Merge pull request #70 from HarryDulaney/new-solutions

bug fix ex 31 02

README.md

@@ -2,9 +2,9 @@
 
 <img style="width:25%; height:25%;" src="./resources/coverpicture.png" alt="header-img-book-cover">
 
-### This repo contains my solutions to the end-of-chapter exercise’s from <a href="https://www.amazon.com/Intro-Java-Programming-Comprehensive-Version/dp/0133761312">Y. Daniel Liang’s Intro to Java Programming (10th Edition)</a>
+### This repo contains <a href="#exercise-solutions-shortcut">my solutions to the end-of-chapter exercise’s</a> from <a href="https://www.amazon.com/Intro-Java-Programming-Comprehensive-Version/dp/0133761312">Y. Daniel Liang’s Intro to Java Programming (10th Edition)</a>
 
-### I've included links below to all the freely accessible compainion material and quick links to navigate through my solutions by chapter.
+### I've included links below to all the freely accessible companion material and quick links to navigate through my solutions by chapter.
 
 ### If you would like to contribute, please see: <a href="#contribute">Ways to Contribute</a>
 
@@ -63,7 +63,7 @@ ____
 
 ____
 
-<h1>Exercise Solutions:</h1>
+<h1 id="exercise-solutions-shortcut">Exercise Solutions:</h1>
 <h5>Quick Links to navigate these solutions by chapter</h5>
 <h6>
 <img src="./resources/images/icons8-complete-26.png" alt="complete-check-img"/>

ch_31/exercise31_02/BmiDto.java

@@ -0,0 +1,28 @@
+package ch_31.exercise31_02;
+
+/**
+ * Data Transfer Object for BMI data
+ * <p>
+ * This class is used to transfer data from the client to the server.
+ * For Exercise31_02, the client sends the weight and height for a person to the server.
+ */
+public class BmiDto {
+    private double weight;
+    private double height;
+
+    public BmiDto() {
+    }
+
+    public BmiDto(double weight, double height) {
+        this.weight = weight;
+        this.height = height;
+    }
+
+    public double getWeight() {
+        return weight;
+    }
+
+    public double getHeight() {
+        return height;
+    }
+}

ch_31/exercise31_02/Exercise31_02.java

@@ -0,0 +1,21 @@
+package ch_31.exercise31_02;
+
+import javafx.application.Application;
+import javafx.application.Platform;
+import javafx.stage.Stage;
+
+/**
+ * *31.2 (BMI server) Write a server for a client. The client sends the weight and
+ * height for a person to the server (see Figure  31.18a). The server computes
+ * BMI (Body Mass Index) and sends back to the client a string that reports the
+ * BMI (see Figure 31.18b). See Section 3.8 for computing BMI. Name the client
+ * Exercise31_02Client and the server Exercise31_02Server.
+ */
+public class Exercise31_02 extends Application {
+    @Override
+    public void start(Stage primaryStage) throws Exception {
+        System.out.println("##-_-_--_--_--__-_-- Starting: Exercise31_02 --_-__--__--__--_--_--##");
+        Platform.runLater(() -> new Exercise31_02Server().start(new Stage()));
+        Platform.runLater(() -> new Exercise31_02Client().start(new Stage()));
+    }
+}

ch_31/exercise31_02/Exercise31_02Client.java

@@ -0,0 +1,106 @@
+package ch_31.exercise31_02;
+
+import javafx.application.Application;
+import javafx.event.ActionEvent;
+import javafx.event.EventHandler;
+import javafx.geometry.HPos;
+import javafx.geometry.Pos;
+import javafx.geometry.VPos;
+import javafx.scene.Scene;
+import javafx.scene.control.Button;
+import javafx.scene.control.Label;
+import javafx.scene.control.TextArea;
+import javafx.scene.control.TextField;
+import javafx.scene.layout.GridPane;
+import javafx.stage.Stage;
+
+import java.io.*;
+import java.net.Socket;
+
+public class Exercise31_02Client extends Application {
+    private TextField weightTextInput = new TextField();
+    private TextField heightTextInput = new TextField();
+    private TextArea displayResultTextArea = new TextArea();
+
+    private Button submitButton = new Button("Submit");
+
+    // Host name or ip
+    String host = "localhost";
+
+    private ObjectOutputStream toServer;
+    private DataInputStream fromServer;
+
+    public Exercise31_02Client() {
+        System.out.println("##-_-_--_--_--__-_-- Starting: Exercise31_02Client --_-__--__--__--_--_--##");
+    }
+
+    @Override
+    public void start(Stage primaryStage) {
+        Stage stage = new Stage();
+        GridPane pane = new GridPane();
+        pane.add(new Label("Weight in pounds"), 0, 0);
+        pane.add(weightTextInput, 1, 0);
+        pane.add(new Label("Height in inches"), 0, 1);
+        pane.add(heightTextInput, 1, 1);
+        pane.add(submitButton, 1, 3);
+        pane.add(displayResultTextArea, 1, 4);
+        GridPane.setHalignment(submitButton, HPos.RIGHT);
+        GridPane.setValignment(displayResultTextArea, VPos.BOTTOM);
+        pane.setAlignment(Pos.CENTER);
+        weightTextInput.setPrefColumnCount(15);
+        heightTextInput.setPrefColumnCount(15);
+        submitButton.setOnAction(new ButtonListener());
+
+        Scene scene = new Scene(pane, 450, 200);
+        stage.setTitle("BMI Client");
+        stage.setScene(scene);
+        stage.show();
+
+        try (Socket socket = new Socket(host, 8000)) {
+            // Create an output stream to the server
+            toServer = new ObjectOutputStream(socket.getOutputStream());
+            // Create an input stream from the server
+            fromServer = new DataInputStream(socket.getInputStream());
+        } catch (IOException ex) {
+            System.out.println("##----------- Client Error: IOException: " + ex.getMessage() + " -----------##");
+        }
+    }
+
+    /**
+     * Custom event handler for the submit button
+     */
+    private class ButtonListener implements EventHandler<ActionEvent> {
+        @Override
+        public void handle(ActionEvent e) {
+            try {
+                // Get weight and height from the text fields
+                double weight = Double.parseDouble(weightTextInput.getText().trim());
+                double height = Double.parseDouble(heightTextInput.getText().trim());
+                // Create a BmiDto and send to the server
+                BmiDto s = new BmiDto(weight, height);
+                toServer.writeObject(s);
+                toServer.flush();
+                // Get resulting BMI from the server
+                double bmi = fromServer.readDouble();
+                // Display to the text area
+                displayResultTextArea.setText("Weight: " + weight + "\nHeight: " + height + "\nBMI is: " + bmi
+                        + "\n" + getCategory(bmi));
+            } catch (IOException ex) {
+                System.out.println("##----------- Client Error: IOException: " + ex.getMessage() + " -----------##");
+            }
+        }
+    }
+
+    private String getCategory(double bmi) {
+        if (bmi < 18.5) {
+            return "Underweight";
+        } else if (bmi < 25) {
+            return "Normal";
+        } else if (bmi < 30) {
+            return "Overweight";
+        } else {
+            return "Obese";
+        }
+    }
+
+}

ch_31/exercise31_02/Exercise31_02Server.java

@@ -0,0 +1,84 @@
+package ch_31.exercise31_02;
+
+import javafx.application.Application;
+import javafx.application.Platform;
+import javafx.scene.Scene;
+import javafx.scene.control.ScrollPane;
+import javafx.scene.control.TextArea;
+import javafx.stage.Stage;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.Date;
+import java.util.Objects;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+public class Exercise31_02Server extends Application {
+    private static final double KILOGRAMS_PER_POUND = 0.45359237;
+    private static final double METERS_PER_INCH = 0.0254;
+
+    private AtomicBoolean isRunning = new AtomicBoolean(true);
+
+    public Exercise31_02Server() {
+        System.out.println("##-_-_--_--_--__-_-- Starting: Exercise31_02Server --_-__--__--__--_--_--##");
+    }
+
+
+    @Override
+    public void start(Stage primaryStage) {
+        TextArea displayLogTextArea = new TextArea();
+        Scene scene = new Scene(new ScrollPane(displayLogTextArea), 450, 200);
+        primaryStage.setTitle("TicTacToeServer");
+        primaryStage.setScene(scene);
+        primaryStage.show();
+        new Thread(() -> runServer(displayLogTextArea)).start();
+    }
+
+    private void runServer(TextArea displayLogTextArea) {
+        /* Create a server socket. Use try with resources to close the socket automatically */
+        try (ServerSocket serverSocket = new ServerSocket(8000)) {
+            // Listen for a connection request
+            Socket socket = socket = serverSocket.accept();
+            // Create data input and output streams
+            try (ObjectInputStream inputFromClient = new ObjectInputStream(
+                    socket.getInputStream())) {
+                try (DataOutputStream outputToClient = new DataOutputStream(
+                        socket.getOutputStream())) {
+
+                    Platform.runLater(() -> displayLogTextArea.appendText(new Date() +
+                            ": Server started at socket 8000\n"));
+                    while (true) {
+                        if (!isRunning.get()) {
+                            break;
+                        }
+                        if (inputFromClient.available() > 0) {
+                            // Receive Object from the client
+                            Object object = inputFromClient.readObject();
+                            if (Objects.nonNull(object) && object instanceof BmiDto) {
+                                BmiDto bmiDto = (BmiDto) object;
+                                double weight = bmiDto.getWeight();
+                                double height = bmiDto.getHeight();
+                                double bmi = calculateBmi(weight, height);
+                                // Send area back to the client
+                                outputToClient.writeDouble(bmi);
+                            }
+                        }
+
+                    }
+                }
+            }
+
+        } catch (ClassNotFoundException | IOException ex) {
+            System.out.println("##----------- Server Error: Exception: " + ex.getMessage() + " -----------##");
+        }
+    }
+
+    private double calculateBmi(double weight, double height) {
+        double weightInKilograms = weight * KILOGRAMS_PER_POUND;
+        double heightInMeters = height * METERS_PER_INCH;
+        return weightInKilograms /
+                (heightInMeters * heightInMeters);
+    }
+
+}