📈 Stocks Processing Application

Welcome to the Stocks Processing Application! This Java-based application processes stock market data based on various criteria such as sectors, market capitalization, and price-to-earnings ratios. The program generates useful output files containing filtered stock data, making it easier to analyze market trends.

🚀 Features

• Process Stock Data: Reads stock data from a file and processes it based on the user's input.
• Filter by Sector: Easily filter stocks by industry sectors such as Technology, Healthcare, Financials, and more.
• Price-to-Earnings Ratio Analysis: Generate lists of stocks based on whether their P/E ratio is above or below a given value.
• Market Capitalization Sorting: Sort companies by market capitalization (in billions or trillions) in ascending order.
• Company Name Sorting: Sort companies alphabetically by their name.
• Custom Exception Handling: Handles invalid user inputs with a custom exception called InvalidInputException.

📝 Input File Structure

The application processes an input file (stockData.txt) where each line follows this format:

Ticker,Company Name,Sector,Market Capitalization,Current Price,P/E Ratio

Example Data:

AAPL,Apple Inc.,Technology,2.5T,145.32,25.38
MSFT,Microsoft Corporation,Technology,2.2T,280.74,31.15
JPM,JPMorgan Chase & Co.,Financials,463B,154.78,12.58

The data is separated by commas without spaces, and the market capitalization values end with either 'B' for billions or 'T' for trillions.

🛠️ Methods Overview

The application implements the following methods:

1. makeSectorFile(String sector)

• Creates a file called sectors.txt containing stock tickers and current prices for companies in the specified sector.
• Output Format:

  [Stock Ticker] | [Current Price]
  

2. makePriceToEarningsFile(double priceToEarnings, boolean greaterThan)

• Creates a file called priceToEarnings.txt containing stocks filtered by P/E ratios.
• If greaterThan is true, it includes stocks with a P/E ratio greater than or equal to the given value. If false, it includes those with a lower P/E ratio.

3. makeSortedMarketCapFile()

• Creates a file called sortedMarketCap.txt that contains all stocks sorted by market capitalization in ascending order.

4. makeSortedCompanyNameFile()

• Creates a file called sortedCompanyName.txt with all stock data sorted alphabetically by company name.

5. validateInput(String sector, String marketCapitalization, double currentPrice, double priceToEarnings)

• Ensures that user input is valid. If invalid, throws a custom InvalidInputException with a specific error message.

🚧 Custom Exception Handling

The custom exception class InvalidInputException is thrown when the user provides invalid input. The conditions for valid input are as follows:

• Sector: Must be one of the following:
  {Technology, Consumer Discretionary, Communication Services, Financials, Healthcare, Consumer Staples, Energy, Industrials, Utilities}
• Market Capitalization: Must end in either 'B' (Billions) or 'T' (Trillions).
• Current Price: Must be between 0.01 and 10,000 inclusive.
• Price-to-Earnings Ratio: Must be between 1 and 100 inclusive.

If any of these conditions are not met, an exception is thrown with a relevant error message, such as:

• "Invalid Sector: Sector must be one of the following...".
• "Market Capitalization must end in either B for Billion or T for Trillion".
• "Current Price must be between 0.01 and 10000 inclusive".
• "Price to Earnings must be between 1 and 100 inclusive".

🔧 Sorting Algorithms

For both the Market Capitalization and Company Name sorting, the program implements custom sorting using nested loops. No built-in sorting methods (e.g., Collections.sort()) are used, and the sorting is done manually to reinforce basic algorithmic concepts.

Sorting by Market Capitalization:

• Convert the values from trillions and billions to a comparable numeric format.
• Sort them in ascending order.

Sorting by Company Name:

• Use the String.compareTo() method to sort company names alphabetically.

💾 Output Example

For a sector file generated using the "Energy" sector, the output in sectors.txt might look like this:

XOM | 57.32
CVX | 106.34

📂 File Structure

/project-root
  ├── /src
  │   ├── Stocks.java
  │   ├── InvalidInputException.java
  │   └── stockData.txt
  ├── README.md
  └── /output
      ├── sectors.txt
      ├── priceToEarnings.txt
      ├── sortedMarketCap.txt
      └── sortedCompanyName.txt

🖥️ How to Run

1. Compile the Java program:

   javac Stocks.java
   

2. Run the program:

   java Stocks
   

3. Follow the prompts to enter input for sector, price-to-earnings ratio, and sorting preferences.