diff --git a/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/Application.java b/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/Application.java
index 282c7e6..57c6f0f 100644
--- a/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/Application.java
+++ b/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/Application.java
@@ -13,4 +13,7 @@ public IStreamProcessorsFactory getStreamProcessorsFactory() {
     return processorsFactory;
   }
 
+  IStreamDecoratorController getStreamDecoratorController() {
+    return null;
+  }
 }
diff --git a/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/IStreamDecoratorController.java b/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/IStreamDecoratorController.java
new file mode 100644
index 0000000..ecc1ca3
--- /dev/null
+++ b/StPatrickApp-build/StPatrickApp-code/src/main/java/ch/heigvd/res/stpatrick/IStreamDecoratorController.java
@@ -0,0 +1,33 @@
+package ch.heigvd.res.stpatrick;
+
+import java.io.Reader;
+import java.io.Writer;
+
+/**
+ * A class that implements this interface has the responsibility to "decorate" a
+ * reader and a writer (to add some sort of functionality to them).
+ *
+ * @author Olivier Liechti
+ */
+public interface IStreamDecoratorController {
+
+  /**
+   * The client calls this method to ask the class to decorate an existing
+   * reader. In other words, the client tells "I have this reader, please add
+   * some functionality to it".
+   *
+   * @param inputReader the existing reader
+   * @return the decorated reader
+   */
+  Reader decorateReader(Reader inputReader);
+
+  /**
+   * The client calls this method to ask the class to decorate an existing
+   * writer. In other words, the client tells "I have this writer, please add
+   * some functionality to it".
+   *
+   * @param outputWriter the existing writer
+   * @return the decorated writer
+   */
+  Writer decorateWriter(Writer outputWriter);
+}
diff --git a/StPatrickApp-build/StPatrickApp-tests/src/test/java/ch/heigvd/res/stpatrick/ApplicationNewTest.java b/StPatrickApp-build/StPatrickApp-tests/src/test/java/ch/heigvd/res/stpatrick/ApplicationNewTest.java
new file mode 100644
index 0000000..6884c27
--- /dev/null
+++ b/StPatrickApp-build/StPatrickApp-tests/src/test/java/ch/heigvd/res/stpatrick/ApplicationNewTest.java
@@ -0,0 +1,39 @@
+package ch.heigvd.res.stpatrick;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringReader;
+import java.io.StringWriter;
+import java.io.Writer;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+/**
+ *
+ * @author Olivier Liechti
+ */
+public class ApplicationNewTest {
+
+  String input = "We are going to have an unbelievable, perhaps record-setting turnout for the inauguration, and there will be plenty of movie and entertainment stars. All the dress shops are sold out in Washington. It’s hard to find a great dress for this inauguration.";
+
+  @Test
+  public void itShouldBePossibleToGetRemoveCharacterAFromAStream() throws IOException {
+    Application application = new Application();
+    IStreamProcessorsFactory factory = application.getStreamProcessorsFactory();
+    IStreamProcessor processor = factory.getProcessor();
+    StringReader inputReader = new StringReader(input);
+    StringWriter outputWriter = new StringWriter();
+    IStreamDecoratorController controller = application.getStreamDecoratorController();
+    Reader decoratedReader = controller.decorateReader(inputReader);
+    Writer decoratedWriter = controller.decorateWriter(outputWriter);
+    try {
+      processor.process(decoratedReader, decoratedWriter);
+      String output = outputWriter.toString();
+      assertEquals(-1, output.indexOf('a'));
+      assertEquals(-1, output.indexOf('A'));
+    } catch (IOException e) {
+      throw e;
+    }
+  }
+
+}