A web banking application built in Java 17 using Gradle, PostgreSQL, and JDBC. This application manages banks, accounts, users, and transactions for Clever-Bank. It implements various banking operations such as accruing interest, withdraws, transfers and refills.

1. Project Overview
2. Requirements
3. Usage
4. Features
5. File Structure
6. Configuration
7. Running the Application
8. Running the tests

The Clever-Bank Console Application is designed to manage multiple banks, users, accounts, and transactions. It provides core banking functionalities, adheres to SOLID principles, and maintains a clean and organized codebase.

1. Java 17: Ensure you have Java 17 installed.

2. Gradle: The project uses Gradle for build automation. You can install Gradle from here.

3. Docker: You'll need Docker to run PostgreSQL database and Liquibase.

The application supports various banking operations:

• Refill
• Withdraw
• Transfer
• Interest Accrual
• Transaction History
• Account Statements
• Money Statements

1. CRUD Operations: Basic CRUD operations for all entities (Bank, User, Account, Transaction) via Servlets.

2. Configuration: Configuration settings, including interest rates, are stored in a YAML configuration file.

3. Refill and Withdraw: Users can refill and withdraw funds from their accounts in CleverBank.

4. Transfer: Transfer funds between accounts, one or both of which are CleverBank, using a single transaction to achieve thread safety.

5. Interest Accrual: Automatically accrues interest on account balances at the end of each month.

6. Unit Testing: Unit tests covering more than 70% of the codebase, with a focus on service layer testing.

1. Transaction Statements: Generate account or money statements for users in PDF format between two dates. (Statements are saved into $TOMCAT_HOME$/bin/statements directory)

2. Check Generation: Automatically generates check files for every transaction. (Checks are saved into $TOMCAT_HOME$/bin/checks directory)

The endpoint URL is constructed as follows:

• GET /users/{id}
• GET /users
• POST /users
• PUT /users/{id}
• DELETE /users/{id}

• Endpoint: GET /users/{id}
• Example URL: GET /users/12
• Description: Retrieves user information by providing the user's ID as a path parameter.

• Endpoint: GET /users
• Example URL: GET /users?page=1&size=10
• Description: Retrieves a list of users with optional pagination. You can specify the page number (page) and the number of results per page (size) as query parameters.

• JSON Response Example:

  {
    "id": 123,
    "name": "John",
    "surname": "Doe",
    "birthdate": "1990-05-15"
  }
  

• Endpoint: POST /users
• Example Request:

  POST /users
  Content-Type: application/json
  
  {
    "name": "Alice",
    "surname": "Smith",
    "birthdate": "1990-05-15"
  }
  

• JSON Response Example:

    {
    "id": 12,
    "name": "Alice",
    "surname": "Smith",
    "birthdate": "1990-05-15"
    }
  

• Endpoint: PUT /users/{id}
• Example Request:

  PUT /users/123
  Content-Type: application/json
  
  {
    "name": "Updated Name",
    "surname": "Updated Surname",
    "birthdate": "1990-06-20"
  }

• JSON Response Example:

    {
    "id": 123,
    "name": "Updated Name",
    "surname": "Updated Surname",
    "birthdate": "1990-06-20"
    }
  

• Endpoint: DELETE /users/{id}
• Example Request:

  DELETE /users/123
  

Successful Deletion (Status 204 No Content) Description: If the user is successfully deleted, the API responds with a status code of 204 (No Content), indicating a successful deletion. There is no JSON response body in this case.

The endpoint URL is constructed as follows:

• GET /banks/{id}
• GET /banks
• POST /banks
• PUT /banks/{id}
• DELETE /banks/{id}

• Endpoint: GET /banks/{id}
• Example URL: GET /banks/12
• Description: Retrieves bank information by providing the bank's ID as a path parameter.

• Endpoint: GET /banks
• Example URL: GET /banks?page=1&size=10
• Description: Retrieves a list of banks with optional pagination. You can specify the page number (page) and the number of results per page (size) as query parameters.

• JSON Response Example:

    [
    {
    "id": 1,
    "name": "XYZ Bank"
    },
    {
    "id": 2,
    "name": "DEF Bank"
    },
    ...
    ]
  

• Endpoint: POST /banks
• Example Request:

    POST /banks
    Content-Type: application/json
    
    {
    "name": "New Bank"
    }
  

• JSON Response Example:

    {
    "id": 12,
    "name": "New Bank"
    }
  

• Endpoint: PUT /banks/{id}
• Example Request:

    PUT /banks/123
    Content-Type: application/json
    
    {
    "name": "Updated Bank Name"
    }
  

• JSON Response Example:

    {
    "id": 123,
    "name": "Updated Bank Name"
    }
  

• Endpoint: DELETE /users/{id}
• Example Request:

  DELETE /banks/123
  

Successful Deletion (Status 204 No Content): If the bank is successfully deleted, the API responds with a status code of 204 (No Content), indicating a successful deletion. There is no JSON response body in this case.

The endpoint URL is constructed as follows:

• GET /accounts/{id}
• GET /accounts
• POST /accounts
• PUT /accounts/{number}/{transactionType}
• DELETE /accounts/{id}

Input:

• Endpoint: GET /accounts/{id}
• Example URL: GET /accounts/12
• Description: Retrieves account information by providing the account's ID as a path parameter.

Output:

• JSON Response Example:

  {
    "id": 123,
    "number": "1234567890",
    "balance": 1000.0,
    "currency": "USD",
    "userId": 456,
    "bankId": 789,
    "createdDate": "2023-09-01"
  }
  

• Endpoint: POST /accounts
• Example Request:

  POST /accounts
  Content-Type: application/json
  
  {
  "number": "1234567890",
  "balance": 1000.0,
  "currency": "USD",
  "userId": 456,
  "bankId": 789
  }
  

• JSON Response Example:

  {
  "id": 12,
  "number": "1234567890123456",
  "balance": 1000.0,
  "currency": "USD",
  "userId": 1,
  "bankId": 1,
  "createdDate": "2023-09-03"
  }
  

Perform Account Transactions

• Endpoint: PUT /accounts/{number}/{transactionType}
• Example Request:

  PUT /accounts/1234567890123456/withdraw/500
  

Transaction success or failure, depending on the transaction type (withdraw, refill, or transfer). No JSON response body for this operation.

• Endpoint: DELETE /accounts/{id}
• Example Request:

  DELETE /accounts/123
  

Successful Deletion (Status 204 No Content): If the account is successfully deleted, the API responds with a status code of 204 (No Content), indicating a successful deletion. There is no JSON response body in this case.

The endpoint URL is constructed as follows:

• GET /transactions/{id}
• GET /transactions
• POST /transactions

Input:

• Endpoint: GET /transactions/{id}
• Example URL: GET /transactions/12
• Description: Retrieves transaction information by providing the transaction's ID as a path parameter.

Output:

• JSON Response Example:

  {
    "id": 123,
    "amount": 100.0,
    "type": "WITHDRAW",
    "currency": "USD",
    "senderAccountId": 1,
    "receiverAccountId": null,
    "createdDate": "2023-09-03T10:30:00"
  }
  

The Statement Endpoint provides operations for generating account and money statements within specified date ranges.

The endpoint URL is constructed as follows:

• GET /statements/account/{accountNumber}?from={fromDate}&to={toDate}: Generate an account statement within a specified date range.
• GET /statements/money/{userId}?from={fromDate}&to={toDate}: Generate a money transaction statement for a user within a specified date range.

Input:

• Endpoint: GET /statements/account/{accountNumber}?from={fromDate}&to={toDate}
• Example URL: GET /statements/account/123456?from=01-09-2023&to=30-09-2023
• Description: Generates an account statement for the specified account number within the provided date range.

Input:

• Endpoint: GET /statements/money/{userId}?from={fromDate}&to={toDate}
• Example URL: GET /statements/money/456?from=01-09-2023&to=30-09-2023
• Description: Generates a money transaction statement for the specified user ID within the provided date range.

The generated statements is returned in PDF format. The output typically includes details of transactions, balances, and other relevant information.

The project follows a well-organized file structure:

• src/main/java: Contains Java source code.
• src/test/java: Houses unit tests.
• src/main/resources: Stores YAML configuration files.
• databases: Stores Liquibase DB migrations.
• $TOMCAT_HOME$/bin/checks: Stores generated transaction check files.
• $TOMCAT_HOME$/bin/statements/money: Stores generated money statements (PDF).
• $TOMCAT_HOME$/bin/statements/account: Stores generated account statements (PDF).

• Application configuration is managed in YAML file located in src/main/resources.

To run the application:

1. Clone the repository: git clone <repository_url>

2. Configure PostgreSQL settings in application.yml.

3. Build the project: ./gradlew build

4. Run the application: ./gradlew run

./gradlew test