Refactoring for Parser

Parser.java

@@ -2,45 +2,68 @@
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
 /**
+ * IO operations with file.
  * This class is thread safe.
- */
+ * TODO: Rename the 'Parser' name to 'SyncFileOperations'
+ * */
 public class Parser {
-  private File file;
-  public synchronized void setFile(File f) {
-    file = f;
-  }
-  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;
+    private final File file;
+    private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock(true);
+
+    public Parser(File file) {
+        this.file = 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;
-      }
+
+    /**
+     * Read file content
+     */
+    public String getContent() throws IOException {
+        readWriteLock.readLock().lock();
+        try (FileInputStream inputStream = new FileInputStream(file)) {
+            StringBuilder output = new StringBuilder();
+            int data;
+            while ((data = inputStream.read()) > 0) {
+                output.append((char) data);
+            }
+            inputStream.close();
+            return output.toString();
+        } finally {
+            readWriteLock.readLock().unlock();
+        }
     }
-    return output;
-  }
-  public void saveContent(String content) {
-    FileOutputStream o = new FileOutputStream(file);
-    try {
-      for (int i = 0; i < content.length(); i += 1) {
-        o.write(content.charAt(i));
-      }
-    } catch (IOException e) {
-      e.printStackTrace();
+
+    /**
+     * Save content to file
+     * */
+    public void saveContent(String content) {
+        readWriteLock.writeLock().lock();
+        try {
+            try (FileOutputStream outputStream = new FileOutputStream(file)) {
+                outputStream.write(content.getBytes(StandardCharsets.UTF_8));
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        } finally {
+            readWriteLock.writeLock().unlock();
+        }
+    }
+
+    /**
+     * TODO: Data should be cleaned outside the class.
+     **/
+    @Deprecated
+    public String getContentWithoutUnicode() throws IOException {
+        StringBuilder output = new StringBuilder();
+        for (char ch : getContent().toCharArray()) {
+            if (ch < 0x80) {
+                output.append(ch);
+            }
+        }
+        return output.toString();
     }
-  }
 }