sure the server.ssv file exists
-		name = FS.Gamedir() + "/save/" + Cmd.Argv(1) + "/server.ssv";
+		name = fileSystem.getGamedir() + "/save/" + Cmd.Argv(1) + "/server.ssv";
 		try {
 			f = new RandomAccessFile(name, "r");
 		}
@@ -913,10 +915,10 @@ public class SV_CCMDS {
 		//
 		// open the demo file
 		//
-		name = FS.Gamedir() + "/demos/" + Cmd.Argv(1) + ".dm2";
+		name = fileSystem.getGamedir() + "/demos/" + Cmd.Argv(1) + ".dm2";
 
 		Com.Printf("recording to " + name + ".\n");
-		FS.CreatePath(name);
+		fileSystem.createPath(name);
 		try {
 			SV_INIT.svs.demofile = new RandomAccessFile(name, "rw");
 		}
diff --git a/src/lwjake2/server/SV_INIT.java b/src/lwjake2/server/SV_INIT.java
index 613109b..fa1da8a 100644
--- a/src/lwjake2/server/SV_INIT.java
+++ b/src/lwjake2/server/SV_INIT.java
@@ -32,7 +32,8 @@ import lwjake2.qcommon.CM;
 import lwjake2.qcommon.Cbuf;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.MSG;
 import lwjake2.qcommon.PMove;
 import lwjake2.qcommon.SZ;
@@ -45,6 +46,7 @@ import java.io.RandomAccessFile;
 
 @Slf4j
 public class SV_INIT {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
     /**
      * SV_FindIndex.
      */
@@ -134,7 +136,7 @@ public class SV_INIT {
         if (Cvar.VariableValue("deathmatch") != 0)
             return;
 
-        name = FS.Gamedir() + "/save/current/" + sv.name + ".sav";
+        name = fileSystem.getGamedir() + "/save/current/" + sv.name + ".sav";
         try {
             f = new RandomAccessFile(name, "r");
         }
diff --git a/src/lwjake2/server/SV_MAIN.java b/src/lwjake2/server/SV_MAIN.java
index 69d1928..3755a51 100644
--- a/src/lwjake2/server/SV_MAIN.java
+++ b/src/lwjake2/server/SV_MAIN.java
@@ -29,7 +29,6 @@ import lwjake2.game.cvar_t;
 import lwjake2.game.edict_t;
 import lwjake2.qcommon.Com;
 import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
 import lwjake2.qcommon.MSG;
 import lwjake2.qcommon.Netchan;
 import lwjake2.qcommon.SZ;
@@ -116,7 +115,6 @@ public class SV_MAIN {
         }
 
         if (drop.download != null) {
-            FS.FreeFile(drop.download);
             drop.download = null;
         }
 
diff --git a/src/lwjake2/server/SV_USER.java b/src/lwjake2/server/SV_USER.java
index 61cef8c..2c1287e 100644
--- a/src/lwjake2/server/SV_USER.java
+++ b/src/lwjake2/server/SV_USER.java
@@ -27,17 +27,13 @@ import lwjake2.game.PlayerClient;
 import lwjake2.game.edict_t;
 import lwjake2.game.entity_state_t;
 import lwjake2.game.usercmd_t;
-import lwjake2.qcommon.Cbuf;
-import lwjake2.qcommon.Com;
-import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
-import lwjake2.qcommon.MSG;
-import lwjake2.qcommon.SZ;
+import lwjake2.qcommon.*;
 import lwjake2.util.Lib;
 
 import java.io.IOException;
 
 public class SV_USER {
+    private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 
     static edict_t sv_player;
 
@@ -120,7 +116,7 @@ public class SV_USER {
 
         name = "demos/" + SV_INIT.sv.name;
         try {
-            SV_INIT.sv.demofile = FS.FOpenFile(name);
+            SV_INIT.sv.demofile = fileSystem.FOpenFile(name);
         } catch (IOException e) {
             Com.Error(Defines.ERR_DROP, "Couldn't open " + name + "\n");
         }
@@ -365,7 +361,6 @@ public class SV_USER {
         if (SV_MAIN.sv_client.downloadcount != SV_MAIN.sv_client.downloadsize)
             return;
 
-        FS.FreeFile(SV_MAIN.sv_client.download);
         SV_MAIN.sv_client.download = null;
     }
 
@@ -409,9 +404,9 @@ public class SV_USER {
         }
 
         if (SV_MAIN.sv_client.download != null)
-            FS.FreeFile(SV_MAIN.sv_client.download);
+            SV_MAIN.sv_client.download = null;
 
-        SV_MAIN.sv_client.download = FS.LoadFile(name);
+        SV_MAIN.sv_client.download = fileSystem.loadFile(name);
         
         // rst: this handles loading errors, no message yet visible 
         if (SV_MAIN.sv_client.download == null)
@@ -429,11 +424,10 @@ public class SV_USER {
                                                // came from a pak file, don't
                                                // allow
                 							   // download ZOID
-                || (name.startsWith("maps/") && FS.file_from_pak != 0)) {
+                || (name.startsWith("maps/") && fileSystem.getFileFromPak() != 0)) {
             Com.DPrintf("Couldn't download " + name + " to "
                     + SV_MAIN.sv_client.name + "\n");
             if (SV_MAIN.sv_client.download != null) {
-                FS.FreeFile(SV_MAIN.sv_client.download);
                 SV_MAIN.sv_client.download = null;
             }
 
diff --git a/src/lwjake2/sound/WaveLoader.java b/src/lwjake2/sound/WaveLoader.java
index 50e56ab..cca5b1d 100644
--- a/src/lwjake2/sound/WaveLoader.java
+++ b/src/lwjake2/sound/WaveLoader.java
@@ -20,14 +20,16 @@ package lwjake2.sound;
 
 import lombok.extern.slf4j.Slf4j;
 import lwjake2.Defines;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.Com;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
 
 /**
  * SND_MEM
  */
 @Slf4j
 public class WaveLoader {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	/** 
 	 * The ResampleSfx can squeeze and stretch samples to a default sample rate. 
 	 * Since Joal and lwjgl sound drivers support this, we don't need it and the samples
@@ -66,7 +68,7 @@ public class WaveLoader {
 		else
 			namebuffer = "sound/" + name;
 
-		byte[] data = FS.LoadFile(namebuffer);
+		byte[] data = fileSystem.loadFile(namebuffer);
 
 		if (data == null) {
 			Com.DPrintf("Couldn't load " + namebuffer + "\n");
diff --git a/src/lwjake2/sound/lwjgl/LWJGLSoundImpl.java b/src/lwjake2/sound/lwjgl/LWJGLSoundImpl.java
index 473dec2..44eb8b7 100644
--- a/src/lwjake2/sound/lwjgl/LWJGLSoundImpl.java
+++ b/src/lwjake2/sound/lwjgl/LWJGLSoundImpl.java
@@ -25,9 +25,7 @@ import lwjake2.game.Cmd;
 import lwjake2.game.GameBase;
 import lwjake2.game.cvar_t;
 import lwjake2.game.entity_state_t;
-import lwjake2.qcommon.Com;
-import lwjake2.qcommon.Cvar;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.*;
 import lwjake2.sound.S;
 import lwjake2.sound.Sound;
 import lwjake2.sound.WaveLoader;
@@ -57,6 +55,7 @@ import org.lwjgl.openal.OpenALException;
  */
 @Slf4j
 public final class LWJGLSoundImpl implements Sound {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	static {
 		S.register(new LWJGLSoundImpl());
 	};
@@ -379,14 +378,14 @@ public final class LWJGLSoundImpl implements Sound {
 		// fall back strategies
 		//
 		// not found , so see if it exists
-		if (FS.FileLength(sexedFilename.substring(1)) > 0) {
+		if (fileSystem.fileLength(sexedFilename.substring(1)) > 0) {
 			// yes, register it
 			return RegisterSound(sexedFilename);
 		}
 	    // try it with the female sound in the pak0.pak
 		if (model.equalsIgnoreCase("female")) {
 			String femaleFilename = "player/female/" + base.substring(1);
-			if (FS.FileLength("sound/" + femaleFilename) > 0)
+			if (fileSystem.fileLength("sound/" + femaleFilename) > 0)
 			    return AliasName(sexedFilename, femaleFilename);
 		}
 		// no chance, revert to the male sound in the pak0.pak
diff --git a/src/lwjake2/util/Lib.java b/src/lwjake2/util/Lib.java
index 5bba8b3..9ec91be 100644
--- a/src/lwjake2/util/Lib.java
+++ b/src/lwjake2/util/Lib.java
@@ -20,8 +20,9 @@ package lwjake2.util;
 
 import lombok.extern.slf4j.Slf4j;
 import lwjake2.Globals;
+import lwjake2.qcommon.BaseQ2FileSystem;
 import lwjake2.qcommon.Com;
-import lwjake2.qcommon.FS;
+import lwjake2.qcommon.FileSystem;
 
 import java.io.File;
 import java.io.IOException;
@@ -34,6 +35,7 @@ import java.nio.IntBuffer;
 
 @Slf4j
 public class Lib {
+	private static final FileSystem fileSystem = BaseQ2FileSystem.getInstance();
 	/** Converts a vector to a string. */
 	public static String vtos(float[] v) {
 		return (int) v[0] + " " + (int) v[1] + " " + (int) v[2];
@@ -240,7 +242,7 @@ public class Lib {
 	/** Like in libc */
 	public static String freadString(RandomAccessFile f, int len) {
 		byte buffer[] = new byte[len];
-		FS.Read(buffer, len, f);
+		fileSystem.read(buffer, len, f);
 	
 		return Lib.CtoJava(buffer);
 	}