PL/SQL block that computes the sum of the salary of all the employees working in the particular department

PL/SQL block

SET SERVEROUTPUT ON
DECLARE
sumSalary number; 
BEGIN
select sum(salary) into sumSalary
from employees
where department_id=&department_id;  
dbms_output.put_line('The sum of salary ->'||sumSalary); 
END;
/

Output:

TCP Socket Programming in Java

Write a server-client TCP socket program where the client takes inputs, sends it to the server to perform a certain operation, and gets back the output of the operation. Run the programs in local host and in different systems in LAN.

/**

*

* @author anuz

*/

public class ClientSide {

/**

* @param args the command line arguments

* @throws java.io.IOException

*/

public static void main(String[] args) throws IOException {

// TODO code application logic here

try (

//name of the computer and the port number to which you want to connect.

Socket socket = new Socket("localhost", 8888);

//readers and writers to write characters over the socket.

PrintWriter out = new PrintWriter(socket.getOutputStream(), true);//to send data to server

BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));//for response from the server

BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));//standard input

) {

System.out.println(in.readLine());

String userInput;

//the loop reads a line at a time from the standard input stream and immediately sends it to the server

while ((userInput = stdIn.readLine()) != null) {

if(userInput.equalsIgnoreCase("exit")){

break;

}

out.println(userInput);

System.out.println(in.readLine());

}

} catch (IOException ex) {

System.out.println(ex.getMessage());

}

}

}

/**

*

* @author anuz

*/

public class ServerSide {

/**

* @param args the command line arguments

* @throws javax.script.ScriptException

*/

public static void main(String[] args) throws ScriptException {

// TODO code application logic here

try {

//server socket port number

ServerSocket serverSocket = new ServerSocket(8888);

while(true){

Socket clientSocket = serverSocket.accept();

System.out.println("connection from :" + clientSocket.getInetAddress()); //display client IP connected to server

PrintStream out = new PrintStream(clientSocket.getOutputStream());

out.println("welcome to the calculator server");

BufferedReader reader = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));

String line;

while ((line = reader.readLine()) != null) {

try {

System.out.println(line);

if (line.equalsIgnoreCase("exit")) {

break;

}

//code for operation of user input.

//------------------------------------------------

ScriptEngineManager mgr = new ScriptEngineManager();

ScriptEngine engine = mgr.getEngineByName("JavaScript");

System.out.println("=>" + engine.eval(line));

out.println("=>" + engine.eval(line));

//-------------------------------------------------

/*

 Security Note:

 You should never use ScriptEngine in a server context with user input. The executed

JavaScript can access all Java classes and thus hijack your application without limit

It executes a script, not evaluates an expression.

*/

}catch (ScriptException ex) {

System.out.println(ex.getMessage());

}

}

}catch (IOException ex) {

System.out.println(ex.getMessage());

}

}

}

}

Output:

Illustration 1: ServerSide

Illustration 2: ClientSide

 

Java Program to calculate factorial by passing object

public class FindFactorial {
int a=0;
  FindFactorial(int i){
    a=i;
  }
  int displayFact(FindFactorial f){
    if(f.a<1)
      return 1;
    else{
         f.a--;
         return (f.a+1)*displayFact(f);
     }
  }
}

 
public class Main {
public static void main(String[] args){
      FindFactorial f1 = new FindFactorial(3);
      System.out.println("factorial ="+ f1.displayFact(f1));
}
}

Output:

Java program with matrix

import java.util.Scanner;

class Sum

{

public static void main(String[] args)

{

int m, n, c, d;

Scanner in = new Scanner(System.in);

System.out.println("Enterin the number of rows and columns of matrix");

m = in.nextInt();

n = in.nextInt();

int first[][] = new int[m][n];

int second[][] = new int[m][n];

int sum[][] = new int[m][n];

System.out.println("Enter the elements of first matrix");

for ( c = 0 ; c < m ; c++ )

for ( d = 0 ; d < n ; d++ )

first[c][d] = in.nextInt();

System.out.println("Enter the elements of second matrix");

for ( c = 0 ; c < m ; c++ )

for ( d = 0 ; d < n ; d++ )

second[c][d] = in.nextInt();

in.close();

for ( c = 0 ; c < m ; c++ )

for ( d = 0 ; d < n ; d++ )

sum[c][d] = first[c][d] + second[c][d]; //replace '+' with '-' to subtract matrices

System.out.println("Sum of entered matrices:-");

for ( c = 0 ; c < m ; c++ )

{

for ( d = 0 ; d < n ; d++ )

System.out.print(sum[c][d]+"\t");

System.out.println();

}

}

}

Output: