diff --git a/src/main/java/bigfilecreator/BigFileCreator.java b/src/main/java/bigfilecreator/BigFileCreator.java
index 9da8231..9dae244 100644
--- a/src/main/java/bigfilecreator/BigFileCreator.java
+++ b/src/main/java/bigfilecreator/BigFileCreator.java
@@ -10,7 +10,6 @@
 import javafx.beans.value.ObservableValue;
 import javafx.collections.ObservableList;
 import javafx.event.ActionEvent;
-import javafx.event.EventHandler;
 import javafx.scene.Node;
 import javafx.scene.Scene;
 import javafx.scene.control.Button;
@@ -93,7 +92,7 @@ public void start(Stage primaryStage)
         
         //Line 14.
         gb.add(null, 2);
-        gb.add(new Button("Buduj Plik"));
+        gb.add(new Button("Buduj plik"));
         gb.add(new Text());
         
         gb.add(new Text(), 4);
@@ -134,7 +133,7 @@ public void start(Stage primaryStage)
         tf.focusedProperty().addListener
         (
             (ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) ->
-            { NameValidator.isWrong((boolean)newValue, (TextField)tfList.get(0), (Text)tList.get(1), (Text)tList.get(2), (TextField)tfList.get(1), fs); }
+                    NameValidator.isWrong(newValue, (TextField)tfList.get(0), (Text)tList.get(1), (Text)tList.get(2), (TextField)tfList.get(1), fs)
         );
         
         //Path-----------------------------
@@ -174,7 +173,7 @@ public void start(Stage primaryStage)
         tf.focusedProperty().addListener
         (
             (ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) ->
-            { SizeValidator.isWrong((boolean)newValue, (TextField)tfList.get(2), (Text)tList.get(7)); }
+                    SizeValidator.isWrong(newValue, (TextField)tfList.get(2), (Text)tList.get(7))
         );
         
         //Structure-----------------------------
@@ -203,11 +202,11 @@ public void start(Stage primaryStage)
             (ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) ->
             {
                 TextField temp;
-                StructureValidator.isWrong((boolean)newValue, (TextField)tfList.get(3), (Text)tList.get(8), (Text)tList.get(10), (Text)tList.get(9), fs);
+                StructureValidator.isWrong(newValue, (TextField)tfList.get(3), (Text)tList.get(8), (Text)tList.get(10), (Text)tList.get(9), fs);
                 temp = (TextField)tfList.get(4);
-                if(fs.getStatesCount() > 0 && !temp.getText().equals("")) { StateValidator.isWrong((boolean)newValue, temp, (Text)tList.get(11), (Text)tList.get(13), (Text)tList.get(12), fs); }
+                if(fs.getStatesCount() > 0 && !temp.getText().equals("")) { StateValidator.isWrong(newValue, temp, (Text)tList.get(11), (Text)tList.get(13), (Text)tList.get(12), fs); }
                 temp = (TextField)tfList.get(5);
-                if(!temp.getText().equals("")) { HeaderValidator.isWrong((boolean)newValue, temp, (Text)tList.get(14), (Text)tList.get(16), (Text)tList.get(15), fs); }
+                if(!temp.getText().equals("")) { HeaderValidator.isWrong(newValue, temp, (Text)tList.get(14), (Text)tList.get(16), (Text)tList.get(15), fs); }
             }
         );
         
@@ -234,7 +233,7 @@ public void start(Stage primaryStage)
         tf.focusedProperty().addListener
         (
             (ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) ->
-            { StateValidator.isWrong((boolean)newValue, (TextField)tfList.get(4), (Text)tList.get(11), (Text)tList.get(13), (Text)tList.get(12), fs); }
+                    StateValidator.isWrong(newValue, (TextField)tfList.get(4), (Text)tList.get(11), (Text)tList.get(13), (Text)tList.get(12), fs)
         );
         
         //Header-----------------------------
@@ -262,7 +261,7 @@ public void start(Stage primaryStage)
             (ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) ->
             {
                 TextField temp = (TextField)tfList.get(5);
-                if(!temp.getText().equals("")) { HeaderValidator.isWrong((boolean)newValue, temp, (Text)tList.get(14), (Text)tList.get(16), (Text)tList.get(15), fs); }
+                if(!temp.getText().equals("")) { HeaderValidator.isWrong(newValue, temp, (Text)tList.get(14), (Text)tList.get(16), (Text)tList.get(15), fs); }
             }
         );
         
@@ -274,29 +273,24 @@ public void start(Stage primaryStage)
         btn.setDisable(true);
         btn.setMaxWidth(minWidthMainCol);
         
-        btn.setOnAction(new EventHandler<ActionEvent>()
-        {
-            @Override
-            public void handle(ActionEvent e)
+        btn.setOnAction(e -> {
+            if(!fs.isReady())
             {
-                if(!fs.isReady())
-                {
-                    ((Text)tList.get(17)).setText("");
-                    ((Text)tList.get(18)).setText("Nie można zbudować pliku, wypełnij poprawnie wszystkie pola.");
-                }
-                else
-                {
-                    ((Text)tList.get(17)).setText("");
-                    ((Text)tList.get(18)).setText("");
-                    
-                    String path = fs.getAllName();
-                    File file = new File(path);
-                    if(file.exists()) { file.delete(); }
-                    Writter t1 = new Writter(fs);
-                    WritterGUI t2 = new WritterGUI(fs, (Text)tList.get(17), btnList, tfList);
-                    t1.start();
-                    t2.start();
-                }
+                ((Text)tList.get(17)).setText("");
+                ((Text)tList.get(18)).setText("Nie można zbudować pliku, wypełnij poprawnie wszystkie pola.");
+            }
+            else
+            {
+                ((Text)tList.get(17)).setText("");
+                ((Text)tList.get(18)).setText("");
+
+                String path = fs.getAllName();
+                File file = new File(path);
+                if(file.exists()) { file.delete(); }
+                Writer t1 = new Writer(fs);
+                WriterGUI t2 = new WriterGUI(fs, (Text)tList.get(17), btnList, tfList);
+                t1.start();
+                t2.start();
             }
         });
         
diff --git a/src/main/java/bigfilecreator/GridBuilder.java b/src/main/java/bigfilecreator/GridBuilder.java
index b5cc0e2..0224e5f 100644
--- a/src/main/java/bigfilecreator/GridBuilder.java
+++ b/src/main/java/bigfilecreator/GridBuilder.java
@@ -25,12 +25,12 @@ public void add(Node child)
         if(child != null) { grid.add(child, p.c, p.v); }
     }
     
-    public void add(Node child, int colspan)
+    public void add(Node child, int colSpan)
     {
         Position p = pc.nextPosition();
 
-        if(child != null) { grid.add(child, p.c, p.v, colspan, 1); }
-        for(int i=0 ; i<colspan-1 ; i++) { pc.nextPosition(); }
+        if(child != null) { grid.add(child, p.c, p.v, colSpan, 1); }
+        for(int i=0 ; i<colSpan-1 ; i++) { pc.nextPosition(); }
     }
     
     public GridPane getGrid() { return grid; }
diff --git a/src/main/java/bigfilecreator/Validate/ValidateSettings.java b/src/main/java/bigfilecreator/Validate/ValidateSettings.java
index 260eeca..7234be4 100644
--- a/src/main/java/bigfilecreator/Validate/ValidateSettings.java
+++ b/src/main/java/bigfilecreator/Validate/ValidateSettings.java
@@ -1,6 +1,5 @@
 package bigfilecreator.Validate;
 
-import bigfilecreator.FileSettings;
 import java.io.File;
 import java.util.Scanner;
 import java.util.regex.Matcher;
@@ -9,7 +8,6 @@
 public class ValidateSettings
 {
     public static final int maxNameLength = 35;
-    private static Scanner scan;
 
     private static final String namePtrnStr = "(.+)[.](.+)";
     
@@ -116,7 +114,7 @@ public static double checkDouble(String value)
         {
             try
             {
-                scan = new Scanner(value);
+                Scanner scan = new Scanner(value);
                 size = scan.nextDouble();
             }
             catch(Exception ex2) { return Double.NEGATIVE_INFINITY; }
@@ -149,7 +147,6 @@ public static boolean checkState(String value)
         if(value == null) { return false; }
         value = value.trim();
         Matcher m = statePtrn.matcher(value);
-        if(!m.find()) { return false; }
-        return true;
+        return m.find();
     }
 }
\ No newline at end of file
diff --git a/src/main/java/bigfilecreator/Writter.java b/src/main/java/bigfilecreator/Writer.java
similarity index 71%
rename from src/main/java/bigfilecreator/Writter.java
rename to src/main/java/bigfilecreator/Writer.java
index 116c177..0b59447 100644
--- a/src/main/java/bigfilecreator/Writter.java
+++ b/src/main/java/bigfilecreator/Writer.java
@@ -8,11 +8,11 @@
 import java.sql.Timestamp;
 import java.util.ArrayList;
 
-public class Writter extends Thread
+public class Writer extends Thread
 {
-    final FileSettings fs;
+    private final FileSettings fs;
     
-    public Writter(FileSettings settings) { this.fs = settings; }
+    public Writer(FileSettings settings) { this.fs = settings; }
         
     @Override
     public void run()
@@ -30,7 +30,7 @@ public void run()
                 delimiter = "\t";
                 structure = structure.replace(" t ", " \t ");
             }
-            String[] splittedArray = structure.split(delimiter);
+            String[] splitArray = structure.split(delimiter);
                     
             String type, toWrite = fs.getHeader().replace(" t ", " \t ");
             if(toWrite.length() > 0) { writer.println(toWrite); }
@@ -42,11 +42,9 @@ public void run()
             while(currentSize < size)
             {
                 toWrite = "";
-                for(int i=0 ; i<splittedArray.length ; i++)
-                {
-                    type = splittedArray[i].trim();
-                    switch(type)
-                    {
+                for (String aSplitArray : splitArray) {
+                    type = aSplitArray.trim();
+                    switch (type) {
                         case "boolean":
                             toWrite += rand.nextBoolean() + delimiter;
                             break;
@@ -54,47 +52,40 @@ public void run()
                         case "int":
                             toWrite += rand.nextInt() + delimiter;
                             break;
-                            
+
                         case "long":
                             toWrite += rand.nextLong() + delimiter;
                             break;
 
-                        case "float":
-                        {
-                            float f=1;
+                        case "float": {
+                            float f = 1;
                             long pow = rand.nextInt(38);
-                            for(int j=0 ; j<pow ; j++) { f *= 10L; }
+                            for (int j = 0; j < pow; j++) {
+                                f *= 10L;
+                            }
                             f *= rand.nextFloat();
                             toWrite += f + delimiter;
                             break;
                         }
 
-                        case "double":
-                        {
-                            double d=1;
+                        case "double": {
+                            double d = 1;
                             long pow = rand.nextInt(308);
-                            for(int j=0 ; j<pow ; j++) { d *= 10L; }
+                            for (int j = 0; j < pow; j++) {
+                                d *= 10L;
+                            }
                             d *= rand.nextDouble();
                             toWrite += d + delimiter;
                             break;
                         }
 
                         case "string":
-                        case "String":
-                        {
+                        case "String": {
                             String s = "";
                             int len = rand.nextInt(20) + 1;
                             char c;
-                            int k;
                             String alpha = "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
-                            if(false) for(int j=0 ; j<len ; j++)
-                            {
-                                do { c = (char)rand.nextInt(65525); }
-                                while(c == fs.getDelimiter());
-                                s += c;
-                            }
-                            else for(int j=0 ; j<len ; j++)
-                            {
+                            for (int j = 0; j < len; j++) {
                                 c = alpha.charAt(rand.nextInt(52));
                                 s += c;
                             }
@@ -103,17 +94,15 @@ public void run()
                         }
 
                         case "timestamp":
-                        case "Timestamp":
-                        {
-                             //1900-01-01 00:00:00.0 -> 2100-12-31 23:59:59.999999999
+                        case "Timestamp": {
+                            //1900-01-01 00:00:00.0 -> 2100-12-31 23:59:59.999999999
                             Timestamp tmp = new Timestamp(rand.nextInt(201), rand.nextInt(12), rand.nextInt(29), rand.nextInt(24), rand.nextInt(60), rand.nextInt(60), rand.nextInt(1000000000));
-                            Timestamp t = new Timestamp(tmp.getTime() + rand.nextInt(4)*86400000);
+                            Timestamp t = new Timestamp(tmp.getTime() + rand.nextInt(4) * 86400000);
                             toWrite += t.toString().substring(0, 16) + delimiter;
                             break;
                         }
-                        
-                        case "state":
-                        {
+
+                        case "state": {
                             ArrayList<String> temp = states.get(stateIt);
                             toWrite += temp.get(rand.nextInt(temp.size())) + delimiter;
                             stateIt++;
@@ -121,7 +110,9 @@ public void run()
                             break;
                         }
 
-                        default: { break; }
+                        default: {
+                            break;
+                        }
                     }
                 }
                 writer.println(toWrite.substring(0, toWrite.length()-1));
diff --git a/src/main/java/bigfilecreator/WritterGUI.java b/src/main/java/bigfilecreator/WriterGUI.java
similarity index 83%
rename from src/main/java/bigfilecreator/WritterGUI.java
rename to src/main/java/bigfilecreator/WriterGUI.java
index 1ac4574..66a904f 100644
--- a/src/main/java/bigfilecreator/WritterGUI.java
+++ b/src/main/java/bigfilecreator/WriterGUI.java
@@ -5,14 +5,14 @@
 import javafx.scene.Node;
 import javafx.scene.text.Text;
 
-public class WritterGUI extends Thread
+public class WriterGUI extends Thread
 {
     private final Text status;
     private final ObservableList<Node> btnList;
     private final ObservableList<Node> tfList;
     private final FileSettings fs;
 
-    public WritterGUI(FileSettings settings, Text status, ObservableList<Node> btnList, ObservableList<Node> tfList)
+    public WriterGUI(FileSettings settings, Text status, ObservableList<Node> btnList, ObservableList<Node> tfList)
     {
         this.fs = settings;
         this.status = status;
@@ -24,7 +24,7 @@ public WritterGUI(FileSettings settings, Text status, ObservableList<Node> btnLi
     public void run()
     {
         ObservableList<Node> temp;
-        temp = tfList.filtered(tf -> tf.isDisabled() == false);
+        temp = tfList.filtered(tf -> !tf.isDisabled());
         temp.forEach(tf -> tf.setDisable(true));
         btnList.forEach(b -> b.setDisable(true));