Thực hành EJB (Enterprise Java Bean) Lab 11
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (533.67 KB, 7 trang )
Enterprise Application Development in Java EE
Lab 11
Query and Criteria API
Mục tiêu
- Sử dụng Criteria Query API để viết các truy vấn
Phần I Bài tập step by step
Bài 7.1
Xây dựng truy vấn tìm danh sách customer theo Customer Name trong ứng dụng EJB xây
dựng ở bài 6.1 và 6.2
Step 1: Khai báo phương thức searchCustomer ở CRMApplication-ejb
CustomerBeanLocal.java
CustomerBeanLocal.java
package beanpack;
import entity.Address;
import entity.Customer;
import java.util.List;
import javax.ejb.Local;
/**
*
* @author Quang
*/
@Local
public interface CustomerBeanLocal {
public void createCustomer(Customer customer, List<Address> listAddress);
public List<Customer> searchCustomer(String custName);
}
IT Research Department
@BKAP 2015
Page 1 / 7
Enterprise Application Development in Java EE
Step 2: Thực thi phương thức searchCustomer ở CustomerBean.java. Sử dụng Criteria
query để truy vấn các customer theo Customer Name
CustomerBean.java
package beanpack;
import entity.Address;
import entity.Customer;
import entity.Customer_;
import java.util.List;
import javax.ejb.Stateless;
import javax.ejb.TransactionManagement;
import javax.ejb.TransactionManagementType;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.TypedQuery;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.ParameterExpression;
import javax.persistence.criteria.Root;
/**
*
* @author Quang
*/
@Stateless
@TransactionManagement(TransactionManagementType.CONTAINER)
public class CustomerBean implements CustomerBeanLocal {
//Persistence
@PersistenceContext(unitName = "CRMApplication-ejbPU")
EntityManager em;
@Override
public void createCustomer(Customer customer, List<Address> listAddress) {
customer.setListAddress(listAddress);
for (Address addr : listAddress) {
addr.setCustomer(customer);
}
em.persist(customer);
}
@Override
public List<Customer> searchCustomer(String custName) {
List<Customer> listCus = null;
CriteriaBuilder cb = em.getCriteriaBuilder();
//Tao doi tuong CriteriaQuery tu cb
CriteriaQuery<Customer> cq = cb.createQuery(Customer.class);
//Tao root interface tu criteria query
Root<Customer> cust = cq.from(Customer.class);
// Tao ParameterExpression
ParameterExpression<String> p = cb.parameter(String.class);
//dieu kien truy van
cq.select(cust).where(cb.like(cust.get(Customer_.customerName), "%" + custName + "%"));
IT Research Department
@BKAP 2015
Page 2 / 7
Enterprise Application Development in Java EE
//Tao loai truy van
TypedQuery<Customer> query = em.createQuery(cq);
//Nhan ket qua
listCus = query.getResultList();
return listCus;
}
}
Step 3: Tạo form nhập thông tin Customer Name để search
CRMApplication-war Web Pages New Other Web JSP
CustomerSearch.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Customer Search Page</title>
</head>
<body>
<form name="CustSearchForm" method="POST" action="CustomerSearch">
<table colspan="2">
<tr>
<td>Customer Name: </td>
<td><input type="text" size="20" name="customerName"/></td>
</tr>
<tr>
<td colspan="2" align="center"><input type="submit" value="Search"/></td>
</tr>
</table>
</form>
</body>
</html>
Step 4: Tạo Servlet CustomerSearchServlet thực hiện việc search Customer theo Customer
Name
CRMApplication-war Source Packages Servlet New Other Web Servlet
IT Research Department
@BKAP 2015
Page 3 / 7
Enterprise Application Development in Java EE
CustomerSearchServlet.java
package servlet;
import beanpack.CustomerBeanLocal;
IT Research Department
@BKAP 2015
Page 4 / 7
Enterprise Application Development in Java EE
import entity.Address;
import entity.Customer;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import javax.ejb.EJB;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
*
* @author Quang
*/
public class CustomerSearch extends HttpServlet {
//Goi Enterprise Bean
@EJB
private CustomerBeanLocal customerBean;
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
//Nhan thong tin Customer Name nhap vao de search
String custName = request.getParameter("customerName");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet CustomerSearch</title>");
out.println("</head>");
out.println("<body>");
//Goi phuong thuc searchCustomer
List<Customer> listCus = customerBean.searchCustomer(custName);
//Hien thi danh sach Customer tim duoc
out.println("<table border='1'><tr><th>Customer Name</th><th>Address</th></tr>");
for (Customer cust : listCus) {
out.println("<tr><td>"+cust.getCustomerName()+"</td><td>");
for (Address addr : cust.getListAddress()) {
out.println("Address Type - "+addr.getAddressType());
out.println("| Address Line - "+addr.getAddressLine() +"
");
}
out.println("</td></tr>");
}
out.println("</table>");
IT Research Department
@BKAP 2015
Page 5 / 7
Enterprise Application Development in Java EE
out.println("</body>");
out.println("</html>");
}
}
//
/**
* Handles the HTTP <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
Ứng dụng sau khi hoàn thành
IT Research Department
@BKAP 2015
Page 6 / 7
Enterprise Application Development in Java EE
Step 5: Build and Run Application
IT Research Department
@BKAP 2015
Page 7 / 7
