Add base files

src/main/java/com/university/chat/Common/ChatMessage.java

@@ -0,0 +1,25 @@
+package com.university.chat.Common;
+
+import java.io.Serializable;
+
+public class ChatMessage implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    private MessageType type;
+    private String sender;
+    private String receiver;
+    private String content;
+
+    public ChatMessage(MessageType type, String sender, String receiver, String content) {
+        this.type = type;
+        this.sender = sender;
+        this.receiver = receiver;
+        this.content = content;
+    }
+
+    public MessageType getType() { return type; }
+    public String getSender() { return sender; }
+    public String getReceiver() { return receiver; }
+    public String getContent() { return content; }
+}