diff --git a/FileParser.java b/FileParser.java
new file mode 100644
index 0000000..ac53737
--- /dev/null
+++ b/FileParser.java
@@ -0,0 +1,27 @@
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * File parser.
+ */
+public interface FileParser {
+  /**
+   * Return current file.
+   * @return Current file
+   */
+  File file();
+
+  /**
+   * Return content.
+   * @return Content
+   * @throws IOException if something is wrong
+   */
+  String content() throws IOException;
+
+  /**
+   * Save content.
+   * @param Content to save
+   * @throws IOException if something went wrong
+   */
+  void saveContent(final String content) throws IOException;
+}
diff --git a/Parser.java b/Parser.java
index d6d65d3..14dc187 100644
--- a/Parser.java
+++ b/Parser.java
@@ -5,38 +5,27 @@
 /**
  * This class is thread safe.
  */
-public class Parser {
-  private File file;
-  public synchronized void setFile(File f) {
-    file = f;
+public class Parser implements FileParser {
+  private final File file;
+  public Parser(final File file) {
+      this.file = file;
   }
-  public synchronized File getFile() {
-    return file;
-  }
-  public String getContent() throws IOException {
-    FileInputStream i = new FileInputStream(file);
-    String output = "";
-    int data;
-    while ((data = i.read()) > 0) {
-      output += (char) data;
+  public synchronized File file() {
+        return file;
     }
-    return output;
-  }
-  public String getContentWithoutUnicode() throws IOException {
-    FileInputStream i = new FileInputStream(file);
-    String output = "";
-    int data;
-    while ((data = i.read()) > 0) {
-      if (data < 0x80) {
-        output += (char) data;
+  public String content() throws IOException {
+      final FileInputStream i = new FileInputStream(this.file);
+      final StringBuilder output = new StringBuilder();
+      int data;
+      while ((data = i.read()) > 0) {
+          output.append((char) data);
       }
-    }
-    return output;
+      return output.toString();
   }
-  public void saveContent(String content) throws IOException {
-    FileOutputStream o = new FileOutputStream(file);
-    for (int i = 0; i < content.length(); i += 1) {
-      o.write(content.charAt(i));
-    }
+  public void saveContent(final String content) throws IOException {
+      final FileOutputStream o = new FileOutputStream(this.file);
+      for (int i = 0; i < content.length(); i += 1) {
+          o.write(content.charAt(i));
+      }
   }
 }
diff --git a/ParserWithoutUnicode.java b/ParserWithoutUnicode.java
new file mode 100644
index 0000000..cf3cd79
--- /dev/null
+++ b/ParserWithoutUnicode.java
@@ -0,0 +1,33 @@
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+/**
+ * This class is thread safe.
+ */
+public class ParserWithoutUnicode implements FileParser {
+  private final File file;
+  public ParserWithoutUnicode(final File file) {
+      this.file = file;
+  }
+  public synchronized File file() {
+        return file;
+    }
+  public String content() throws IOException {
+      final FileInputStream i = new FileInputStream(this.file);
+      final StringBuilder output = new StringBuilder();
+      int data;
+      while ((data = i.read()) > 0) {
+          if (data < 0x80) {
+              output.append((char) data);
+          }
+      }
+      return output.toString();
+  }
+  public void saveContent(final String content) throws IOException {
+      final FileOutputStream o = new FileOutputStream(this.file);
+      for (int i = 0; i < content.length(); i += 1) {
+          o.write(content.charAt(i));
+      }
+  }
+}