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/ch5/postServlet/ControllerHelper.java /ch5/postServlet/ControllerHelper.java

package ch5.postServlet;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.ServletException;

//import the bean from the requiredValidation application
import ch5.requiredValidation.RequestDataRequired;
import javax.servlet.http.HttpServlet;
import shared.HelperBaseCh5;
import shared.ButtonMethod;

public class ControllerHelper extends HelperBaseCh5 {
  
  private RequestDataRequired data =
      new RequestDataRequired();
  
  public ControllerHelper(
            HttpServlet servlet,
            HttpServletRequest request,
            HttpServletResponse response) {
        super(servlet, request, response);
  }
  
  public Object getData() {
    return data;
  }
  
  public void copyFromSession(Object sessionHelper) {
    if (sessionHelper.getClass() == this.getClass()) {
      data = ((ControllerHelper)sessionHelper).data;
    }
  }
  
  protected String jspLocation(String page) {
    return "/WEB-INF/classes/ch5/postServlet/" + page;
  }
  
  @ButtonMethod(buttonName="editButton", isDefault=true)
  public String editMethod() {
    return jspLocation("Edit.jsp");
  }
  
  @ButtonMethod(buttonName="confirmButton")
  public String confirmMethod() {
    //Populate from the query string
    fillBeanFromRequest(data);
    //The next JSP address depends on the validity of the data.
    String address;
    if (isValid(data)) {
      address = jspLocation("Confirm.jsp");
    } else {
      address = jspLocation("Edit.jsp");
    }
    return address;
  }
  
  @ButtonMethod(buttonName="processButton")
  public String processMethod() {
    return jspLocation("Process.jsp");
  }
  
  @Override
  public void doGet()
    throws ServletException, java.io.IOException 
  {
    //Call the method with false to place a new helper in the session
    addHelperToSession("helper", SessionData.IGNORE);
    
    //Edit.jsp is the only page that will be displayed from a GET request.
    String address = editMethod();
    
    request.getRequestDispatcher(address)
        .forward(request, response);
  }
  
  @Override
  public void doPost()
    throws ServletException, java.io.IOException 
  {
    //Check if there is already a helper in the session.
    addHelperToSession("helper", SessionData.READ);
    
    String address = executeButtonMethod();
    
    request.getRequestDispatcher(address)
        .forward(request, response);
  }
  
}

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