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JDBC driver error and cannot connect to MySQL [duplicate]

This question already has answers here:
Connect Java to a MySQL database
(14 answers)
What is a classpath and how do I set it?
(10 answers)
Closed 5 months ago.
I keep getting the error messages when I run my code attempting to connect to a MySQL server
Exception in thread "main" java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:375)
This is my code. I've made sure to add connector/J to the classpath and still no change.
import java.sql.*;
public class App {
public static void main(String[] args) throws Exception {
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/vehicle", "root", "root"); // For MySQL only
vehicle focus = new vehicle("Ford", "Focus", 200, 2004, 3000);
System.out.println(focus.getMake());
}
}

First of all, loading the JDBC driver using Class.forName is not necessary since JDBC 4.0 which was made available in 2006 (the driver registers its implementation as service provider and will be loaded by the ServiceLoader).
Just remove this line and it should work. If you need the class name, its a good idea to consult the documentation of Connector/J. Take care to read the docs for the correct driver version because the class name changed (currently it's com.mysql.cj.jdbc.Driver).
Update
As Mark Rotteveel pointed out, Class.forName("com.mysql.jdbc.Driver") will not lead to a ClassNotFoundException when used with newer version of Connector/J. At least the newest driver produces a warning:
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new
driver class is `com.mysql.cj.jdbc.Driver'. The driver is
automatically registered via the SPI and manual loading of the driver
class is generally unnecessary.
Knowing this, removing Class.forName won't help since the exception simply means, that the driver is not on the class path.

No native library for SQLite JDBC in Windows

The problem is that JDBC won't connect to the database saying that there is no native SQLite library.
Problem method:
public static void connect() throws SQLException, ClassNotFoundException {
Class.forName("org.sqlite.JDBC");
connection = DriverManager.getConnection("jdbc:sqlite:" + $appRoot + "\\data\\db\\sqlite\\users.sqlite");
statement = connection.createStatement();
statement.executeQuery("SELECT * FROM users");
}
Error:
Exception in thread "main" java.sql.SQLException: Error opening connection
at org.sqlite.SQLiteConnection.open(SQLiteConnection.java:239)
at org.sqlite.SQLiteConnection.<init>(SQLiteConnection.java:61)
at org.sqlite.jdbc3.JDBC3Connection.<init>(JDBC3Connection.java:28)
at org.sqlite.jdbc4.JDBC4Connection.<init>(JDBC4Connection.java:21)
at org.sqlite.JDBC.createConnection(JDBC.java:115)
at org.sqlite.JDBC.connect(JDBC.java:90)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:251)
...
Caused by: java.lang.Exception: No native library found for os.name=Windows, os.arch=x86_64, paths=[C:\Program Files\Java\jdk-15.0.2\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;E:\Program Files\gcc\bin;E:\Program Files\gcc\libexec\gcc\x86_64-w64-mingw32\8.3.0;C:\Program Files\Common Files\Oracle\Java\javapath;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\nodejs\;E:\Program Files\Maven\bin;E:\Program Files\PuTTY\;C:\Program Files\Git\cmd;C:\Users\Lenovo\AppData\Local\Microsoft\WindowsApps;C:\Users\Lenovo\AppData\Roaming\npm;E:\Program Files\IntelliJ IDEA 2020.3.3\bin;E:\Program Files\WebStorm 2020.1\bin;C:\Gradle\gradle-6.7.1\bin;C:\Users\Lenovo\AppData\Local\Programs\Microsoft VS Code\bin;C:\Program Files\heroku\bin;.]
at org.sqlite.SQLiteJDBCLoader.loadSQLiteNativeLibrary(SQLiteJDBCLoader.java:367)
at org.sqlite.SQLiteJDBCLoader.initialize(SQLiteJDBCLoader.java:67)
at org.sqlite.core.NativeDB.load(NativeDB.java:63)
at org.sqlite.SQLiteConnection.open(SQLiteConnection.java:235)
... 10 more
Platform: win x86-x64

Add this in your build file
kapt "org.xerial:sqlite-jdbc:3.34.0"
Check out this thread for details.

Java issue within connection to Microsoft SQL Server

How can I connect to Microsoft SQL Server from my java code?
Code:
public class insert {
public static void main(String[] args) {
try {
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
String url = "jdbc:microsoft:sqlserver://LENOVO-PC\\SQLEXPRESS;DatabaseName=dbtest";
Connection connection = DriverManager.getConnection(url , "sa" , "Aa123456");
Statement st = connection.createStatement();
st.executeUpdate("INSERT INTO [dbo].[table] VALUES ('come')");
}
catch (ClassNotFoundException e)
{
e.printStackTrace();
System.exit(1);
}
catch (SQLException e)
{
e.printStackTrace();
System.exit(2);
}
}
}
Error:
java.lang.ClassNotFoundException: com.microsoft.jdbc.sqlserver.SQLServerDriver
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at insert.main(insert.java:12)
Microsoft SQL Server name is: LENOVO-PC\SQLEXPRESS
and sqljdbc.jar is already added to the referenced libraries.

The class name com.microsoft.jdbc.sqlserver.SQLServerDriver you're trying to load is from a very old version of the Microsoft SQL Server 2000 version of the driver. Around 2005, Microsoft changed this to com.microsoft.sqlserver.jdbc.SQLServerDriver (notice the switch in order between jdbc and sqlserver). At that time, they also changed the driver URL prefix from jdbc:microsoft:sqlserver: to jdbc:sqlserver:.
In other words, you need to:
Use Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver") (optional, driver will be loaded automatically)
Change your URL to jdbc:sqlserver://LENOVO-PC\\SQLEXPRESS;databaseName=dbtest (note the prefix change and DatabaseName -> databaseName. See also Building the Connection URL.
With recent JDBC drivers, it is not necessary to explicitly load the driver class in simple Java applications, so instead of step 1, you could also remove the Class.forName line.
Also make sure you are using a recent version of the driver, see the mssql-jdbc project on GitHub (latest stable version at time of writing is 7.0.0).

Correct the driver class name:
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

Error in connecting to AS400 DB2 server JDBC

I am trying to connect to the AS400 DB2 database using the JDBC in a java program but I am unable to connect as it is giving a SQLException stating No suitable driver found for ​jdbc:as400://192.168.1.11
Whereas I added No suitable driver found for ​jdbc:as400://192.168.1.11
I added the following libraries to my project: db2jcc_licence_cu.jar, db2jcc4.jar, jt400-6.4.jar.
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
public class ReadAllTables {
public static void main(String args[]) throws Exception {
//Class.forName ("com.ibm.as400.access.AS400JDBCDriver");
DriverManager.registerDriver(new com.ibm.as400.access.AS400JDBCDriver());
// Enable logging
// DriverManager.setLogStream(System.err);
System.out.println("Getting Connection");
Connection c = DriverManager.getConnection ("​jdbc:as400://ipaddress","username","password");
DatabaseMetaData md = c.getMetaData();
ResultSet rs = md.getTables(null, null, "%", null);
while (rs.next()) {
System.out.println(rs.getString(3));
}
}
}
This is what the error I am getting:
Getting Connection
Exception in thread "main" java.sql.SQLException: No suitable driver found for ​jdbc:as400://192.168.1.11
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.test.ReadAllTables.main(ReadAllTables.java:18)
Thanks in advance

You must have jt400.jar in your classpath for the AS/400 JDBC driver to work.
Version 7.10 is in Maven or download the latest from https://sourceforge.net/projects/jt400/ or copy it from IFS. The native CC driver is only used when running locally on the AS/400.
Given your current list of jars it sounds like your CLASSPATH variable is incorrect (or if you use a runnable jar, your Class-Path line in the manifest file is wrong). If you launch with RUNJVA the mechanism is different.

getting class not found exception

Hi friends i am facing the following error while trying to connect to a database through java code:
Exception in thread "Main Thread" java.lang.ClassNotFoundException: oracle.jdbc.OracleDriver
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at com.example.model.Driver.main(Driver.java:13)
My java code is:
package com.example.model;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Driver {
public static void main(String args[]) throws ClassNotFoundException,
SQLException {
Class.forName("oracle.jdbc.OracleDriver");
// or you can use:
// DriverManager.registerDriver(
// new oracle.jdbc.driver.OracleDriver());
Connection conn = DriverManager.getConnection(
"jdbc:oracle:thin:#127.0.0.1:1521:ORCL", "scott", "tiger");
Statement stmt = conn.createStatement();
ResultSet rset = stmt.executeQuery("select * from customer");
while (rset.next())
System.out.println(rset.getString(1));
rset.close();
stmt.close();
conn.close();
}
}
As per i came to know it could be due to class path issue but don't know how to resolve it.
I set my class path to
C:\bea\user_project\workspace\wlserver_10.3\server\ext\jdbc\oracle\11g\ojdbc5.jar;
I am using weblogic 10.3 workspace and weblogic 10.3 server.

The java.lang.ClassNotFoundException: oracle.jdbc.OracleDriver definitely means that the mentioned class is not on the class path. And because ojdbc5.jar has it, the whole question is: "how did you set your classpath"?
Here is what I get on my machine using your code (using the default package):
$ cat > Driver.java
...
$ javac Driver.java
$ java -cp /home/pascal/opt/Oracle/Middleware/wlserver_10.3/server/ext/jdbc/oracle/11g/ojdbc5.jar:. Driver
Exception in thread "main" java.sql.SQLException: The Network Adapter could not establish the connection
at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:131)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:197)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:525)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:413)
at oracle.jdbc.driver.PhysicalConnection.(PhysicalConnection.java:508)
at oracle.jdbc.driver.T4CConnection.(T4CConnection.java:203)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:33)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:510)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at Driver.main(Driver.java:15)
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:328)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:421)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:634)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:208)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:966)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:292)
... 7 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at java.net.Socket.(Socket.java:375)
at java.net.Socket.(Socket.java:189)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:127)
at oracle.net.nt.ConnOption.connect(ConnOption.java:126)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:306)
... 12 more
The driver is found (I get an exception because I'm not running any Oracle server but this is another story).

I will try to put it in the weblogic's lib folder... and restart the server, so you will be sure that it is a classpath problem...
You should download the oracle drivers from oracle and put the .jar file in the project's CLASSPATH...
You can download it at Oracle's drivers download page