j7

/*
Write a java program that implements a multi-thread application that has three threads.
First thread generates random integer number after every one second, if the number is
even; second thread computes the square of that number and prints it. If the number is
odd, the third thread computes the cube of that number and prints it.
*/
package com.mycompany.practical_slip;

import java.util.Random;
import java.util.logging.*;

class NumGenerator implements Runnable {
Random rand = new Random();
int n;

@Override
public void run() {
    while(true) {
        n = rand.nextInt(100);
        System.out.println("Generated number: " + n);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException ex) {
            Logger.getLogger(NumGenerator.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

}

class SqrGenerator implements Runnable {
NumGenerator numGenerator;

SqrGenerator(NumGenerator numGenerator) {
    this.numGenerator = numGenerator;
}

@Override
public void run() {
    while(true) {
        int n = numGenerator.n;
        if(n % 2 == 0)
            System.out.println("Square of " + n + " is " + n*n);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException ex) {
            Logger.getLogger(SqrGenerator.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

}

class CubeGenerator implements Runnable {
NumGenerator numGenerator;
int n;

CubeGenerator(NumGenerator numGenerator) {
    this.numGenerator = numGenerator;
}

@Override
public void run() {
    while(true) {
        int n = numGenerator.n;
        if(n % 2 != 0)
            System.out.println("Cube of " + n + " is " + n*n*n);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException ex) {
            Logger.getLogger(CubeGenerator.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

}

public class slip7_1
{
public static void main(String[] args) {
NumGenerator numGenerator = new NumGenerator();
Thread t1 = new Thread(numGenerator);
t1.start();

    SqrGenerator sqrGenerator = new SqrGenerator(numGenerator);
    Thread t2 = new Thread(sqrGenerator);
    t2.start();
    
    CubeGenerator cubeGenerator = new CubeGenerator(numGenerator);
    Thread t3 = new Thread(cubeGenerator);
    t3.start();
}

}\

/*
2. Write a java program for the following:
i. To create a Product (Pid, Pname, Price) table.
ii. Insert at least five records into the Product table.
iii. Display all the records from a Product table.
Assume Database is already created
*/
package com.mycompany.practical_slip;

import java.sql.*;
import java.util.Scanner;

public class slip7_2
{
public static void main(String[] args) throws SQLException {
Scanner sc = new Scanner(System.in);
Connection conn = DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres", "postgres", "postgres");

    int ch;
    do {
        System.out.println("Menu");
        System.out.println("1. Create table Product.");
        System.out.println("2. Insert into Product.");
        System.out.println("3. Display records of product.");
        System.out.println("4. Exit.");
        
        System.out.println("------------------------------");
        System.out.println("Enter your choice:");
        ch = sc.nextInt();
        
        switch(ch) {
            case 1: create(conn);
                break;
            case 2: insert(conn);
                break;
            case 3 : select(conn);
                break;
            default : System.out.println("Invalid choice.");
                break;
        }
    } while(ch != 4);
}

private static void create(Connection conn) throws SQLException {
    String sql = "create table if not exists product("
                    + "pid int primary key,"
                    + "pname varchar(30),"
                    + "price decimal(10, 2))";
    Statement stmt = conn.createStatement();
    stmt.execute(sql);
}

private static void insert(Connection conn) throws SQLException {
    String sql = "insert into product values(?, ?, ?)";
    
    PreparedStatement pt = conn.prepareStatement(sql);
    Scanner sc = new Scanner(System.in);
    
    System.out.println("Enter pid:");
    int pid = sc.nextInt();
    sc.nextLine();
    
    System.out.println("Enter pname:");
    String name = sc.nextLine();
    
    System.out.println("Enter price");
    float price = sc.nextFloat();
    
    pt.setInt(1, pid);
    pt.setString(2, name);
    pt.setFloat(3, price);
    pt.executeUpdate();
}

private static void select(Connection conn) throws SQLException {
    String sql = "select * from product";
    Statement stmt = conn.createStatement();
    stmt.executeQuery(sql);
    ResultSet res = stmt.getResultSet();
    
    while(res.next()) {
        System.out.println("Pid = " + res.getInt("pid"));
        System.out.println("PName = " + res.getString("pname"));
        System.out.println("Price = " + res.getFloat("price"));
        System.out.println("----------------------------------------------");
    }
}

}