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Connecting different user to 1 server(database derby) in netbeans using java

I made an inventory system in netbeans using the language java and i connect it to derby as my database it is already working as a whole system but I want to have a client-server functionality what I mean is I want my program to have a server which holds the database(different computer) and different users with different computers which they can save/view data at the same time to the database means they are connected in one network.
Working with multiple connections to a single database.
What code can I use or method or do I have to import something?
I did some research and the only thing that I found is socket which can be used to create a chat between server and a client.
But I only tried the IP 127.0.0.1 for the client since I am making running the server and the client in the same computer.
And also can I open the connection of the server in the client form and send data like SQLQuery so I can save it in the database of the server?
Where can I see examples for these? Please help thanks

Yes, Derby supports a client-server configuration of your application.
Deploying your application in the client-server configuration is straightforward:
Deploy the Derby Network Server, for example by running the startNetworkServer script that is included with the Derby distribution.
Ensure that derbyclient.jar is in your application's CLASSPATH, and that you register "org.apache.derby.jdbc.ClientDriver" with the JDBC DriverManager.
Change your JDBC Connection URL from jdbc:derby:<db details> to jdbc:derby://<host:port>/<db details>.
If this is your first time using Derby, I strongly recommend working your way through the Derby tutorial at https://db.apache.org/derby/docs/10.12/getstart/index.html
For more information about running the Derby Network Server to service database requests for your applications, read the Derby Admin Guide: https://db.apache.org/derby/docs/10.12/adminguide/index.html

Use the IP 0.0.0.0 or for all connections in the server. The the connection url should include the name of the server or the ip address of the server in the network. When you use ip 127.0.0.1 or localhost derby can only accept connections to the database in the same machine, in this case localhost. All of this can be done by your network application server

JDBC Remote MySQL Connectivity

I'm developing a Java Swing based app which uses JDBC to connect to a MySQL database. As such, the software directly remotely access the database from whichever computer it happens to be running on. Additionally, the app uses prepared statements to query the database and the database is hosted on a shared CPanel hosting account (if that matters).
The snippet of code I use to connect to the database is as follows (fairly standard connect code I think and all strings in all caps contain the correct contents):
String url = "jdbc:mysql://URL:PORT/DB_NAME?connectTimeout=3000";
Connection conn = DriverManager.getConnection(url, USERNAME, PASSWORD);
I have only ever successfully used the app from one IP. Before I use the app from an IP, I have to manually whitelist the IP by adding it as an allowed remote MySQL access host. If I don't add the IP as an allowed access host, the server refuses my connection and I get the resultant error:
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.
Then if I whitelist an IP and try to connect from it, I don't get that error and the app connects to the database properly.
This system would be okay if the app were only going to be used from one IP, but it needs to work from any IP since I cannot predict who will download and use it. The only solution I see would be to do a global whitelist of all IPs in the allowed MySQL access hosts area. However, that seems like it has many drawbacks, such as being insecure as anyone who has the correct password could log in (and would thus be susceptible to brute force attacks). This seems to corroborate the hypothesis that that method is insecure. Thus, I would like to have a system of communicating between the app and database that is IP-independent (doesn't require whitelisting all the IPs).
Additionally (I don't know if this makes sense or matters), but I believe some of the areas I expect the app to be used in block certain protocols. Thus, (I think) I would like it if the selected method of communication only used HTTP or some other widely-used protocol.
I did some research into this problem and my efforts led me to 2-tier and n-tier models of database communication. Perhaps I could do something like make a PHP page which accepts a statement and a series of parameters (plus a password to gain entry), executes the statement, and then returns the result back as JSON. However, this seems like another less-than-ideal method as it seems like it would also have security problems.
I'm sure someone more experienced and knowledgeable than I has already come across this problem and developed a solution.
Therefore, my question: What is the preferred method of connecting to a MySQL database from a Java app in an IP-independent way?
I greatly appreciate and thank you for your time.

You're on the right track:
1) If you want any arbitrary client to connect directly to your database, and the clients can have any arbitrary IP address ... then you're probably going to have to effectly disable IP security be whitelisting all possible client IP addresses.
2) On the other hand, if you only allow local access to mySql (by far the most common scenario), then you can create a web app to interface between your clients and mySql.
SUGGESTION:
Consider creating a "REST" web service that your clients can talk to.
Here's a good tutorial that might help you get started:
REST with Java (JAX-RS) using Jersey - Tutorial
Q: Does your Swing app really need to emit "raw SQL"? Or can it make "high level" queries? REST is ideally suited for the latter.
PS:
Here's another, short example that might help suggest some design alternatives with REST, mySQL and Java for you:
http://www.9lessons.info/2012/09/restful-web-services-api-using-java-and.html

You are up against the policies -- primarily the security policies -- of your hosting provider. It's generally considered insecure to allow port 3306 (MySQL) connections from the whole internet. It certainly lays your MySQL server open to trivial denial-of-service attacks. (It just takes some knucklehead controlling a botnet to send in lots of port 3306 connection attempts. They don't even have to be successful connection attempts.) If you're sharing your MySQL server with other customers of your hosting provider, they have every incentive to restrict your remote access to their server.
Most folks who build database applications for deployment on the public internet do it by providing web services to hit the database with the specific operations required by the application. The application deployed at the end-user's machine then uses HTTP (or HTTPS for security) to access those web services. In turn the web services access the database. That's what multitier operations do. You're right that there are security problems, but you can mitigate them with careful development of your web service code.
You could use SSH tunneling to handle your database access. The SSH suite of remote-access applications allows port forwarding. To use this, you would establish (authenticated and encrypted) ssh connections between your end-users' machines and your database machine, that forward port 3306. Then your users could connect to localhost:3306, and that net traffic would be forwarded to your database server. It's pretty flexible and quite secure, if not completely simple to configure.
You might also investigate using SQL Relay. It's generally used for connection pooling and management within a data center network, but it might work for this purpose.
Be careful opening up your MySQL server to the world! If you do that you may want to require the use of TLS encrypted conections.

Can you create a connection between a Java Application to an Access database and while uploading the database to my website

I have written a few Java Applications offline before connecting to an Access Database but if I upload the database to a website and change the connection from e:// (filepath) to the file path of a webpage, would this work?
What would be the easiest way to connect to an online database?
This application would need to include:
Name
Password
Then Teams involved with each person registered

Maybe this could help you:
The Easysoft JDBC-ODBC Bridge provides JDBC access from Java applets,
applications or application servers to ODBC databases such as
Microsoft SQL Server, Microsoft Access and so on.
Being a Type 3 client/server solution allows the Java applications and
ODBC drivers to be on separate machines.
The client driver is 100% Java, eliminating the hassle of client side
ODBC drivers. It is compatible with any third party ODBC driver and
gives concurrent access to multiple data sources from multiple client
devices.
Importantly, it is built for commercial use with high transaction
rates and dependable performance.
http://www.easysoft.com/products/data_access/jdbc_odbc_bridge/index.html?gclid=COexrKf8h70CFagKwwod3UUAdA

Connecting Access Databases remotely?

Currently I have a Java application which performs all I wanted and the limitation
in it is "It only resides on the Local machine for which it needs to work". I have the Access Databases located on a Remote Server and I install the Java app on the remote server to connect the databases using a connection string jdbc:odbc:DRIVER={Microsoft Access Driver (*.mdb)}; DBQ=D:\\DATA\\DPPI\\DATA\\DPPI\\DPPIPR01.mdb;
It connects to Access Databases and do all the business logic with them.
Enhancements (to be done):
Making the application online - not a big issue.
Connecting the databases remotely - its the only concern.
If I make the Application Online the Access Databases need to be connecting through network (somewhat like IP or some web address).
Problem:
But after going through this Connect to Access database remotely It seems my requirement can not be completed.
Is there any way if I'm able to upload the database to the online web hosting server and access the database from there only? If yes, then how should I do the connectivity since Access Database connects by giving the fully qualified name containing drive letter and all.
But how should I proceed further so that I may be able to connect the mdb Databases remotely?
ADO Solution:
But after going through the link: http://webcheatsheet.com/ASP/access_connection_strings.php, it seems we can perform remote Access Database connectivity.
The solution for the ADO is something like:
connectionString="Provider=MS Remote; Remote Server=http://your_remote_server_ip;" &_
"Remote Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\your_database_name.mdb"
I'm a tad confused to how Access Database we can connect.
There is one more question in my head.
I'm making use of Type-1 Driver. Should the Type-4 Driver support the remote connectivity?

If your application is a server side application (like a web application) and your server's OS is Windows then theoretically it is possible to use your Access database. In this scenario, the Access database is local to your application. In your connection string you can simply use the path to the Access database inside your server's file system.
But keep in mind, that Access is a desktop database not made to use it as a server database. This can lead to poor performance and maybe system crashes. And it is possible that there are some licencing issues for this use case.
So even it may be possible to use Access with a server application it is strongly recommended to use a real server database like MySQL, MS SQL Server, etc. Even an embedded database like Apache Derby or H2 would be a better fit.
If your application runs at client side like a fat client, then your only chance to use Access is to put it on a network filesystem, so it is visible from every client. But this works only inside a LAN. If you cannot put it on a network filesystem then you have to use a real server database.

Do not use Provider=MS Remote (RDS) for new development. Here is a quote from the MSDN article
Microsoft OLE DB Remoting Provider (ADO Service Provider)
Important
Beginning with Windows 8 and Windows Server 2012, RDS server components are no longer included in the Windows operating system (see Windows 8 and Windows Server 2012 Compatibility Cookbook for more detail). RDS client components will be removed in a future version of Windows. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. Applications that use RDS should migrate to WCF Data Service.
As others have suggested, you should seriously consider using a different back-end database for this particular application.

What if I'm able to call another java application residing on the Server housing the Microsoft Access Databases? Can you please let me know if it can be the solution such that I will have the division of my application into two:
1. The Online java Application performing 2 things: Accepting the requests coming in and waiting for the response to come from another application running on the Server housing the Microsoft Access Databases.
2. The Java application installed on the Server housing the Microsoft Access Databases only responsible for connecting and returning the DTO (Data Transfer Objects) -or some kind of objects in Collections.
So, I would expect a serverside program to handle the communication with the DB and the client application would communicate with the server app.
Please let me know if I should proceed in this manner.

it can be done by marking the traffic and queueing the traffic from the server---to----remote site ---(QOS..quality of service ) .....the two sites will be connected through VPN methods to reduce the unnecessary hops that will improve the latency plus add the security , thus server and remote site will logically act as if they are on the same network (LAN)
regards ,
Ali Rehan

how to share a database to different pc's for a java desktop application?

I am making an application which have to be used in different pc's, and it has to share the same database. I have no idea how to do it. I am using the java as programming language and mysql as database. Please help me to do this task...

Use JDBC and connect all your app to one MySql DB Server

The way to talk to a database in Java is JDBC.
See http://download.oracle.com/javase/tutorial/jdbc/index.html for a good tutorial on how to use it.

On server-side you should create user which will be granted privileges to access your database from different foreign hosts:
GRANT ALL ON *.* TO 'someuser'#'somehost';
Read more here: http://dev.mysql.com/doc/refman/4.1/en/grant.html
On client-side you should configure database connection to use host where your database is installed. Read JDBC API reference for details.

Does a client-server model not work for you? If you have somewhere to host a server the normal method accomplishing something like this is to encapsulate your database behind the server and all clients connect to your server to exchange information.
You have a variety of options for communicating between the clients and the server:
Your server could be a simple web app where your clients all make URL calls to the server to accomplish various tasks. Implementing REST or SOAP would make the calls even easier if you're doing anything non-trivial.
RMI if your not going over the internet makes things really easy (you can get the basics of RMI in a few hours of reading).
Assuming you have the network connectivity, you can also just have each client make their own connection directly to the database. But only do this if you are on a safe intranet only.