feature: Add Service to Worker Pattern (#2004)

* update service to worker

* update pom.xml and make GiantModel public

* add javadoc for GaintModel

service-to-worker/src/main/java/com/iluwatar/servicetoworker/Action.java

@@ -0,0 +1,61 @@
+package com.iluwatar.servicetoworker;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+
+/**
+ * The type Action (Worker), which can process user input and perform a specific update on the
+ * model.
+ */
+public class Action {
+
+  public GiantModel giant;
+
+  /**
+   * Instantiates a new Action.
+   *
+   * @param giant the giant
+   */
+  public Action(GiantModel giant) {
+    this.giant = giant;
+  }
+
+  /**
+   * Update model based on command.
+   *
+   * @param command the command
+   */
+  public void updateModel(Command command) {
+    setFatigue(command.getFatigue());
+    setHealth(command.getHealth());
+    setNourishment(command.getNourishment());
+  }
+
+  /**
+   * Sets health.
+   *
+   * @param health the health
+   */
+  public void setHealth(Health health) {
+    giant.setHealth(health);
+  }
+
+  /**
+   * Sets fatigue.
+   *
+   * @param fatigue the fatigue
+   */
+  public void setFatigue(Fatigue fatigue) {
+    giant.setFatigue(fatigue);
+  }
+
+  /**
+   * Sets nourishment.
+   *
+   * @param nourishment the nourishment
+   */
+  public void setNourishment(Nourishment nourishment) {
+    giant.setNourishment(nourishment);
+  }
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/App.java

@@ -0,0 +1,47 @@
+package com.iluwatar.servicetoworker;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+
+/**
+ * The front controller intercepts all requests and performs common functions using decorators. The
+ * front controller passes request information to the dispatcher, which uses the request and an
+ * internal model to chooses and execute appropriate actions. The actions process user input,
+ * translating it into appropriate updates to the model. The model applies business rules and stores
+ * the data persistently. Based on the user input and results of the actions, the dispatcher chooses
+ * a view. The view transforms the updated model data into a form suitable for the user.
+ */
+public class App {
+
+  /**
+   * Program entry point.
+   *
+   * @param args command line args
+   */
+  public static void main(String[] args) {
+    // create model, view and controller
+    var giant1 = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT, Nourishment.SATURATED);
+    var giant2 = new GiantModel("giant2", Health.DEAD, Fatigue.SLEEPING, Nourishment.STARVING);
+    var action1 = new Action(giant1);
+    var action2 = new Action(giant2);
+    var view = new GiantView();
+    var dispatcher = new Dispatcher(view);
+    dispatcher.addAction(action1);
+    dispatcher.addAction(action2);
+    var controller = new GiantController(dispatcher);
+
+    // initial display
+    controller.updateView(giant1);
+    controller.updateView(giant2);
+
+    // controller receives some interactions that affect the giant
+    controller.setCommand(new Command(Fatigue.SLEEPING, Health.HEALTHY, Nourishment.STARVING), 0);
+    controller.setCommand(new Command(Fatigue.ALERT, Health.HEALTHY, Nourishment.HUNGRY), 1);
+
+    // redisplay
+    controller.updateView(giant1);
+    controller.updateView(giant2);
+    // controller receives some interactions that affect the giant
+  }
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/Command.java

@@ -0,0 +1,32 @@
+package com.iluwatar.servicetoworker;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import lombok.Getter;
+
+/**
+ * The type Command.
+ */
+public class Command {
+
+  @Getter
+  private final Fatigue fatigue;
+  @Getter
+  private final Health health;
+  @Getter
+  private final Nourishment nourishment;
+
+  /**
+   * Instantiates a new Command.
+   *
+   * @param fatigue     the fatigue
+   * @param health      the health
+   * @param nourishment the nourishment
+   */
+  public Command(Fatigue fatigue, Health health, Nourishment nourishment) {
+    this.fatigue = fatigue;
+    this.health = health;
+    this.nourishment = nourishment;
+  }
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/Dispatcher.java

@@ -0,0 +1,55 @@
+package com.iluwatar.servicetoworker;
+
+import java.util.ArrayList;
+import java.util.List;
+import lombok.Getter;
+
+/**
+ * The type Dispatcher, which encapsulates worker and view selection based on request information
+ * and/or an internal navigation model.
+ */
+public class Dispatcher {
+
+  @Getter
+  private final GiantView giantView;
+  private final List<Action> actions;
+
+  /**
+   * Instantiates a new Dispatcher.
+   *
+   * @param giantView the giant view
+   */
+  public Dispatcher(GiantView giantView) {
+    this.giantView = giantView;
+    this.actions = new ArrayList<>();
+  }
+
+  /**
+   * Add an action.
+   *
+   * @param action the action
+   */
+  void addAction(Action action) {
+    actions.add(action);
+  }
+
+  /**
+   * Perform an action.
+   *
+   * @param s           the s
+   * @param actionIndex the action index
+   */
+  public void performAction(Command s, int actionIndex) {
+    actions.get(actionIndex).updateModel(s);
+  }
+
+  /**
+   * Update view.
+   *
+   * @param giantModel the giant model
+   */
+  public void updateView(GiantModel giantModel) {
+    giantView.displayGiant(giantModel);
+  }
+
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/GiantController.java

@@ -0,0 +1,41 @@
+package com.iluwatar.servicetoworker;
+
+import lombok.Getter;
+
+/**
+ * GiantController can update the giant data and redraw it using the view. Singleton object that
+ * intercepts all requests and performs common functions.
+ */
+public class GiantController {
+
+  public Dispatcher dispatcher;
+
+  /**
+   * Instantiates a new Giant controller.
+   *
+   * @param dispatcher the dispatcher
+   */
+  public GiantController(Dispatcher dispatcher) {
+    this.dispatcher = dispatcher;
+  }
+
+  /**
+   * Sets command to control the dispatcher.
+   *
+   * @param s     the s
+   * @param index the index
+   */
+  public void setCommand(Command s, int index) {
+    dispatcher.performAction(s, index);
+  }
+
+  /**
+   * Update view. This is a simple implementation, in fact, View can be implemented in a concrete
+   * way
+   *
+   * @param giantModel the giant model
+   */
+  public void updateView(GiantModel giantModel) {
+    dispatcher.updateView(giantModel);
+  }
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/GiantModel.java

@@ -0,0 +1,86 @@
+package com.iluwatar.servicetoworker;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import lombok.Getter;
+
+/**
+ * GiantModel contains the giant data.
+ */
+public class GiantModel {
+
+  private final com.iluwatar.model.view.controller.GiantModel model;
+  @Getter
+  private final String name;
+
+  /**
+   * Instantiates a new Giant model.
+   *
+   * @param name        the name
+   * @param health      the health
+   * @param fatigue     the fatigue
+   * @param nourishment the nourishment
+   */
+  GiantModel(String name, Health health, Fatigue fatigue, Nourishment nourishment) {
+    this.name = name;
+    this.model = new com.iluwatar.model.view.controller.GiantModel(health, fatigue,
+        nourishment);
+  }
+
+  /**
+   * Gets health.
+   *
+   * @return the health
+   */
+  Health getHealth() {
+    return model.getHealth();
+  }
+
+  /**
+   * Sets health.
+   *
+   * @param health the health
+   */
+  void setHealth(Health health) {
+    model.setHealth(health);
+  }
+
+  /**
+   * Gets fatigue.
+   *
+   * @return the fatigue
+   */
+  Fatigue getFatigue() {
+    return model.getFatigue();
+  }
+
+  void setFatigue(Fatigue fatigue) {
+    model.setFatigue(fatigue);
+  }
+
+  /**
+   * Gets nourishment.
+   *
+   * @return the nourishment
+   */
+  Nourishment getNourishment() {
+    return model.getNourishment();
+  }
+
+  /**
+   * Sets nourishment.
+   *
+   * @param nourishment the nourishment
+   */
+  void setNourishment(Nourishment nourishment) {
+    model.setNourishment(nourishment);
+  }
+
+  @Override
+  public String toString() {
+    return String
+        .format("Giant %s, The giant looks %s, %s and %s.", name,
+            model.getHealth(), model.getFatigue(), model.getNourishment());
+  }
+}

service-to-worker/src/main/java/com/iluwatar/servicetoworker/GiantView.java

@@ -0,0 +1,19 @@
+package com.iluwatar.servicetoworker;
+
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * GiantView displays the giant.
+ */
+@Slf4j
+public class GiantView {
+
+  /**
+   * Display the GiantModel simply.
+   *
+   * @param giant the giant
+   */
+  public void displayGiant(GiantModel giant) {
+    LOGGER.info(giant.toString());
+  }
+}

service-to-worker/src/test/java/com/iluwatar/servicetoworker/ActionTest.java

@@ -0,0 +1,87 @@
+package com.iluwatar.servicetoworker;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import org.junit.jupiter.api.Test;
+
+/**
+ * The type Action test.
+ */
+class ActionTest {
+
+  /**
+   * Verify if the health value is set properly though the constructor and setter
+   */
+  @Test
+  void testSetHealth() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    assertEquals(Health.HEALTHY, model.getHealth());
+    var messageFormat = "Giant giant1, The giant looks %s, alert and saturated.";
+    for (final var health : Health.values()) {
+      action.setHealth(health);
+      assertEquals(health, model.getHealth());
+      assertEquals(String.format(messageFormat, health), model.toString());
+    }
+  }
+
+  /**
+   * Verify if the fatigue level is set properly though the constructor and setter
+   */
+  @Test
+  void testSetFatigue() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    assertEquals(Fatigue.ALERT, model.getFatigue());
+    var messageFormat = "Giant giant1, The giant looks healthy, %s and saturated.";
+    for (final var fatigue : Fatigue.values()) {
+      action.setFatigue(fatigue);
+      assertEquals(fatigue, model.getFatigue());
+      assertEquals(String.format(messageFormat, fatigue), model.toString());
+    }
+  }
+
+  /**
+   * Verify if the nourishment level is set properly though the constructor and setter
+   */
+  @Test
+  void testSetNourishment() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    assertEquals(Nourishment.SATURATED, model.getNourishment());
+    var messageFormat = "Giant giant1, The giant looks healthy, alert and %s.";
+    for (final var nourishment : Nourishment.values()) {
+      action.setNourishment(nourishment);
+      assertEquals(nourishment, model.getNourishment());
+      assertEquals(String.format(messageFormat, nourishment), model.toString());
+    }
+  }
+
+  /**
+   * Test update model.
+   */
+  @Test
+  void testUpdateModel() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    assertEquals(Nourishment.SATURATED, model.getNourishment());
+    for (final var nourishment : Nourishment.values()) {
+      for (final var fatigue : Fatigue.values()) {
+        for (final var health : Health.values()) {
+          Command cmd = new Command(fatigue, health, nourishment);
+          action.updateModel(cmd);
+          assertEquals(nourishment, model.getNourishment());
+          assertEquals(fatigue, model.getFatigue());
+          assertEquals(health, model.getHealth());
+        }
+      }
+    }
+  }
+}

service-to-worker/src/test/java/com/iluwatar/servicetoworker/AppTest.java

@@ -0,0 +1,16 @@
+package com.iluwatar.servicetoworker;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+/**
+ * Application test
+ */
+class AppTest {
+
+  @Test
+  void shouldExecuteApplicationWithoutException() {
+    assertDoesNotThrow(() -> App.main(new String[]{}));
+  }
+}

service-to-worker/src/test/java/com/iluwatar/servicetoworker/DispatcherTest.java

@@ -0,0 +1,52 @@
+package com.iluwatar.servicetoworker;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import org.junit.jupiter.api.Test;
+
+/**
+ * The type Dispatcher test.
+ */
+class DispatcherTest {
+
+  /**
+   * Test perform action.
+   */
+  @Test
+  void testPerformAction() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    GiantView giantView = new GiantView();
+    Dispatcher dispatcher = new Dispatcher(giantView);
+    assertEquals(Nourishment.SATURATED, model.getNourishment());
+    dispatcher.addAction(action);
+    for (final var nourishment : Nourishment.values()) {
+      for (final var fatigue : Fatigue.values()) {
+        for (final var health : Health.values()) {
+          Command cmd = new Command(fatigue, health, nourishment);
+          dispatcher.performAction(cmd, 0);
+          assertEquals(nourishment, model.getNourishment());
+          assertEquals(fatigue, model.getFatigue());
+          assertEquals(health, model.getHealth());
+        }
+      }
+    }
+  }
+
+  @Test
+  void testUpdateView() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    GiantView giantView = new GiantView();
+    Dispatcher dispatcher = new Dispatcher(giantView);
+    assertDoesNotThrow(() -> dispatcher.updateView(model));
+  }
+}
+
+
+

service-to-worker/src/test/java/com/iluwatar/servicetoworker/GiantControllerTest.java

@@ -0,0 +1,49 @@
+package com.iluwatar.servicetoworker;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import org.junit.jupiter.api.Test;
+
+
+/**
+ * The type Giant controller test.
+ */
+class GiantControllerTest {
+
+  /**
+   * Test set command.
+   */
+  @Test
+  void testSetCommand() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    Action action = new Action(model);
+    GiantView giantView = new GiantView();
+    Dispatcher dispatcher = new Dispatcher(giantView);
+    assertEquals(Nourishment.SATURATED, model.getNourishment());
+    dispatcher.addAction(action);
+    GiantController controller = new GiantController(dispatcher);
+    controller.setCommand(new Command(Fatigue.ALERT, Health.HEALTHY, Nourishment.HUNGRY), 0);
+    assertEquals(Fatigue.ALERT, model.getFatigue());
+    assertEquals(Health.HEALTHY, model.getHealth());
+    assertEquals(Nourishment.HUNGRY, model.getNourishment());
+  }
+
+  /**
+   * Test update view.
+   */
+  @Test
+  void testUpdateView() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    GiantView giantView = new GiantView();
+    Dispatcher dispatcher = new Dispatcher(giantView);
+    GiantController giantController = new GiantController(dispatcher);
+    assertDoesNotThrow(() -> giantController.updateView(model));
+  }
+
+}

service-to-worker/src/test/java/com/iluwatar/servicetoworker/GiantModelTest.java

@@ -0,0 +1,62 @@
+package com.iluwatar.servicetoworker;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import org.junit.jupiter.api.Test;
+
+/**
+ * The type Giant model test.
+ */
+class GiantModelTest {
+
+  /**
+   * Verify if the health value is set properly though the constructor and setter
+   */
+  @Test
+  void testSetHealth() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    assertEquals(Health.HEALTHY, model.getHealth());
+    var messageFormat = "Giant giant1, The giant looks %s, alert and saturated.";
+    for (final var health : Health.values()) {
+      model.setHealth(health);
+      assertEquals(health, model.getHealth());
+      assertEquals(String.format(messageFormat, health), model.toString());
+    }
+  }
+
+  /**
+   * Verify if the fatigue level is set properly though the constructor and setter
+   */
+  @Test
+  void testSetFatigue() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    assertEquals(Fatigue.ALERT, model.getFatigue());
+    var messageFormat = "Giant giant1, The giant looks healthy, %s and saturated.";
+    for (final var fatigue : Fatigue.values()) {
+      model.setFatigue(fatigue);
+      assertEquals(fatigue, model.getFatigue());
+      assertEquals(String.format(messageFormat, fatigue), model.toString());
+    }
+  }
+
+  /**
+   * Verify if the nourishment level is set properly though the constructor and setter
+   */
+  @Test
+  void testSetNourishment() {
+    final var model = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    assertEquals(Nourishment.SATURATED, model.getNourishment());
+    var messageFormat = "Giant giant1, The giant looks healthy, alert and %s.";
+    for (final var nourishment : Nourishment.values()) {
+      model.setNourishment(nourishment);
+      assertEquals(nourishment, model.getNourishment());
+      assertEquals(String.format(messageFormat, nourishment), model.toString());
+    }
+  }
+}

service-to-worker/src/test/java/com/iluwatar/servicetoworker/GiantViewTest.java

@@ -0,0 +1,25 @@
+package com.iluwatar.servicetoworker;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import com.iluwatar.model.view.controller.Fatigue;
+import com.iluwatar.model.view.controller.Health;
+import com.iluwatar.model.view.controller.Nourishment;
+import org.junit.jupiter.api.Test;
+
+/**
+ * The type Giant view test.
+ */
+class GiantViewTest {
+
+  /**
+   * Test dispaly giant.
+   */
+  @Test
+  void testDispalyGiant() {
+    GiantModel giantModel = new GiantModel("giant1", Health.HEALTHY, Fatigue.ALERT,
+        Nourishment.SATURATED);
+    GiantView giantView = new GiantView();
+    assertDoesNotThrow(() -> giantView.displayGiant(giantModel));
+  }
+}