Pagination in Spring Hibernate Mvc application

Points To Remember



Pagination in Spring Hibernate Application using Bootstrap


  • Create a Domain Person.
  • Create a Service PersonService
  • Create a Dao PersonDao.
  • Create a Controller PersonController.
  • Create a Taglib PaginationTaglib.

Person.java
package com.ekiras.domain;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="person")
public class Person {

 public Person(){};
 public Person(String name,Integer age){
  this.name = name;
  this.age  = age;
 }
 
 
 @Id
 @GeneratedValue(strategy=GenerationType.AUTO)
 @Column(name="id")
 private Long id;
 
 @Column(name="name")
 private String name;
 
 @Column(name="age")
 private Integer age;

       // GETTERS and SETTERS

PersonService.java
package com.ekiras.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.ekiras.dao.PersonDAO;
import com.ekiras.domain.Person;

@Service
public class PersonService {

 @Autowired
 private PersonDAO personDAO;
 
 
 public List<Person> list(Integer offset, Integer maxResults){
  return personDAO.list(offset, maxResults);
 }
 
 public Long count(){
  return personDAO.count();
 }
 
 public void save(){
  personDAO.save();
 }
 
}

PersonDAO.java
package com.ekiras.dao;

import java.util.List;

import org.hibernate.SessionFactory;
import org.hibernate.criterion.Projections;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import com.ekiras.domain.Person;

@Repository
@Transactional
public class PersonDAO {

 @Autowired 
 private SessionFactory sessionFactory;
 
 @SuppressWarnings("unchecked")
 @Transactional
 public List<Person> list(Integer offset, Integer maxResults){
  return sessionFactory.openSession()
    .createCriteria(Person.class)
    .setFirstResult(offset!=null?offset:0)
    .setMaxResults(maxResults!=null?maxResults:10)
    .list();
 }
 
 
 public Long count(){
  return (Long)sessionFactory.openSession()
    .createCriteria(Person.class)
    .setProjection(Projections.rowCount())
    .uniqueResult();
 }
 
 
 public void save(){
  for(int itr=1;itr <= 100 ; itr++){
   Person person = new Person("Person_"+itr,Math.max(25, (itr%2)*35));
   sessionFactory.openSession()
   .save(person);
  }
  
  
  
 }
 
}

PersonController.java
package com.ekiras.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

import com.ekiras.service.PersonService;

@Controller
@RequestMapping(value="/person")
public class PersonController {

 @Autowired
 private PersonService personService;
 
 @RequestMapping(value="/list")
 public String list(Model model, Integer offset, Integer maxResults){
  model.addAttribute("persons", personService.list(offset, maxResults));
  model.addAttribute("count", personService.count());
  model.addAttribute("offset", offset);
  return "/person/list";
 }
 
 @RequestMapping(value="/save")
 public String save(){
  personService.save();
  return "/person/list";
 }
 
}

PaginationTaglib.java
package com.ekiras.taglib;

import java.io.Writer;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.SimpleTagSupport;

public class PaginationTaglib extends SimpleTagSupport {
 private String uri;
 private int offset;
 private int count;
 private int max = 10;
 private int steps = 10;
 private String previous = "Previous";
 private String next = "Next";

 private Writer getWriter() {
  JspWriter out = getJspContext().getOut();
  return out;
 }

 @Override
 public void doTag() throws JspException {
  Writer out = getWriter();

  try {
   out.write("<nav>");
   out.write("<ul class=\"pagination\">");
   
   if(offset<steps)
    out.write(constructLink(1, previous, "disabled", true));
   else
    out.write(constructLink(offset-steps, previous, null, false));
   
   for(int itr=0;itr<count;itr+=steps) {
    if(offset==itr)
     out.write(constructLink((itr/10+1)-1 *steps, String.valueOf(itr/10+1), "active", true));
    else
     out.write(constructLink(itr/10*steps, String.valueOf(itr/10+1), null , false));
   }

   if(offset+steps>=count)
    out.write(constructLink(offset+steps, next, "disabled", true));
   else
    out.write(constructLink(offset+steps, next, null , false));
   
   
   out.write("</ul>");
   out.write("</nav>");
  } catch (java.io.IOException ex) {
   throw new JspException("Error in Paginator tag", ex);
  }
 }


 private String constructLink(int page, String text, String className, boolean disabled) {
  StringBuilder link = new StringBuilder("<li");
  if (className != null) {
   link.append(" class=\"");
   link.append(className);
   link.append("\"");
  }
  if(disabled)
   link.append(">").append("<a href=\"#\">"+text+"</a></li>");
  else
   link.append(">").append("<a href=\""+uri+"?offset="+page + "\">"+text+"</a></li>");
  return link.toString();
 }

 public String getUri() {
  return uri;
 }

 public void setUri(String uri) {
  this.uri = uri;
 }

 public int getOffset() {
  return offset;
 }

 public void setOffset(int offset) {
  this.offset = offset;
 }

 public int getCount() {
  return count;
 }

 public void setCount(int count) {
  this.count = count;
 }

 public int getMax() {
  return max;
 }

 public void setMax(int max) {
  this.max = max;
 }

 public String getPrevious() {
  return previous;
 }

 public void setPrevious(String previous) {
  this.previous = previous;
 }

 public String getNext() {
  return next;
 }

 public void setNext(String next) {
  this.next = next;
 }

 public int getSteps() {
  return steps;
 }

 public void setSteps(int steps) {
  this.steps = steps;
 }

}

list.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
 pageEncoding="UTF-8"%>
<%@ taglib prefix="tag" uri="/WEB-INF/taglibs/customTaglib.tld"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link rel="stylesheet" type="text/css" href="/css/bootstrap.css" />
<link rel="stylesheet" type="text/css" href="/css/bootstrap.min.css" />
<link rel="stylesheet" type="text/css" href="/css/font-awesome.min.css" />
<title>| Ekiras</title>
</head>
<body>
 <nav class="navbar navbar-default">
 <div class="container-fluid">
  <!-- Brand and toggle get grouped for better mobile display -->
  <div class="navbar-header">
   <button type="button" class="navbar-toggle collapsed"
    data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
    <span class="sr-only">Toggle navigation</span> <span
     class="icon-bar"></span> <span class="icon-bar"></span> <span
     class="icon-bar"></span>
   </button>
   <a class="navbar-brand" href="#">Brand</a>
  </div>

  <!-- Collect the nav links, forms, and other content for toggling -->
  <div class="collapse navbar-collapse"
   id="bs-example-navbar-collapse-1">
   <ul class="nav navbar-nav">
    <li class="active"><a href="#">Link <span class="sr-only">(current)</span></a></li>
    <li><a href="#">Link</a></li>
    <li class="dropdown"><a href="#" class="dropdown-toggle"
     data-toggle="dropdown" role="button" aria-expanded="false">Dropdown
      <span class="caret"></span>
    </a>
     <ul class="dropdown-menu" role="menu">
      <li><a href="#">Action</a></li>
      <li><a href="#">Another action</a></li>
      <li><a href="#">Something else here</a></li>
      <li class="divider"></li>
      <li><a href="#">Separated link</a></li>
      <li class="divider"></li>
      <li><a href="#">One more separated link</a></li>
     </ul></li>
   </ul>
   <form class="navbar-form navbar-left" role="search">
    <div class="form-group">
     <input type="text" class="form-control" placeholder="Search">
    </div>
    <button type="submit" class="btn btn-default">Submit</button>
   </form>
   <ul class="nav navbar-nav navbar-right">
    <li><a href="#">Link</a></li>
    <li class="dropdown"><a href="#" class="dropdown-toggle"
     data-toggle="dropdown" role="button" aria-expanded="false">Dropdown
      <span class="caret"></span>
    </a>
     <ul class="dropdown-menu" role="menu">
      <li><a href="#">Action</a></li>
      <li><a href="#">Another action</a></li>
      <li><a href="#">Something else here</a></li>
      <li class="divider"></li>
      <li><a href="#">Separated link</a></li>
     </ul></li>
   </ul>
  </div>
  <!-- /.navbar-collapse -->
 </div>
 <!-- /.container-fluid --> </nav>

 <div class="container">
  <div class="well">
   <strong>List of Persons</strong>
  </div>
  <table class="table table-stripped">
   <tr>
    <th>S.No</th>
    <th>Name</th>
    <th>Age</th>
   </tr>
   <c:forEach items="${persons}" var="person" varStatus="itr">
    <tr>
     <td>${offset + itr.index +1 }</td>
     <td>${person.name }</td>
     <td>${person.age }</td>
    </tr>
   </c:forEach>
  </table>
  <tag:paginate max="15" offset="${offset}" count="${count}"
   uri="/person/list" next="&raquo;" previous="&laquo;" />
 </div>


 <script type="text/javascript" src="/js/jquery.js"></script>
 <script type="text/javascript" src="/js/bootstrap.min.js"></script>
</body>
</html>

This is how you can do pagination using bootstrap style in spring hibernate mvc application.


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