Error executing: CREATE DATABASE aNewDb . Cause: org.postgresql.util.PSQLException: ERROR: CREATE DATABASE cannot run inside a transaction block

Main class where the code is running :

static final String JDBC_DRIVER = "org.postgresql.Driver";
static final String DB_URL = "jdbc:postgresql://localhost:5432/postgres";

//  Database credentials
static final String USER = "postgres";
static final String PASS = "postgres";

public static void main(String[] args) {
    Connection conn = null;
    Statement stmt = null;
    try {
        // STEP 1: Register JDBC driver
        Class.forName(JDBC_DRIVER);

        //STEP 2: Open a connection
        System.out.println("Connecting to database...");
        conn = DriverManager.getConnection(DB_URL, USER, PASS);

        //STEP 3: Execute a query
        ScriptRunner sr = new ScriptRunner(conn);
        //Creating a reader object

        Reader reader = new BufferedReader(new FileReader("C:\\PROJECTS\\SQL\\src\\main\\resources\\createDatabaseAndUser.sql"));

        //Running the script
        sr.runScript(reader);

And this is the file createDatabaseAndUser.sql :

CREATE DATABASE aNewDb;

I am trying to run my program in IDEA and I receive the ERROR :

Connecting to database...
CREATE DATABASE aNewDb
Error executing: CREATE DATABASE aNewDb.
Cause: org.postgresql.util.PSQLException: ERROR: CREATE DATABASE cannot run inside a transaction block

When I run this script without program ( without Main.class ) everything is OK and the database created without any problems.

Copyright Notice：Content Author:「Kuzma」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/60012171/error-executing-create-database-anewdb-cause-org-postgresql-util-psqlexcepti