package org.kodejava.example.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;

public class SystemFunction {
    private static final String URL = "jdbc:mysql://localhost/kodejava";
    private static final String USERNAME = "root";
    private static final String PASSWORD = "";

    public static void main(String[] args) {
        try (Connection connection =
                 DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
            DatabaseMetaData meta = connection.getMetaData();

            // Get system functions supported by database
            String[] functions = meta.getSystemFunctions().split(",\\s*");

            for (String function : functions) {
                System.out.println("Function = " + function);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

Here are MySQL database supported system functions.

Function = DATABASE
Function = USER
Function = SYSTEM_USER
Function = SESSION_USER
Function = PASSWORD
Function = ENCRYPT
Function = LAST_INSERT_ID
Function = VERSION

Maven dependencies

<!-- https://search.maven.org/remotecontent?filepath=mysql/mysql-connector-java/8.0.17/mysql-connector-java-8.0.17.jar -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.17</version>
</dependency>