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No suitable driver found error even if the my-sql connector uploaded into the library

I am new to java and in a learning process. I'm working on connecting my JDE with MySql and I have followed every step necessary. but when I run the code, I got " No suitable driver found for jdbc.mysql://localhost:3306/dbname" error. I reviewed questions already in stackoverflow and other sources; but the provided solution didn’t work for me.
Any suggestions why i got this error even if I uploaded the mysql-connector-j-8.0.31/mysql-connector-j-8.0.31.jar.a screenshot of my code and the error message
package JDBC;
import java.sql.SQLException;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.Connection;
public class JDBC {
public static void main(String[] args) throws SQLException{
String url = "jdbc.mysql://localhost:3306/University";
String username = "root";
String password = "root";
String query = "select * from EngineeringStudents";
try {
Class.forName("com.mysql.cj.jdbc.Driver");
}catch(ClassNotFoundException e) {
//To do auto-generated catch block
e.printStackTrace();
}
try {
Connection con = DriverManager.getConnection(url, username, password);
Statement statement = con.createStatement();
ResultSet result = statement.executeQuery(query);
while(result.next()) {
String UniversityData = "";
for(int i = 1; i <= 6; i++) {
UniversityData += result.getString(i) + ":";
}
System.out.println(UniversityData);
}
}catch(SQLException e) {
e.printStackTrace();
}
}
}

Bro use String url = "jdbc:mysql://localhost:3306/University". Use have missed a colon ':' after jdbc instead you're using '.'

JDBC SQL Server errors: ClassNotFound & Not Suitable Driver Found

I am very new to Java and am simply trying to connect to my MSSQL database and return a list of customers. When I try the JDBC connection, I get a "no suitable driver found" error. When I add a Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver") statement, I get a ClassNotFound error. This seems like it should be a lot easier than it's turning out to be. Please help me either find a suitable driver or how to get access through the Class.forName usage.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.ResultSet;
import java.sql.Statement;
public class DbConn {
public static String getConnString(){
return "jdbc:sqlserver://localhost\\SQLEXPRESS:1433;database=OhHold;";
}
public static void getConnection() {
try
{
//Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
String user = "<USER>";
String pw = "****************";
Connection connection = DriverManager.getConnection(getConnString(), user, pw);
Statement statement = connection.createStatement();
String sql = "select txtCompanyName as company from tblCustomers where intNotActive <> 1";
ResultSet result = statement.executeQuery(sql);
while (result.next()) {
System.out.println(result.getString(1));
}
}
/*
// Handle any errors that may have occurred.
catch (ClassNotFoundException e) {
e.printStackTrace();
}
*/
catch (SQLException ex) {
ex.printStackTrace();
}
}
public static void main(String[] args) {
getConnection();
}
}

Connect Oracle Java stored procedure to Snowflake

I was trying to have snowflake db connection using oracle Java stored procedure. But it's giving me error
ORA-29532: Java call terminated by uncaught Java exception: java.sql.SQLException: No suitable driver found
I have already downloaded snowflake-jdbc-3.6.19-javadoc.jar from related source.
Below is sample code of java class which will be called from oracle java procedure.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
public class SnowflakeDriverExample
{
public static void testdata() throws Exception
// public static void main(String[] args) throws Exception
{
// get connection
System.out.println("Create JDBC connection");
Connection connection = getConnection();
System.out.println("Done creating JDBC connectionn");
// create statement
System.out.println("Create JDBC statement");
Statement statement = connection.createStatement();
System.out.println("Done creating JDBC statementn");
// query the data
System.out.println("Query demo");
ResultSet resultSet = statement.executeQuery("SELECT DATA_ID FROM TEMP_TABLE");
System.out.println("Metadata:");
System.out.println("================================");
// fetch metadata
ResultSetMetaData resultSetMetaData = resultSet.getMetaData();
System.out.println("Number of columns=" +
resultSetMetaData.getColumnCount());
statement.close();
}
private static Connection getConnection()
throws SQLException
{
try
{
Class.forName("net.snowflake.client.jdbc.SnowflakeDriver");
}
catch (ClassNotFoundException ex)
{
System.err.println("Driver not found");
}
// Class.forName("net.snowflake.client.jdbc.SnowflakeDriver");
// build connection properties
Properties properties = new Properties();
properties.put("user", "XXX"); // replace "" with your username
properties.put("password", "XXXX"); // replace "" with your password
properties.put("account", "XXXX"); // replace "" with your account name
properties.put("db", "db1"); // replace "" with target database name
properties.put("schema", "MYSCHEMA"); // replace "" with target schema name
//properties.put("tracing", "on");
// create a new connection
String connectStr = null;//System.getenv("SF_JDBC_CONNECT_STRING");
// use the default connection string if it is not set in environment
if(connectStr == null)
{
connectStr = "jdbc:snowflake:XXXX"; // replace accountName with your account name
}
return DriverManager.getConnection(connectStr, properties);
}
}
How to import/integrate this driver for java stored procedure?

Invalid operation for read only resultset when using select for update nowait in multithreaded environment

For an Oracle database, the following program will throw SQL exceptions only for some threads. Why downgrading resultSetConcurrency from CONCUR_UPDATABLE to CONCUR_READ_ONLY? In a single thread environment this is not happening.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class Main extends Thread {
public static final String DBURL = "jdbc:oracle:thin:#localhost:1521:DB";
public static final String DBUSER = "USER";
public static final String DBPASS = "PASS";
public static void main(String[] args) {
// TODO Auto-generated method stub
for(int i=0; i<20; i++)
new Main().start();
}
#Override
public void run() {
try
{
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection con = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
con.setAutoCommit(false);
try(PreparedStatement pstmt = con.prepareStatement("SELECT COLUMN1 FROM TABLE1 FOR UPDATE NOWAIT",
ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE))
{
ResultSet rs = pstmt.executeQuery();
if (rs.next()) {
rs.updateString(1, "12345");
rs.updateRow();
}
}
finally
{
con.commit();
con.close();
}
}
catch(SQLException e)
{
if(!e.toString().contains("NOWAIT"))
e.printStackTrace();
}
}
}

You can look at the warnings raised against the result set/statement/connection to see why it was downgraded. With this added after the executeQuery() call:
SQLWarning warning = pstmt.getWarnings();
while (warning != null)
{
System.out.println("Warning: " + warning.getSQLState()
+ ": " + warning.getErrorCode());
System.out.println(warning.getMessage());
warning = warning.getNextWarning();
}
In this case you'll sometimes see:
Warning: 99999: 17091
Warning: Unable to create resultset at the requested type and/or concurrency level: ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
You're looking for a NOWAIT exception, but you're getting a warning. What isn't clear to me is why you still get a result set in that scenario; but you can at least trap that warning and not go into the result set loop if you see it.

Error while running JDBC on postgres

This is my CreateQuery.java class .
package DbConnect;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class CreateQuery {
Connection conn;
public CreateQuery() throws ClassNotFoundException, SQLException, IOException {
conn=new DbAccess().returnDatabaseConnection();
}
public int addNewLayertoDB(){
try {
PreparedStatement statement = null;
//String table_name = feature_name + "_" + shape;
String query = "SELECT the_geom from bbmp ";
statement = conn.prepareStatement(query);
//statement.setString(1, feature_name);
ResultSet rs = statement.executeQuery();
rs.close();
return 1;
} catch (SQLException ex) {
System.out.println("Sql exception");
return 0;
}
}
public void closeConn() throws SQLException {
if (conn != null) {
this.conn.close();
}
}
public static void main(String args[]) throws FileNotFoundException, IOException, ClassNotFoundException, SQLException{
CreateQuery cq = new CreateQuery();
cq.addNewLayertoDB();
cq.closeConn();
}
}
This is my DbConnect class
package DbConnect;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
public class DbAccess{
public static void main(String[] argv) {
System.out.println("-------- PostgreSQL " +
"JDBC Connection Testing ------------");
try {
Class.forName("org.postgresql.Driver");
} catch (ClassNotFoundException e) {
System.out.println("Where is your PostgreSQL JDBC Driver? " +
"Include in your library path!");
e.printStackTrace();
return;
}
System.out.println("PostgreSQL JDBC Driver Registered!");
Connection connection = null;
try {
connection = DriverManager.getConnection(
"jdbc:postgresql://127.0.0.1:5432/Ethermap","postgres", "*******");
} catch (SQLException e) {
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
return;
}
if (connection != null){
System.out.println("You made it, take control your database now!");
}else{
System.out.println("Failed to make connection!");
}
}
public Connection returnDatabaseConnection() {
System.out.println("DB not connected");
return null;
}
}
The error I am getting when I run CreateQuery is
DB not connected
Exception in thread "main" java.lang.NullPointerException
at DbConnect.CreateQuery.addNewLayertoDB(CreateQuery.java:24)
at DbConnect.CreateQuery.main(CreateQuery.java:45)
What is the error ? And How do I debug it ?

The method returnDatabaseConnection() that you call in the constructor of CreateQuery always returns null, so it's not a surprise that your connection object is null.