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Code showing username and password for connecting to server

I'm writing a method that make it possible for my Java program to create a database connection that will eventually make me able to access it from other classes/methods.
public class DatabaseConnection
{
private Connection databaseLink;
public Connection getConnection()
{
String url = "jdbc:mysql://localhost/DBname";
try
{
Class.forName("com.mysql.cj.jdbc.Driver");
databaseLink = DriverManager.getConnection(url, "fakeUsr", "fakePsw"); //these are not the real username/password
}
catch (Exception e)
{
e.printStackTrace();
}
return databaseLink;
}
}
I've got a couple of issues:
1)people not using my computer will not be able to get into my server since I wrote "localhost":
String url = "jdbc:mysql://localhost/DBname";
2)I've typed the real username and password instead of "fakeUsr" and "fakePsw".
The thing is: I'm quite sure that the average user of my program should NOT be able to access that information. Is there any other way to permit access to a DB without making username and password readable by virtually anyone getting access to my source code?
For issue n. 1: I tried to type my IP address instead of "localhost" here:
String url = "jdbc:mysql://localhost/DBname"; //changed localhost to my IP address
but then I get "Communications link failure".
For issue n. 2: I have literally no idea how to solve this. I've never coded a program that needs access to a DB so I had to improvise a bit for that.

About Issue #2:
There is no secure way of storing the password inside the code itself. You can of course try to encrypt the password, but then your code has to decrypt it when the connection is established and therefore the encryption key is visible virtually "to all that have access to your source code". With this key, it is possible to get to the real password, just a little bit more complicated.
The only secure way is to have the user enter the login credentials by his own. Either low level (program arguments when starting your application) or by some form of "login dialog", if the application has a GUI.
A third option would be to create a technical user with restricted DB access, depending on the application you are working on. But this usually causes security issues.

You could create your application such that it sends an https request and authenticate itself against a webserver. What you use to authenticate is up to you: Client IP, username, password, client certificates, ...
Once authenticated, your webserver could transfer a one-time username/password that the client uses to login into your database.
The advantage here is that you can still control whether the user gets full or restricted access, or gets no password any more for whatever reason. And there is no security hole in your application.

1⁠) Most Internet providers don’t allow ordinary users to accept incoming socket connections, both for security reasons and because the network traffic can quickly overwhelm consumer grade networks. You will have to either purchase a commercial Internet connection which allows incoming connections, or look for a server you can lease or borrow. I’m afraid I don’t know what options are available.
2⁠) As MrFreeze correctly pointed out, there is no way to safely embed credentials in an application. No matter what you do to obscure your database login credentials, someone can always decompile your program and figure out how you are decrypting those credentials. The only truly safe solution is to tell users you trust what the credentials are, then write your application so the user must enter them.
Side note: Class.forName("com.mysql.cj.jdbc.Driver"); has not been needed for many years. You can remove that line.

PCFMessageAgent - Authentication

How does the PCFMessageAgent with the following constructor gets authenticated. What are the user/configuration permissions required to be set. I connect to MQ of version 8.0.0.4.
public PCFMessageAgent(java.lang.String host,
int port,
java.lang.String channel)
throws MQException

You do not provide enough details to give an exact answer. That constructor does not allow for authentication, it connects to the host/port/channel specified but does not pass a username/password or allow for the use of a cetificate.
If the channel on the queue manager does not require CONNAUTH (ex: "CHKCLNT(OPTIONAL)") or TLS (ex: SSLCIPH/SSLPEER) and you are not blocked by CHLAUTH rules, you may be able to connect.
To determine what user MQ would use for authorization would depend on what user your java process is running under, the MCAUSER attribute of the channel, and any CHLAUTH rules that could map you to a different MCAUSER. Based on the final MCAUSER value, MQ would check if you have permission to the SYSTEM.ADMIN.COMMAND.QUEUE and the model queue used to create a temporary dynamic queue for replies.
If you want to provide a username and password or use certificates you would need to create a MQQueueManager and pass this instead of host/port/channel using this constructor:
PCFMessageAgent(MQQueueManager qmanager)
Initializes a new PCFMessageAgent with an existing queue manager connection.

Access denied for User 'root'#'localhost' (using password: YES )

I would like to connect with my local MYSQL data base, which is installed along with XAMP server. I created a new User ie, " NewUser " and its password is "password". I given all PRIVILEGES to this user.
I write the code to connect with data base by using user "root" (No password for this user).
Its connected . Like bellow..
return DriverManager.getConnection("jdbc:MySql://localhost/database_name","root","");
Now I wrote the code to connect with same data base by another user ie, "NewUser" and its pasword "password"
return DriverManager.getConnection("jdbc:MySql://localhost/database_name","NewUser","password");
but its not connected.
The error in console is
java.sql.SQLException: Access denied for user 'NewUser'#'localhost' (using password: YES)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1074)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4120)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4052)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:925)
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1704)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1250)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2465)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2498)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2283)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:822)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.GeneratedConstructorAccessor207.newInstance(Unknown Source)
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:404)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:317)
at org.eclipse.datatools.connectivity.drivers.jdbc.JDBCConnection.createConnection(JDBCConnection.java:214)
at org.eclipse.datatools.connectivity.DriverConnectionBase.internalCreateConnection(DriverConnectionBase.java:105)
at org.eclipse.datatools.connectivity.DriverConnectionBase.open(DriverConnectionBase.java:54)
at org.eclipse.datatools.connectivity.drivers.jdbc.JDBCConnection.open(JDBCConnection.java:73)
at org.eclipse.datatools.enablement.internal.mysql.connection.JDBCMySQLConnectionFactory.createConnection(JDBCMySQLConnectionFactory.java:28)
at org.eclipse.datatools.connectivity.internal.ConnectionFactoryProvider.createConnection(ConnectionFactoryProvider.java:83)
at org.eclipse.datatools.connectivity.internal.ConnectionProfile.createConnection(ConnectionProfile.java:359)
at org.eclipse.datatools.connectivity.ui.PingJob.createTestConnection(PingJob.java:76)
at org.eclipse.datatools.connectivity.ui.PingJob.run(PingJob.java:59)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:53)
I give the host type while providing PRIVILEGES to this user, as " any host" ie."%".
If I change this to " localhost " or "127.0.0.1" its working.
So How can i use my database with " anyhost " PRIVILEGES to the particular user like "NewUser" .
If I got success here then I successes in connection to client live Data base..
Thanks to all and please let me out from this one.....

Since the first specified code works and also based on the reported trace, i'm pretty sure the problem is on the database, not the code syntax.
Based on the Mysql version, please try as an alternative to set privileges without specifying the any host (%) as based on Mysql documentation,
The simple form user_name is a synonym for user_name#'%'
Also flush privileges immediately after using FLUSH PRIVILEGES;
Just to make sure everything is correct, also run a
SHOW GRANTS FOR NewUser; and check if NewUser appears in the list with the corresponding permissions.

your URL is meant to be all lowercase -- `jdbc:MySql://localhost/database_name"
Is your database really called database_name?

Please try this syntax
return DriverManager.getConnection("jdbc:mysql://localhost/database_name?user=NewUser&password=your_password_here");
(just replace your password where it says "your_password_here")
EDIT - SECOND GUESS:
Its possible you have firewalled yourself by blocking 192.168.x.x range.
i assume you running windows. open up command prompt, type "ipconfig" press enter. see your ipv4 adress (should be something like 192.168.1.x)
Be sure your antivirus/firewall program permits connection from 192.168.1.x (which is yourself) and then try using that instead of "%" or "localhost"
If this doesn't work, close all your firewall/antivirus and try again.
Also try reloading privileges either by:
restarting xampp
FLUSH PRIVILEGES;

In order to give users access to your database, you need to specify a host where they should be allowed to connect from.
But please be careful: Even if you use a wildcard (%) as the host name, the user cannot connect from localhost. They can connect from ANY host, but not from localhost.
When connecting from localhost, I assume your mysql installation assumes you to be an anonymous user.
In order to allow a user to connect from localhost, you need to add a separate user whith "localhost" in the host field.
For more details, please refer to the MySQL documentation
Two of the accounts have a user name of monty and a password of
some_pass. Both accounts are superuser accounts with full privileges
to do anything. The 'monty'#'localhost' account can be used only when
connecting from the local host. The 'monty'#'%' account uses the '%'
wildcard for the host part, so it can be used to connect from any
host.
It is necessary to have both accounts for monty to be able to connect
from anywhere as monty. Without the localhost account, the
anonymous-user account for localhost that is created by
mysql_install_db would take precedence when monty connects from the
local host. As a result, monty would be treated as an anonymous user.
The reason for this is that the anonymous-user account has a more
specific Host column value than the 'monty'#'%' account and thus comes
earlier in the user table sort order. (user table sorting is discussed
in Section 6.2.4, “Access Control, Stage 1: Connection Verification”.)

GO to users/privileges/edit privileges/
change password or select no password
update the password in hibernate config file and restart the server.

JDBC MySQL connection without specifying password

Is it possible to connect to a MySQL database without specifying the username and password in Java code :
Connection con=DriverManager.getConnection("database url","username","password");
or is there any way to change the username and password using Java?

There is another method of the same name to connect anonymously (without username or password):
Connection con=DriverManager.getConnection("database url");
Source: https://docs.oracle.com/javase/7/docs/api/java/sql/DriverManager.html

I don't know if you can setup a default user, but you can most certainly set up a user with no password.
As for the second question, assuming your connection has adequet rights in MySQL, you can most certainly set the password on any user. The most basic way to do that is to do:
update user set password=password('new_pass') where user = 'someuser';
Optionally you may want to specify the host field as well in the where clause. This needs to be ran in the msql database.

How to connect to a database that requires password without exposing the password?

I am creating an application and I need to connect to a database. The database requires login/password so the application can do operations like select and insert.
In the application I need to connect to the database using login and password, so the application is free to do some tasks on the database. My question is: how do I store and use a password to connect to the database without exposing the password?
I can't simply use a hash or encryption to store the password because the database must recognize the password (I think most or all databases must receive password as plain text).
.
.
Note: The connection is made by the application. No human input to do the connection.
(Edit)More info about the application: it is a web application using servlets/jsp. The database is on the same server of the application. The user for the application is a default user without complete admin powers, but it may insert/delete rows and do most things that involve queries and data modification in tables.

The usual way this is done is to externalize the username/password to a property/config file which is read at runtime (whether or not you use native JDBC/JNDI/CDI/J2EE datasource/etc).
The file is protected via the O/S security by the sysadmins.
The O/S has better tools for protection than app code.

You can use jasypt for the encryption.And store the username and password to datasource.properties file.
public Connection getConnection() throws IOException{
try{
BasicTextEncryptor encryptor = new BasicTextEncryptor();
encryptor.setPassword("jasypt");
Properties props = new EncryptableProperties(encryptor);
props.load( this.getClass().getResourceAsStream("datasource.properties") );
String driver = props.getProperty("datasource.driver");
String url = props.getProperty("datasource.url");
String userName = props.getProperty("datasource.userName");
String password = props.getProperty("datasource.password");
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, userName, password);
conn.setAutoCommit(false);
return conn;
} catch(ClassNotFoundException e) {
e.printStackTrace();
return null;
} catch(SQLException e) {
e.printStackTrace();
return null;
}
}

You should use a config file for this. use spring with JDBC to make your life easier!
http://www.youtube.com/watch?v=f-k823MZ02Q
Checkout the above awesome tutorial on the Spring framework and using JDBC. Watch all of his JDBC and spring tutorials.
BTW, he covers how to store passwords in config files and wire beans etc.. Hope this helps.

If it's a web app, deploy it on a Java EE app server and connect using a JNDI resource. Only the admin who set up the JNDI data resource needs to know about the credentials needed to connect. Users and developers don't even have to know them; just the JNDI lookup name.
It's not possible to completely eliminate the need for someone besides the database owner to know the username and password, but it is possible to restrict that knowledge to the app server owner.
You are also well advised to create separate credentials just for that application and GRANT it the minimum access and permissions needed to accomplish its tasks. There should be no knowledge of system tables or any other resources outside the province of the application. IF DELETE permission isn't necessary, don't grant it. If access should only be read only, that's what you should GRANT to that credential.