Repository
https://github.com/dmlloyd/openjdk
What Will I Learn?
- You will learn how to create connection with socket programming
- You will learn connect two program in one package
- You will learn how to create method like chatting Apps
Requirements
- you must know basic of java programming
- you must know about socket programming
- you must know how to set port on two program
Difficulty
- Intermediate
Tutorial Contents
okay, on this occasion I will create a tutorial on how to create a connection using socket programming, socket programming is very widely used in large applications such as chat application or application sender file . and this time I will make the method.
- the first step you should do is create a new package in NetBeans.
then name it for the package you have created
***
- then type the program below, I will explain it.
```
package socketprogramming;
import java.io.*;
import java.net.*;
public class server{
ServerSocket providerSocket;
Socket connection = null;
ObjectOutputStream out;
ObjectInputStream in;
String message;
server(){}
void run()
{
try{
providerSocket = new ServerSocket(2004, 10);
System.out.println("Waiting for connection");
connection = providerSocket.accept();
System.out.println("Connection with IP " + connection.getInetAddress().getHostName());
out = new ObjectOutputStream(connection.getOutputStream());
out.flush();
in = new ObjectInputStream(connection.getInputStream());
sendMessage("Program is successful Connected");
do{
try{
message = (String)in.readObject();
System.out.println("client>" + message);
if (message.equals("hi....!"))
sendMessage("Hi... to");
}
catch(ClassNotFoundException classnot){
System.err.println("Data received ");
}
}while(!message.equals("bye"));
}
catch(IOException ioException){
}
finally{
try{
in.close();
out.close();
providerSocket.close();
}
catch(IOException ioException){
}
}
}
void sendMessage(String msg)
{
try{
out.writeObject(msg);
out.flush();
System.out.println("server>" + msg);
}
catch(IOException ioException){
}
}
public static void main(String args[])
{
server server = new server();
while(true){
server.run();
}
}
}
```
- okay, I'll explain the important parts of the above program:
- ```package socketprogramming;``` this is the declaration of the package name, make sure you create both programs in the same package.
- ```import java.io. *;``` this is a class that works for input and output process.
- below is the process of creating object socket programming that we will call in the program.
```
ServerSocket providerSocket;
Socket connection = null;
```
- this is the declaration of the input object, output, and to display the message.
```
ObjectOutputStream out;
ObjectInputStream in;
String message;
```
- ```server ()``` This is a class declaration server.
- this is the process of calling the object we have created before.
```
providerSocket = new ServerSocket(2004, 10);
System.out.println("Waiting for connection");
```
- ```connection = providerSocket.accept();```this is the process of receiving connections.
- This works to show that the system has been successfully connected with the IP address that has been determined.
```
System.out.println("Connection with IP " + connection.getInetAddress().getHostName());
```
- below serves to display the input, output and connection
```
out = new ObjectOutputStream(connection.getOutputStream());
out.flush();
in = new ObjectInputStream(connection.getInputStream());
sendMessage("Program is successful Connected");
```
- this is the conditioning of the situation that occurs when the program is run.
```
do{
try{
message = (String)in.readObject();
System.out.println("client>" + message);
if (message.equals("hi....!"))
sendMessage("Hi... to"); }
catch(ClassNotFoundException classnot){
System.err.println("Data received ");
}}while(!message.equals("bye"));
}catch(IOException ioException){
}
```
- this is to close the programming socket.
```
in.close();
out.close();
providerSocket.close();
```
- okay, I think it's enough explanation for the *server* program, then we will create a class *client*
***
- type the program below for the class client
```
package socketprogramming;
import java.io.*;
import java.net.*;
public class client{
Socket requestSocket;
ObjectOutputStream out;
ObjectInputStream in;
String message;
client(){}
void run()
{
try{requestSocket = new Socket("localhost", 1718);
System.out.println("Connected to localhost in port 1718");
out = new ObjectOutputStream(requestSocket.getOutputStream());
out.flush();
in = new ObjectInputStream(requestSocket.getInputStream());
do{
try{
message = (String)in.readObject();
System.out.println("server>" + message);
sendMessage("Hi my server");
message = "bye";
sendMessage(message);
}
catch(ClassNotFoundException classNot){
System.err.println("data received in unknown format");
}
}while(!message.equals("bye"));
}
catch(UnknownHostException unknownHost){
System.err.println("You are trying to connect to an unknown host!");
}
catch(IOException ioException){ }
finally{
try{in.close();
out.close();
requestSocket.close();
}
catch(IOException ioException){
}}}
void sendMessage(String msg)
{try{
out.writeObject(msg);
out.flush();
System.out.println("client>" + msg);}
catch(IOException ioException){
}}public static void main(String args[])
{ client client = new client();
client.run();
}}
```
- I do not think much need to explain again to the second program because basically almost the same, but only different in some part only.
***
- ```Socket requestSocket;``` this is for connection request
- ```try {requestSocket = new Socket (" localhost ", 1718);``` and this is for connection creation
- ```System.out.println (" Connected to localhost in port 1718 ");``` This is for notification that the program is successfully connected.
- okay, both programs we have created, then we will try to run the program if it will successfully connected.
- we just to right click on the server program and select run file.
***
- if the program successfully connected then it will look like this.
- Okay, the program is done, thank you for following my tutorial to complete.
Curriculum
- Java Tutorial : How To Create java JFrame/GUI To Play Music On NetBeans
- Java Tutorial: How To Select And Send All File In One Folder Using "for" Looping Method On NetBeans
- HOW TO CREATE ACTION TO AUTO SELECT FILE USING "if" CONDITIONAL ON JAVA
- Java Tutorial: How To Create GUI For Send And Receive File Application On NetBeans
- Java Tutorial: How To Create a Program To Send And Receive Files On NetBeans
Proof of Work Done
https://gist.github.com/andilapulga/35c1d91d6964f05f58654076f93ccd40