Maven CRUD Guide: Database Operations

To implement database CRUD operations using Maven, you will need to add a dependency for the database driver to your Maven project and then write the database operation code. Here is a simple example:

Add the MySQL database driver dependency to the pom.xml file.

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.26</version>
</dependency>

Write Java code for database operations.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DatabaseOperations {

    private static final String URL = "jdbc:mysql://localhost:3306/mydatabase";
    private static final String USER = "username";
    private static final String PASSWORD = "password";

    public void insertData(String name, String email) {
        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD)) {
            String sql = "INSERT INTO users (name, email) VALUES (?, ?)";
            try (PreparedStatement stmt = conn.prepareStatement(sql)) {
                stmt.setString(1, name);
                stmt.setString(2, email);
                stmt.executeUpdate();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public void updateData(int id, String email) {
        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD)) {
            String sql = "UPDATE users SET email = ? WHERE id = ?";
            try (PreparedStatement stmt = conn.prepareStatement(sql)) {
                stmt.setString(1, email);
                stmt.setInt(2, id);
                stmt.executeUpdate();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public void deleteData(int id) {
        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD)) {
            String sql = "DELETE FROM users WHERE id = ?";
            try (PreparedStatement stmt = conn.prepareStatement(sql)) {
                stmt.setInt(1, id);
                stmt.executeUpdate();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public void queryData() {
        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD)) {
            String sql = "SELECT * FROM users";
            try (PreparedStatement stmt = conn.prepareStatement(sql);
                 ResultSet rs = stmt.executeQuery()) {
                while (rs.next()) {
                    int id = rs.getInt("id");
                    String name = rs.getString("name");
                    String email = rs.getString("email");
                    System.out.println("ID: " + id + ", Name: " + name + ", Email: " + email);
                }
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        DatabaseOperations db = new DatabaseOperations();
        db.insertData("Alice", "alice@example.com");
        db.updateData(1, "alice.new@example.com");
        db.deleteData(1);
        db.queryData();
    }
}

This sample code demonstrates how to implement CRUD operations on a database using a Maven project. You will need to modify the URL, USER, and PASSWORD parameters with your own database connection information, and then call different methods to perform the corresponding database operations. In the main method, we create a DatabaseOperations object and call insertData, updateData, deleteData, and queryData methods to execute the respective database operations.