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Driver manager not using the correct driver for the DB url

I have a java application which is able create a connection to multiple DB.
We are loading these drivers:
Class.forName("org.mariadb.jdbc.Driver");
Class.forName("com.treasure_data.jdbc.TreasureDataDriver");
When I try to connect to aurora DB I would expect DriverManager to use the MariaDB driver - but instead it is using treasure_data driver.
java.sql.Connection conn1 = DriverManager.getConnection("jdbc:mysql:aurora://YYY-aurora.XXXXX.com:3306/SomeDBName", "USER", "PASSWORD");
and this is the error I get:
java.sql.SQLException: Invalid JDBC URL: jdbc:mysql:aurora://YYY-aurora.XXXXX.com:3306/SomeDBName. URL prefix must be jdbc:td://
Why is DriverManager using the treasure_data Driver?

The java.sql.DriverManager will ask each registered driver to create a connection with the JDBC url until one driver either returns a (non-null) java.sql.Connection or throws an SQLException.
From JDBC 4.2 section 9.2 The Driver interface:
When the DriverManager is trying to establish a connection, it calls that driver's connect method and passes the driver the URL. If the Driver implementation understands the URL, it will return a Connection object or throw a SQLException if a connection cannot be maded to the database. If the Driver implementation does not understand the URL, it will return null.
From the Driver.connect API doc:
Attempts to make a database connection to the given URL. The driver should return "null" if it realizes it is the wrong kind of driver to connect to the given URL. This will be common, as when the JDBC driver manager is asked to connect to a given URL it passes the URL to each loaded driver in turn.
The driver should throw an SQLException if it is the right driver to connect to the given URL but has trouble connecting to the database.
So a compliant JDBC driver must return null when it is asked to create connection for a JDBC URL it doesn't recognize/support. Only when the URL is supported (eg because the prefix matches the driver), is a driver allowed to throw an SQLException (eg when there is a syntax error in the rest of the JDBC URL, or if the connection cannot be established).
So the com.treasure_data.jdbc.TreasureDataDriver is misbehaving because it throws an SQLException for an URL it doesn't recognise; you need to file a bug report with the author of that driver.

Oracle 12c database connection using thin driver throws IO error

I'm following the JDBC Developer's Guide and trying to test the JDBC thin driver connection using a short java program.
import java.sql.*;
import oracle.jdbc.*;
import oracle.jdbc.pool.OracleDataSource;
class JDBCVersion
{
public static void main (String args[]) throws SQLException
{
OracleDataSource ods = new OracleDataSource();
ods.setURL("jdbc:oracle:thin:hr/hr#localhost:1522:orcl");
Connection conn = ods.getConnection();
// Create Oracle DatabaseMetaData object
DatabaseMetaData meta = conn.getMetaData();
// gets driver info:
System.out.println("JDBC driver version is " + meta.getDriverVersion());
}
} //<host>:<port>:<service>
I've tried every possible <host>:<port>:<service> combination but still get a java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
I've successfully tested the OCI driver using another program included in the tutorial....but can't get this one to work. My application will be using the thin driver to connect to the database so my frustration level is....climbing.
Any help is appreciated.

Maybe following comments could explain why you need the sevice name instead of the SID in the URL.
the Oracle JDBC FAQ mention that SIDs will be cease to be supported in one of the next few releases of the database
the Oracle JDBC devolopers guide mention Always connect to a service. Never use instance_name or SID because these do not direct to known good instances and SID is deprecated
the Oracle 2 day + Java developer tutorial mention the syntax jdbc:oracle:driver_type:[username/password]#//host_name:port_number:SID which seems to be a mixture of SID and service name URL (following the other documents and your working example)
in contrast the javadoc for OracleDriver mention only the SID syntax
the Oracle FAQ wiki mention both syntax
.
jdbc:oracle:thin:[USER/PASSWORD]#[HOST][:PORT]:SID
jdbc:oracle:thin:[USER/PASSWORD]#//[HOST][:PORT]/SERVICE

I'm able to connect to my container DB (containing my tables, packages, etc.) using the username/password.
Returns:
JDBC driver version is 12.1.0.2.0
Still can't connect to the tutorial "HR" PDB that comes with the oracle 12c install and which the JDBC tutorial uses.
Edit:
Got it to work using the following:
import java.sql.*;
import oracle.jdbc.*;
import oracle.jdbc.pool.OracleDataSource;
class JDBCVersion
{
public static void main (String args[]) throws SQLException
{
OracleDataSource ods = new OracleDataSource();
ods.setURL("jdbc:oracle:thin:#//localhost:1522/pdborcl.global.XXXXXXXX.com");
ods.setUser("hr");
ods.setPassword("hr");
Connection conn = ods.getConnection();
// Create Oracle DatabaseMetaData object
DatabaseMetaData meta = conn.getMetaData();
// gets driver info:
System.out.println("JDBC driver version is " + meta.getDriverVersion());
}
}
Still don't understand why I need the full global name instead of the instance name.

When connecting to a PDB you should always use the PDB's service name in the connection string. It looks like your PDB's service is "pdborcl.global.XXXXXXXX.com" so that's what you need to use to connect the PDB directly.
Personally I find it easier to use the long URL format:
"jdbc:oracle:thin:#(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1522))(CONNECT_DATA=(SERVICE_NAME=pdborcl.global.XXXXXXXX.com)))"
It makes it obvious that you're using a Service name instead of an SID.
The beauty of it is that you can also easily test your connection string with sqlplus:
sqlplus "hr/hr#(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1522))(CONNECT_DATA=(SERVICE_NAME=pdborcl.global.XXXXXXXX.com)))"
If sqlplus works there is not reason why the JDBC Thin driver wouldn't.
Finally you can also connect the root database using a privilege user and then execute "ALTER SESSION SET CONTAINER=pdb" to switch to the PDB. Should you decide to do so you would have to modify your connection string to connect to the root container first. It should have its own service name.

Connect to Oracle DB with Java

I am trying to connect to Oracle DB hosted by the faculty.
Given information:
host: bazi.finki.ukim.mk
port: 1521
sid: ORCL
user: xxx
pass: xxx
here is the code:
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection c = DriverManager.getConnection("jdbc:oracle:thin:#bazi.finki.ukim.mk:1521:ORCL","user","pass");
}
catch (Exception e) {
System.out.println(e.getMessage());
}
I get "IO Error: The Network Adapter could not establish the connection"
Also i want to mention that, every group (by the way, this is for project) have workspace... also protected with username and password, even if I can connect into the database, how can i connect to the workspace?
...And also, they wrote that there need to be created tunnel with Putty, is that necessary and how to create it?

This is from http://www.orafaq.com/wiki/JDBC
There are 2 URL syntax, old syntax which will only work with SID and the new one with Oracle service name.
Old syntax
jdbc:oracle:thin:#[HOST][:PORT]:SID
New syntax
jdbc:oracle:thin:#//[HOST][:PORT]/SERVICE
Also note that these 2 lines are unnecessary
Class.forName("oracle.jdbc.driver.OracleDriver");
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
DriverManager will automatically detect the necessary driver by url, see API

How to connect MySQL to Java program

I ve installed MySQL (last update).
I need to code, that ll create & establish a connection with SQL DB
& manage the DB(using SELECT, INSERT, CREATE).
I did everything but, I am not able to create connection. I've also installed the MySQL/J connector, I just extracted the .zip pack in a folder & added the folder path in Variables).
Can anyone tell me wat is meant by URL in the below line?
Connection connection = DriverManager.getConnection(url, username, password);
I ve tried this:
String url = "jdbc:odbc:sqlserver://localhost:3306/myfirstdb";
Connection con = DriverManager.getConnection(url, "root", "1234");
But it's not working. I am unable able to understand the term 'URL'.
Can anyone explain, the meaning of 'url' and wat should be done to connect to a SQL server from Java.
Update:
This is the Full code. It still cannot connect.
import java.sql.*;
public class TestDriver {
public static void main(String[] args) {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");//This s wat actually i did for connection
System.out.println("Driver Loaded Succesfully");
}
catch (Exception e){
System.out.println("Unable to Load Driver!!!");
}
try {
Class.forName(com.mysql.jdbc.Driver"); // initialise the driver
String url ="jdbc:mysql://localhost:3306/myfirstdb";
Connection con = DriverManager.getConnection(url, "root", "1234");
System.out.println("connection Established");
}
catch(Exception e) {
System.out.println("Couldnt get connection");
}
}
}
Can you tell me wat is the purpose of MySQL Connector/J?

In the question you seem to be using a MySQL jdbc driver with a SQL Server jdbc URL. This won't work.
If you are using a MySQL database:
Class.forName("com.mysql.jdbc.Driver"); // initialise the driver
String url ="jdbc:mysql://localhost:3306/myfirstdb";
If you are using a SQL Server database you are going to need a completely different jdbc driver. jTDS is open source and a good option. Include the jtds.jar file in your classpath and use something like:
Class.forName("net.sourceforge.jtds.jdbc.Driver"); // initialise the driver
String url = "jdbc:jtds:sqlserver://localhost:1433/myfirstdb";

Here's an extract from your code:
} catch (Exception e) {
System.out.println("Couldnt get connection");
}
You should never suppress exceptions as long as you don't understand its cause. Replace it by at least:
} catch (Exception e) {
System.out.println("Could not get connection");
e.printStackTrace();
}
Or maybe
} catch (Exception e) {
throw new RuntimeException("Could not get connection", e);
}
Either way, you should see the exception type, message and trace. In your code snippet the possible exceptions are ClassNotFoundException and SQLException. The first one would mean that the driver is not properly placed in the classpath. The second one would mean that connection cannot be obtained. The exception message and/or trace should tell in detail about the underlying root cause of the problem.
You should always observe exceptions. They tell something about the cause of the problem. You know, once a cause is understood, the solution is nothing more than obvious :)
See also:
Short MySQL/JDBC tutorial - Contains explanation about exception causes.
Further,
Can anyone tell me wat is meant by URL in the below line?
An URL is an Uniform Resource Locator. It's a common way to locate (identify) unique resources in computer systems and networks. The URL syntax for the MySQL database is explained in the documentation of the JDBC driver.
Can you tell me wat is the purpose of MySQL Connector/J?
It's the JDBC driver. The JDBC API exist of almost only interfaces. The DB vendors should provide their own concrete JDBC API implementation, which is the JDBC driver. With a JDBC driver you'll be able to connect a specific database using JDBC API.

If its MS SQL Server,
String driver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
Class.forName(driver);
String url = "jdbc:microsoft:sqlserver://host:1433/database";
Connection conn = DriverManager.getConnection(url, "username", "password");
For more info, see this to get started with Microsoft JDBC.
You can use any of the two JDBC drivers for MSSQL:
Microsoft SQL Server JDBC Driver
2.0
jTDS
For MS SQL Server driver 2.0, use
URL: jdbc:sqlserver://server:port; DatabaseName=dbname
Class name: com.microsoft.sqlserver.jdbc.SQLServerDriver
For MySql & Java, see this on SO.

You forgot a " at Class.forName(com.mysql.jdbc.Driver");
It should be
Class.forName("com.mysql.jdbc.Driver");

Help me connecting java and oracle

Can anybody explain me these classes and methods?
DriverManager.registerDriver
(new oracle.jdbc.driver.OracleDriver());
conn = java.sql.DriverManager.getConnection(
"jdb:ocracle:thin:username/password#machine.us.company.com:1234:dbSID");
Thanks

Let's decode the lines of your code block:
1. DriverManager.registerDriver
2. (new oracle.jdbc.driver.OracleDriver());
3. conn = java.sql.DriverManager.getConnection(
4. "jdbc:oracle:thin:username/password#machine.us.company.com:1234:dbSID");
Line 2:
Creates a new instance of oracle.jdbc.driver.OracleDriver, a JDBC Driver for the Oracle database. A JDBC driver implements the interfaces and classes defined by the JDBC API that programmers use to connect to a database and perform queries.
Line 1
Registers the instance of the oracle.jdbc.driver.OracleDriver to the DriverManager class which is the traditional management layer of JDBC, working between the user and the drivers. It handles establishing a connection between a database and the appropriate driver.
Line 3:
Now that the communication layer between the JDBC application and the database is ready, you can create a connection by calling getConnection() method of the DriverManager class.
Line 4:
This is the "connection string" or "database URL". This String identifies the database you want to connect to. The scheme of this URL is specific to the database provider and/or the driver (here, Oracle and its "thin" driver).
Note that prior to Java 6, calling Class.forName was the preferred way to load and register a JDBC Driver. It was the responsibility of the Driver to call DriverManager.registerDriver.
[...] All Driver classes should be written with a static section (a static initializer) that creates an instance of the class and then registers it with the DriverManager class when it is loaded. Thus, a user would not normally call DriverManager.registerDriver directly; it should be called automatically by a Driver class when it is loaded.
Check the Driver Manager chapter from the JDBC documentation for more details.

This is JDBC which is the way Java programs talk to a database, and your sample explicitly asks for the Oracle driver which requires their driver in your classpath.
Sun has a good tutorial on the matter at http://java.sun.com/docs/books/tutorial/jdbc/overview/index.html

The DriverManager class in java handles the connections between the database and the jdbc drivers, routing db i/o to the correct jdbc driver (you can have multiple drivers active ie connections to multiple types of database).
Drivers are registered with the DriverManager so that they become part of its working set. The next step is to create a connection to your database, so you can run queries. This is achived by the
Connection conn = DriverManager.getConnection("jdb:ocracle:thin:username/password#machine.us.company.com:1234:dbSID")
method. The connection String passed into the getConnection() method is driver-specific, you need to RTFM for each driver. Note that the DriverManager selects the driver automatically from its list of registered drivers, according to the syntax of the connection string you pass in.
The Connection object returned is your handle for preparing statements and running queries against the database