Train Tracking System

A Java-based Train Tracking System that fetches real-time train details and displays them in a user-friendly format.

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Features

• Accepts train numbers as input.
• Fetches train status and station details from an API.
• Displays the details in a tabular format.
• Handles errors gracefully (e.g., invalid train numbers, connectivity issues).

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Code Structure

Interface: Trackable

• Purpose: Defines common methods for trackable entities like trains.
• Methods:
  • getId(): Returns the ID of the entity.
  • getName(): Returns the name of the entity.
  • getStatus(): Fetches the current status of the entity.

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Base Class: TrainBase

• Purpose: Provides shared properties (id and name) for trackable entities.
• Key Methods:
  • getId(): Getter for id.
  • getName(): Getter for name.

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Train Class

• Extends: TrainBase
• Implements: Trackable
• Purpose: Represents a specific train.
• Key Methods:
  • getStatus(): Calls the TrainTracker.getTrainStatus() method to fetch the train's live status.

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TrainTracker Class

• Purpose: Handles all logic related to fetching and processing train status data.
• Key Functions:
  1. getTrainStatus(String trainNo):
     • Connects to the API using the train number.
     • Sends an HTTP GET request.
     • Processes the response to extract meaningful data.
  2. parseJSON(String json):
     • Parses the JSON response into a structured Map.
     • Extracts specific keys like train_name, message, updated_time, and station details.
  3. extractValue(String json, String key):
     • Retrieves the value of a specific key from the JSON string.
  4. extractArray(String json, String key):
     • Extracts the array (e.g., station details) corresponding to a key.
  5. parseArray(String array):
     • Converts the station data into a list of maps for easier processing.

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Main Class (samp)

• Purpose: Entry point of the program.
• Key Functionality:
  1. Displays a welcome message.
  2. Prompts the user to enter a train number.
  3. Creates a Train object and fetches its status.
  4. Formats and displays the train details and station list in a user-friendly tabular format.

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Sample Output

Input:

Enter Train Number to Track: 22667

Output:

Welcome to Train Tracking System
Enter Train Number to Track: 22667

Tracking Train: 22667 Ncj Cbe Sf Exp Running Status
Crossed Erode Jn at 21:17
Last Updated: Updated few seconds ago

Station Details:
Station Name          Distance   Timing      Delay      Platform   Halt
---------------------------------------------------------------------------
Coimbatore Jn         -          19:32/19:30 2min       4          Source
Tiruppur              51 km      20:15/20:10 5min       2          2min
Erode Jn              101 km     21:17/20:55 22min      1          25min
...

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Error Handling

1. Invalid Train Number:

   • If the API returns success: false, the program displays an error message.

2. Connectivity Issues:

   • Catches exceptions during the HTTP request and prints the stack trace.

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Setup and Usage

Prerequisites

• Java Development Kit (JDK) installed on your system.
• Internet connection for API access.

Steps to Run

1. Clone this repository:

   git clone <repository-url>
   cd <repository-folder>

2. Compile the program:

   javac samp.java

3. Run the program:

   java samp

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Possible Enhancements

• Input Validation:
  • Add validation for train numbers.
• Error Logging:
  • Log errors to a file instead of printing stack traces.
• UI:
  • Develop a graphical user interface for better usability.

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License

This project is open-source and available under the MIT License.