Refactor

FileTextSource.java

@@ -0,0 +1,39 @@
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+/**
+ * This class is thread safe.
+ */
+public final class FileTextSource implements TextSource {
+  private final File file;
+
+  public FileTextSource(final File source) {
+    this.file = source;
+  }
+
+  public FileTextSource(final String path) {
+    this(new File(path));
+  }
+
+  public String getContent() throws IOException {
+    final FileInputStream i = new FileInputStream(file);
+    String output = "";
+    int data;
+    while ((data = i.read()) > 0) {
+      output += (char) data;
+    }
+    return output;
+  }
+
+  @Deprecated
+  public synchronized void setFile(File f) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Deprecated
+  public synchronized File getFile() {
+    throw new UnsupportedOperationException();
+  }
+}

FileTextStorage.java

@@ -0,0 +1,30 @@
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+public class FileTextStorage implements Storage {
+    private final TextSource source;
+    private final File destination;
+
+    public FileTextStorage(final File destination, final TextSource source) {
+        this.destination = destination;
+        this.source = source;
+    }
+
+    public FileTextStorage(final File destination, final String content) {
+        this(destination, () -> content);
+    }
+
+    @Override
+    public void save() throws IOException {
+        final FileOutputStream o = new FileOutputStream(destination);
+        final String content = this.source.getContent();
+        try {
+            for (int i = 0; i < content.length(); i += 1) {
+                o.write(content.charAt(i));
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}

Program.java

@@ -0,0 +1,45 @@
+import java.io.File;
+import java.io.IOException;
+import java.util.Scanner;
+
+public class Program implements Runnable {
+    private final TextSource source;
+    private final Storage storage;
+
+    public Program(final TextSource source, final Storage storage) {
+        this.source = source;
+        this.storage = storage;
+    }
+
+    @Override
+    public void run() {
+        try {
+            this.storage.save();
+            final String result = source.getContent();
+            System.out.println(result);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public static void main(String[] args) {
+        final File destination = new File("test.txt");
+        new Program(
+                new UnicodeFreeTextSource(
+                        new FileTextSource(
+                                destination
+                        )
+                ),
+                new FileTextStorage(
+                        destination,
+                        new UnicodeFreeTextSource(
+                                new ScannerTextSource(
+                                        new Scanner(
+                                                System.in
+                                        )
+                                )
+                        )
+                )
+        ).run();
+    }
+}

ScannerTextSource.java

@@ -0,0 +1,15 @@
+import java.io.IOException;
+import java.util.Scanner;
+
+public class ScannerTextSource implements TextSource {
+    private final Scanner source;
+
+    public ScannerTextSource(final Scanner source) {
+        this.source = source;
+    }
+
+    @Override
+    public String getContent() throws IOException {
+        return this.source.nextLine();
+    }
+}

Storage.java

@@ -0,0 +1,6 @@
+import java.io.IOException;
+
+public interface Storage {
+
+    void save() throws IOException;
+}

TextSource.java

@@ -0,0 +1,6 @@
+import java.io.IOException;
+
+public interface TextSource {
+
+    String getContent() throws IOException;
+}

UnicodeFreeTextSource.java

@@ -0,0 +1,22 @@
+import java.io.IOException;
+
+public final class UnicodeFreeTextSource implements TextSource {
+    private final TextSource origin;
+
+    public UnicodeFreeTextSource(final TextSource origin) {
+        this.origin = origin;
+    }
+
+    @Override
+    public String getContent() throws IOException {
+        final String source = origin.getContent();
+        String result = "";
+        for (final char character : source.toCharArray()) {
+            if (character > 0x80) {
+                continue;
+            }
+            result += character;
+        }
+        return result;
+    }
+}