Single Class Proposal

.vscode/settings.json

+{
+    "java.configuration.updateBuildConfiguration": "interactive"
+}
\ No newline at end of file

messaging/src/main/java/com/crio/messaging/MessageController.java → messaging/src/main/java/com/crio/messaging/AndroidHandler.java

 package com.crio.messaging;
 
 
-public class MessageController {
+// This class contains a list of methods that will be called from
+// the Android app through a REST API server.
+// For simplicity, imagine these functions will be called directly
+// from your Android app.
+// Example: If you click send message in your Android app,
+// sendText() function will be called.
 
-    public static void send(Message message) {
+public class AndroidHandler {
+
+    public static void sendText(Message message) {
+        // 1. Discard empty strings.
+        if (message.getTextMessageContent().isEmpty()){
+            try {
+                throw new Exception("Cannot Send Empty Message!");
+            } catch (Exception e) {
+                // TODO Auto-generated catch block
+                e.printStackTrace();
+            }
+        }
+        // 3. Store the Message Safely.
+        save(message);
+        
+        // 4.Deliver the message.
+        deliverText(message);
+
+
+    }
+
+    public static void sendImage(Message message) {
         // 1. Discard empty strings.
-        if (message.getMessageContent().isEmpty()){
+        if (message.getImageMessageContent().isEmpty()){
             try {
-                throw new Exception("Cannot send empty string");
+                throw new Exception("Cannot Send Empty Image!");
             } catch (Exception e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
@@ -17,7 +43,7 @@ public class MessageController {
         save(message);
         
         // 4.Deliver the message.
-        deliver(message);
+        deliverImage(message);
 
 
     }
@@ -27,15 +53,15 @@ public class MessageController {
         System.out.println(message + " stored successfully.");
     }
 
-    private static void deliver(Message message) {
+    private static void deliverText(Message message) {
         // Logic to actually send the message to the user. It may happen through some queueing mechanism.
         // Out of syllabus for this exercise :')
 
         // # If the message is too large, don't deliver the message directly.
         // For now, drop the message, in future it can be sent as a link to a storage bucket.
-        if(message.getMessageContentSize() > 100){
+        if(message.getTextMessageContentSize() > 100){
             try {
-                throw new Exception("Message too large to send >" + message.getMessageContentSize() + " 100 bytes");
+                throw new Exception("Message too large to send >" + message.getTextMessageContentSize()+ " 100 bytes");
             } catch (Exception e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
@@ -44,5 +70,11 @@ public class MessageController {
 
         System.out.println(message + " delivered successfully.");
     }
+
+    private static void deliverImage(Message message) {
+        // Logic to actually send the message to the user. It may happen through some queueing mechanism.
+        // Out of syllabus for this exercise :')
+        System.out.println("Image"  + message + " delivered successfully.");
+    }
     
 }

messaging/src/main/java/com/crio/messaging/Main.java

 package com.crio.messaging;
 
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Base64;
+
+
 public class Main {
     public static void main(String[] args) {
-        // Call the android/iOS Controller code to send a message.
+        // Call the android/iOS Handler code to send a message.
         // In real world, these functions will be called from your REST API server methods.
         // Don't worry about them for now - let's live in a simple world :)
 
 
-        // Ankur sends a message to Abhinaya
-		Message message1 = new Message("SENDER_Ankur","RECEIVER_Abhinaya","Hello, Have you checked out https://blog.crio.do?");
-        MessageController.send(message1);
+        // Ankur sends a text message to Abhinaya
+		Message message1 = new Message();
+        message1.setSenderId("SENDER_Ankur");
+        message1.setReceiverId("RECEIVER_Abhinaya");
+        message1.setTextMessageContent("Hello, Have you checked out https://blog.crio.do?");
+        AndroidHandler.sendText(message1);
 
         // Aman sends a message to Abhiskek
-        Message message2 = new Message("SENDER_Aman","RECEIVER_Abhiskek","Hello, Hello, Enjoying Learn By Doing");
-        MessageController.send(message2);
+        Message message2 = new Message();
+        message2.setSenderId("SENDER_Aman");
+        message2.setReceiverId("RECEIVER_Abhiskek");
+        
+        String imagePath = getFilePathFromResource("CrioLogo.png");
+        message2.setImageMessageContent(imageToBase64StringConversion(imagePath), "1080x1920","Some Random Image MetaData");
+        AndroidHandler.sendImage(message2);
 	}
+
+    public static String imageToBase64StringConversion(String filePath) {
+        byte[] fileContent;
+        try {
+            fileContent = Files.readAllBytes(Paths.get(filePath));
+            return Base64.getEncoder().encodeToString(fileContent);
+        } catch (IOException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+    private static String getFilePathFromResource(String fileName){
+       return Main.class.getClassLoader().getResource(fileName).getPath();
+    }
 }

messaging/src/main/java/com/crio/messaging/Message.java

@@ -2,44 +2,90 @@ package com.crio.messaging;
 
 // Message class contains all message related variables/functions.
 public class Message {
+    //Common fields
     private String messageId;
     private String senderId;
     private String receiverId;
-    private String messageContent;
+    private MessageType messageType;
 
     // Some Common fields, can be extended to many more.
     private MessageStatus messageStatus;
 
-    public Message(String senderId, String receiverId, String messageContent) {
-        this.senderId = senderId;
-        this.receiverId = receiverId;
-        this.messageContent = messageContent;
+    //Fields related to text message.
+    private String textMessageContent;
+
+    //Fields related to image message.
+    private String imageMessageContent;
+    private String imageResolution;
+    private String imageMetaData;
+
+    //Fields relate to voice message.
+    private String voiceMessageContent;
+    private Integer durationInSec;
+    private Integer voiceQualityInKbps;
+
+    public Message(){
         this.messageStatus = MessageStatus.SENT;
     }
 
     public String getSenderId() {
         return senderId;
     }
-
+    public void setSenderId(String senderId) {
+        this.senderId = senderId;
+    }
     public String getReceiverId() {
         return receiverId;
     }
-
-    public String getMessageContent() {
-        return messageContent;
+    public void setReceiverId(String receiverId) {
+        this.receiverId = receiverId;
+    }
+    public MessageStatus getMessageStatus() {
+        return messageStatus;
+    }
+    public void setMessageStatus(MessageStatus messageStatus) {
+        this.messageStatus = messageStatus;
+    }
+    public String getTextMessageContent() {
+        return textMessageContent;
+    }
+    public void setTextMessageContent(String textMessageContent) {
+        this.messageType = MessageType.TEXT;
+        this.textMessageContent = textMessageContent;
+    }
+    public String getImageMessageContent() {
+        return imageMessageContent;
+    }
+    public void setImageMessageContent(String imageMessageContent, String imageResolution,  String imageMetaData) {
+        this.messageType =  MessageType.IMAGE;
+        this.imageMessageContent = imageMessageContent;
+        this.imageResolution = imageResolution;
+        this.imageMetaData = imageMetaData;
+    }
+    public String getVoiceMessageContent() {
+        return voiceMessageContent;
+    }
+    public void setVoiceMessageContent(String voiceMessageContent, Integer durationInSec, Integer voiceQualityInKbps) {
+        this.messageType =  MessageType.VOICE;
+        this.voiceMessageContent = voiceMessageContent;
+        this.durationInSec = durationInSec;
+        this.voiceQualityInKbps = voiceQualityInKbps;
     }
 
-    public int getMessageContentSize(){
-        return messageContent.length();
+    public int getTextMessageContentSize(){
+        return textMessageContent.length();
     }
 
 
     @Override
     public String toString() {
-        return "Message [messageContent=" + messageContent + ", messageId=" + messageId + ", messageStatus="
-                + messageStatus + ", receiverId=" + receiverId + ", senderId=" + senderId + "]";
+        return "Message [messageType=" + messageType + ", durationInSec=" + durationInSec + ", imageMessageContent=" + imageMessageContent
+                + ", imageMetaData=" + imageMetaData + ", imageResolution=" + imageResolution + ", messageStatus="
+                + messageStatus + ", receiverId=" + receiverId + ", senderId="
+                + senderId + ", textMessageContent=" + textMessageContent + ", voiceMessageContent="
+                + voiceMessageContent + ", voiceQualityInKbps=" + voiceQualityInKbps + "]";
     }
 
-
+    
 
 }

messaging/src/main/java/com/crio/messaging/MessageType.java

+package com.crio.messaging;
+
+public enum MessageType {
+    TEXT,
+    IMAGE,
+    VOICE
+}