Room Rental Management System

This application was developed as a university project for the "Distributed Systems" course. The application is a room rental management system that allows users to perform manager and tenant operations. The system uses a custom implementation of the MapReduce framework for processing large volumes of data and consists of a backend implemented in Java and a mobile application in Android.

Project Requirements

Manager Functions:

• Add accommodations.
• Add available dates for rental for these accommodations.
• Display bookings for the accommodations they own.
• Manage these functions via a console application.

Tenant Functions:

• Filter accommodations based on:
  • Area of interest.
  • Desired dates.
  • Number of people.
  • Price.
  • Rating (stars).
• Book an accommodation.
• Rate the accommodation (1-5 stars).
• Perform these actions via an Android UI.
  • A search() function sends the filter to the Master asynchronously and displays the search results.
  • A book() function allows the user to book an accommodation from the search results.

System Requirements:

• The system should run distributed across multiple machines.
• Use MapReduce for processing data.
• Implement Master and Worker nodes communication using TCP sockets.
• Ensure thread synchronization using synchronized, wait, and notify.
• Data should be stored in memory (except for photos).

Backend Implementation Requirements:

• The Master must be a multi-threaded TCP Server implemented in Java.
• Workers should also be multi-threaded to handle multiple requests from the Master.
• Workers should be dynamically specified during the Master initialization.
• Implement active replication to ensure data redundancy and fault tolerance.
• Synchronize data across multiple nodes to prevent data loss if a worker node fails.

Frontend Implementation Requirements:

• Develop an Android application for the user interface.
• Communication between the Application and Master must use TCP sockets.
• Implement asynchronous communication to keep the application interactive.

Setting Up Android Studio on Windows Environment

1. Install Android Studio if necessary (version 2.1.13 or newer is recommended). If you have a version older than 2.3.0, you will need an internet connection because Android Studio will automatically download the required software.

2. Set up the environment variable ANDROID_HOME by running the command line instruction setx ANDROID_HOME C:\Users\%username%\AppData\Local\Android\sdk. If you have installed the Android SDK in another folder, enter that one instead and make sure it exists. If it's missing during step 6 execution, an error message indicating the absence of the ANDROID_HOME environment variable will appear.

3. Install the Java JDK if necessary. If it's missing during step 6 execution, an error message indicating the absence of the JAVA_HOME environment variable will appear.

4. Accept the Android SDK licenses by running the command line instruction "%ANDROID_HOME%/tools/bin/sdkmanager" --licenses and pressing y on everything. If you haven't accepted them, executing step 6 will show an error message about "accepting the Android licenses".

5. Download the application code from GitHub and place it in a folder, extracting it if necessary.

Frontend Setup

Alternatively, from the initial screen of Android Studio, select "Open an existing Android Studio project" and open the project. Once the scripts running upon opening the project from the top menu are completed, we choose "Build -> Make Project". This compiles the code and runs automatic checks but does not produce reports or signed executables.

Backend Setup

After the application is started, for starting the server run this classes in this exact order: Master, Worker1, Worker2, Worker3, Reducer, WorkerBackup

Usage

• Manager Console Application: Use the console application to add accommodations, set available dates, and view bookings.
• Tenant Android Application: Use the Android app to filter and book accommodations, as well as to rate them.

Screenshots