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What is Java bean class,POJO Class in Java


Bean is the normal class of java which contains a set of properties to read and write data in object pattern.  It will work as an intermediate between the form component and servlet.
request.getParameter() is directly get the data from form component which is not secure and fast in data communication hence all form data will be inserted into java bean class and save into the database.it provides better security and optimization as compare to form-based data communication.
Java bean class convert text data to object pattern.
class Classname implements Serializable
{
       data member;
       properties;
}
bean class is also used to 3-tier (layer) architecture in java to implement the project , it is also called MVC architecture where M means Model, V means View, the C means Controller.
The view is used to contain the design layer using HTML+CSS+JS+JQUERY
The controller is used to design code using Servlet.
Model is used to communicate data from database to application, bean class will work as a  model object.
Code of Design Layer:-
<section>
    <h1>Welcome in home page</h1>
     <hr>
    <center>
             <a href="login.jsp"> <h1>Login HERE</h1></a>
        <hr>
         <h1>NEW EMPLOYEE REGISTER HERE</h1>
    <form action="EmpSer" method="post">
        <input type="text" name="txtempid" placeholder="Enter employee id" />
        <br>
        <br>
        <input type="text" name="txtemppass" placeholder="Enter employee password" />
        <br>
        <br>
        <input type="text" name="txtempname" placeholder="Enter employee name" />
        <br>
        <br>
        <input type="text" name="txtempjob" placeholder="Enter employee job" />
        <br>
        <br>
        <input type="text" name="txtempsalary" placeholder="Enter employee salary" />
        <br>
        <br>
        <input type="submit" name="btnsubmit" value="Register" />
    </form>
    <% if (request.getParameter("q")!=null) out.print(request.getParameter("q"));  %>
    </center>
</section>
Step2nd:-
Create Bean class
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package bean;
import java.io.Serializable;
/**
 *
 * @author Hp
 */
public class Register implements Serializable{
    private int empid;
    private String empname;
    private String emppass;
    private String job;
    private int empsalary;

    public int getEmpid() {
        return empid;
    }

    public void setEmpid(int empid) {
        this.empid = empid;
    }

    public String getEmpname() {
        return empname;
    }

    public void setEmpname(String empname) {
        this.empname = empname;
    }

    public String getEmppass() {
        return emppass;
    }
    public void setEmppass(String emppass) {
        this.emppass = emppass;
    }
    public String getJob() {
        return job;
    }
    public void setJob(String job) {
        this.job = job;
    }
    public int getEmpsalary() {
        return empsalary;
    }
    public void setEmpsalary(int empsalary) {
        this.empsalary = empsalary;
    }
 }
Step3rd:-
Create Servlet and Class Bean class Object:-
public class EmpSer extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try  {
          Class.forName("com.mysql.jdbc.Driver");
          Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/javatest","root","");
          Statement st = con.createStatement();
          Register obj = new Register();
          obj.setEmpid(Integer.parseInt(request.getParameter("txtempid")));
          obj.setEmpname(request.getParameter("txtempname"));
          obj.setEmppass(request.getParameter("txtemppass"));
          obj.setJob(request.getParameter("txtempjob"));
          obj.setEmpsalary(Integer.parseInt(request.getParameter("txtempsalary")));
          int x = st.executeUpdate("insert into emp (empid,password,empname,job,salary) values('"+obj.getEmpid()+"','"+obj.getEmppass()+"','"+obj.getEmpname()+"','"+obj.getJob()+"','"+obj.getEmpsalary()+"')");
          if(x!=0)
              //response.sendRedirect("home.jsp");
              response.sendRedirect("home.jsp?q=data inserted successfully");
                         }
        catch(Exception ex)
        {
            out.write(ex.getMessage().toString());
        }
    }
}

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