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Local and Remote connection pools, Java DBCP

I have the following use-case:
I have a system that needs to use two different connection pools, One is for 'local' database (Meaning a database running on the local machine) and the other one is a 'remote' database. (Meaning a database that is running on a remote different server)
The remote database is a configuration sharing database, while the local one is has different kinds of data.
I've created two classes in order to connect to those datababase:
public class ConnectionPool {
private static BasicDataSource ds = createNewDatasource();
private static BasicDataSource createNewDatasource() {
BasicDataSource ds = new BasicDataSource();
String url = "jdbc:mysql://127.0.0.1:3306/SOME_DB"
ds.setUrl(url);
ds.setUsername(...);
ds.setPassword(...);
return ds;
}
public static Connection getConnection() throws SQLException {
return ds.getConnection();
}
}
The other class looks exactly the same, Only it's called RemoteConnection and the url is changed to:
String url = "jdbc:mysql://<REMOTE_IP>:3306/SOME_DB_2"
Running the above classes, I keep receiving the following message in my logs:
ERROR (RemoteConnection.java:40) - Failed on getConnection
java.sql.SQLException: Cannot create PoolableConnectionFactory (Access denied for user '...'#'<MACHINE_LOCAL_IP>' (using password: YES))
at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2291)
at org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:2038)
at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1533)
at Censored.RemoteConnection.getConnection(RemoteConnection.java:59)
...
Caused by: java.sql.SQLException: Access denied for user '...'#'<MACHINE_LOCAL_IP>' (using password: YES)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:873)
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1710)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1226)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2188)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2219)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2014)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:776)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.GeneratedConstructorAccessor31.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:57)
at java.lang.reflect.Constructor.newInstance(Constructor.java:437)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
at org.apache.commons.dbcp2.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:39)
at org.apache.commons.dbcp2.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:256)
at org.apache.commons.dbcp2.BasicDataSource.validateConnectionFactory(BasicDataSource.java:2301)
at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2287)
...
Firstly, The error above is weird. I've never used the machine local IP. So I don't understand where it came from. In addition, It doesn't seems like a privilege problem since I've tried logging into remote database through cli, using:
mysql -u'...' -p'...' -h <REMOTE_IP> SOME_DB_2
And it connected successfully. It smells to me like a JDBC Driver or connection definition problem but I can't seem to find the problematic spot.
Any idea what I'm doing wrong?

I've found the problem. It was an SSL issue.
The user I've used had to connect with SSL certificate.
That's also the reason why I've seen the local machine IP in the error.
A way to check is:
Select * from mysql.user where user='...';
What I've found was that:
ssl_type != ''
So I had to define:
jdbc:mysql://<REMOTE_IP>:3306/SOME_DB_2&useSSL=true
Configure the relevant certificates, and all was well.

Issue connecting to sql database from eclipse project? [duplicate]

I am trying to connect with database using jdbc in java file. It is not connecting at all and giving me the error constantly "Something went wrong"; I guess it is because of the port number because all other data such as username, password and other code seems correct.
I want to check the default port number so that I can try it properly. I did try using all three of these 8080, 80 and 3306 but it shows me error.
Here port 8080 is used for HTTP server, 3306 is supposed to be default from the research and 80 randomly.
try {
Class.forName("com.mysql.jdbc.Driver");
System.out.println("Driver found");
} catch (ClassNotFoundException e) {
System.out.println("Driver not found");
}
String url="jdbc:mysql://localhost:8080 or 80 or 3306 or without port number/test";
String user="user";
String password="";
Connection con=null;
try {
con=DriverManager.getConnection(url, user, password);
System.out.println("Success");
} catch (SQLException e){
e.printStackTrace();
}
}
The error is giving below when used String url="jdbc:mysql://localhost:3306/test";
Driver found
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1036)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:338)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2232)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2265)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2064)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:790)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at com.town.connect.Dbconnection.main(Dbconnection.java:26)
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:382)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:241)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:228)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:431)
at java.net.Socket.connect(Socket.java:527)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:213)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:297)
... 15 more

You can access those settings via
mysql> show variables;

DriverManager.getConnection("jdbc:mysql://"+dbaddress+"/"+dbname+"?user=" + username + "&password=" + password)
This statement can help you. No need to define any other port. Just define the following variables as per your mysql configuration.
dbaddress
dbname
username
password
And if this doesn't works can you post the stacktrace or a screenshot for your error ?

If you want to know the port number you can use following command
SHOW VARIABLES WHERE Variable_name = 'port';

Getting connection time out while running Oozie workflow through Java

I am getting following error when i try to run Oozie workflow using java
IO_ERROR : java.net.ConnectException: Connection timed out: connect
at org.apache.oozie.client.OozieClient.validateWSVersion(OozieClient.java:234)
at org.apache.oozie.client.OozieClient.createURL(OozieClient.java:300)
at org.apache.oozie.client.OozieClient.access$000(OozieClient.java:71)
at org.apache.oozie.client.OozieClient$ClientCallable.call(OozieClient.java:366)
at org.apache.oozie.client.OozieClient.run(OozieClient.java:547)
at oozieDemo.main(oozieDemo.java:27)
Caused by: java.net.ConnectException: Connection timed out: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
Here is my code:
OozieClient wc = new OozieClient("http:xxxxxxx/oozie");
System.out.println(" connection established....." + wc);
Properties conf = wc.createConfiguration();
conf.setProperty(OozieClient.APP_PATH,"hdfs:foo/xxx/workflow.xml");
conf.setProperty("jobTracker", "foo:8021");
conf.setProperty("nameNode","hdfs:xxxx");
conf.setProperty("queueName", "default");
conf.setProperty("appLibLoc","hdfs:/foo/xxx/lib");
String jobId = wc.run(conf);
System.out.println("Workflow job submitted");
So here I can see connection is getting established but unable to run the workflow.
I am new to this. So can't figure it out where exactly it is failing.

Connection timeout means either:
URL is incorrect or down, try pinging it.
Firewall is blocking it.
Default timeout expired.
Your internet access is down, which I'm going to assume isn't the case.

Unable to connect to MySQL on localhost from a Java program on Ubuntu

Following is the code.
import java.sql.*;
public class ActivityReader {
public static void main(String[] args) {
System.out.println("MySQL Connect Example.");
Connection conn = null;
String url = "jdbc:mysql://localhost:3306/";
String dbName = "jdbctutorial";
String driver = "com.mysql.jdbc.Driver";
String userName = "root";
String password = "password";
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
conn = DriverManager.getConnection(url,userName,password);
System.out.println("Connected to the database");
conn.close();
System.out.println("Disconnected from database");
} catch (Exception e) {
e.printStackTrace();
}
}
}
I have already added mysql-connector-java-5.1.20-bin.jar in project from this url.
Mysql service is already running.
mysql start/running, process 25326
MySQL Connect Example.
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:348)
at c
om.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2391)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2428)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2213)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:797)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at ActivityReader.main(ActivityReader.java:45)
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
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.<init>(Socket.java:375)
at java.net.Socket.<init>(Socket.java:218)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:257)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:298)
... 15 more
Any idea.... ??????

Connect using 127.0.0.1 instead localhost, maybe a clue of what is happening on your system:
MySQL will try to connect to the unix socket if you tell it to connect
to "localhost". If you tell it to connect to 127.0.0.1 you are forcing
it to connect to the network socket. So probably you have MySQL
configured to only listen to the network socket and not to the file
system socket.
https://serverfault.com/questions/295285/mysql-cannot-connect-via-localhost-only-127-0-0-1

try
>telnet localhost 3306
You are supposed to see some server response similar to
"5.5.19☺(:*b2p`p!☻ǧ4Oph7xxsV5C5mysql_native_password"
Most probably problem will be fixed by replacing hostname with ip, check https://serverfault.com/a/90055

I think you are not specified your db name in your connection URL try this conn = DriverManager.getConnection(url +"/"+ dbName ,userName,password); And be sure that you have created the database with same name.

I face the same issue on a VPS linux server. I solve it by replacing localhost or 127.0.0.1 by the real IP address.

If you are trying to run your code on a Linux Machine or Windows Server.
You can change the server from 'localhost' to specific IP 'xx.xx.xx.xx'
and it should work fine.

Can't make JDBC connection to MySQL (using Java, IntelliJ, and Linux)

I am having issues trying to get a database connection using the code below:
try {
Class.forName("com.mysql.jdbc.Driver");
Properties p = new Properties();
p.put("user", user_name);
p.put("password", password);
connection = DriverManager.getConnection("jdbc:mysql://127.0.0.1/jsp_test", p);
} catch (SQLException ex) {
// handle any errors
ex.printStackTrace();
System.out.println("SQLException: " + ex.getMessage());
System.out.println("SQLState: " + ex.getSQLState());
System.out.println("VendorError: " + ex.getErrorCode());
return false;
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
The error message that is outputted is:
/usr/lib/jvm/java-6-openjdk/bin/java
-Didea.launcher.port=7532 -Didea.launcher.bin.path=/usr/bin/idea/bin
-Dfile.encoding=UTF-8 -classpath /usr/lib/jvm/java-6-openjdk/jre/lib/jce.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/about.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/resources.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/management-agent.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/jsse.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/charsets.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/rt.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/ext/localedata.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/ext/sunjce_provider.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/ext/sunpkcs11.jar:/usr/lib/jvm/java-6-openjdk/jre/lib/ext/dnsns.jar:/home/bedtimes/Java
Projects/db_demo/out/production/db_demo:/opt/java/jre/lib/ext/mysql-connector-java-5.1.10-bin.jar:/usr/bin/idea/lib/idea_rt.jar com.intellij.rt.execution.application.AppMain
Main
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:
Communications link failure
The last packet sent successfully to
the server was 0 milliseconds ago. The
driver has not received any packets
from the server. at
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method) at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at
java.lang.reflect.Constructor.newInstance(Constructor.java:532)
at
com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at
com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at
com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2214)
at
com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:781)
at
com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:46)
at
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method) at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at
java.lang.reflect.Constructor.newInstance(Constructor.java:532)
at
com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at
com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352)
at
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:284)
at
java.sql.DriverManager.getConnection(DriverManager.java:620)
at
java.sql.DriverManager.getConnection(DriverManager.java:169)
at
database.Database.connect(Database.java:80)
at Main.main(Main.java:13) at
sun.reflect.NativeMethodAccessorImpl.invoke0(Native
Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at
java.lang.reflect.Method.invoke(Method.java:616)
at
com.intellij.rt.execution.application.AppMain.main(AppMain.java:110)
Caused by:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:
Communications link failure
The last packet sent successfully to
the server was 0 milliseconds ago. The
driver has not received any packets
from the server. at
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method) at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at
java.lang.reflect.Constructor.newInstance(Constructor.java:532)
at
com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at
com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at
com.mysql.jdbc.MysqlIO.(MysqlIO.java:343)
at
com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2137)
... 18 more Caused by:
java.net.ConnectException: Connection
refused at
java.net.PlainSocketImpl.socketConnect(Native
Method) at
java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:310)
at
java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:176)
at
java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:163)
at
java.net.SocksSocketImpl.connect(SocksSocketImpl.java:384)
at
java.net.Socket.connect(Socket.java:542)
at
java.net.Socket.connect(Socket.java:492)
at
java.net.Socket.(Socket.java:389)
at
java.net.Socket.(Socket.java:232)
at
com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253)
at
com.mysql.jdbc.MysqlIO.(MysqlIO.java:292)
... 19 more SQLException:
Communications link failure
The last packet sent successfully to
the server was 0 milliseconds ago. The
driver has not received any packets
from the server. SQLState: 08S01
VendorError: 0
Process finished with exit code 0
I've, literally, no idea how to troubleshoot this error message. The database exists. The username and password exists. I've currently not added any tables to the database but I don't think that can be the issue, since I'm only making a connection after all...
I can provide extra information if needs be. I feel like I've tried a lot. Does anybody know any ways of getting further information on how and why it's failing?
Thanks for your help! :)

From your connection string, this database should be on the local machine. Can you try running this command to ensure the socket is open for connections?
telnet 127.0.0.1 3306
and ensure that it connects? You may not have configured your mysql instance to listen for connections from this machine or on this interface address. If the connection fails, you need to modify your mysql config, for example:
http://www.cyberciti.biz/tips/how-do-i-enable-remote-access-to-mysql-database-server.html

I had the same symptoms but for me the solution was to change the bind-address to 0.0.0.0 in /etc/mysql/my.cnf
(Just posting this for others seeking an answer to this question)

You can try this instead:
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/jsp_test","user_name","password");

you can try one of the following
"jdbc:mysql://localhost:3306/jsp_test","username","password"
or
"jdbc:mysql://'your machines ip (without quote)':3306/jsp_test","username","password"
or
"jdbc:mysql://127.0.0.1:3306/jsp_test","username","password"
as a connection string.