mysql_jdbc_java

App.java:

package com.NTUC.MavenFirstProject;

/**
 * Hello world!
 *
 */
import java.sql.*;


public class App
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
        System.out.println( "Hello World!" );
        System.out.println( "Hello World!" );
        System.out.println( "Hello World!" );

        App main = new App();

        try {
            main.run();
        } catch (Exception e) {
            System.err.println(e.getMessage());
        }
    }

    private void run() throws SQLException, ClassNotFoundException {
        Class.forName("com.mysql.jdbc.Driver");
        Connection connection = DriverManager.getConnection("jdbc:mysql://localhost/example?user=example&password=example&zeroDateTimeBehavior=convertToNull");
        Statement statement = connection.createStatement();
        ResultSet resultSet = statement.executeQuery("SELECT * FROM example.user");
        System.out.println("Printing schema for table: " + resultSet.getMetaData().getTableName(1));
        int columnCount = resultSet.getMetaData().getColumnCount();

        for (int i = 1; i <= columnCount; i++) {
            System.out.println(i + " " + resultSet.getMetaData().getColumnName(i));
        }

        System.out.println("Searching for example user.");
        boolean exampleUserFound = false;

        while (resultSet.next()) {
            String username = resultSet.getString("name");

            if (username.equals("shiin")) {
                Timestamp createdAt = resultSet.getTimestamp("created_at");
                Timestamp updatedAt = resultSet.getTimestamp("updated_at");
                System.out.println("Example user found.");
                System.out.println("Name: " + username);
                System.out.println("Created at: " + createdAt);
                System.out.println("Updated at: " + updatedAt);
                exampleUserFound = true;

                break;
            }
        }

        if (!exampleUserFound) {
            System.out.println("Example user not found. Inserting a new user.");
            PreparedStatement preparedStatement = connection.prepareStatement("INSERT INTO example.user (name, password, created_at) VALUES (?, ?, ?)");
            preparedStatement.setString(1, "shiin");
            preparedStatement.setString(2, "insecure");
            preparedStatement.setTimestamp(3, new Timestamp(new java.util.Date().getTime()));
            preparedStatement.executeUpdate();
        }

        while (resultSet.next()) {
            String username = resultSet.getString("name");

            if (username.equals("shiin")) {
                Timestamp createdAt = resultSet.getTimestamp("created_at");
                Timestamp updatedAt = resultSet.getTimestamp("updated_at");
                System.out.println("Example user found.");
                System.out.println("Name: " + username);
                System.out.println("Created at: " + createdAt);
                System.out.println("Updated at: " + updatedAt);
                exampleUserFound = true;

                break;
            }
        }




    }
}



mysql -uroot -p -e "DROP DATABASE IF EXISTS example;
CREATE DATABASE example;
GRANT ALL PRIVILEGES ON example.* TO example@localhost IDENTIFIED BY 'example';"


😂/home/tthtlc/mysql/java-mysql-example>cat schema.sql
DROP TABLE IF EXISTS user;

CREATE TABLE user
(
    id INTEGER(10) NOT NULL AUTO_INCREMENT,
    name VARCHAR(64) NOT NULL,
    password VARCHAR(64) NOT NULL,
    created_at TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
    updated_at TIMESTAMP NOT NULL DEFAULT NOW() ON UPDATE NOW(),
    PRIMARY KEY (id)
)