Sunday, September 16, 2018

How to use Spring boot/MySQL with Thymeleaf

At first, add these dependencies in pom.xml.
<!-- JPA Data -->
<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<!-- Use MySQL Connector-J -->
<dependency>
   <groupId>mysql</groupId>
   <artifactId>mysql-connector-java</artifactId>
</dependency>
Then add these settings in application.properties.
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
#Change "test" at the end to your database name.
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
#Change "yourpassword" to your password of mysql's root user.
spring.datasource.password=yourpassword
#Supposing you are using MySQL5
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
If you don't have a database yet, start your mysql and run this command to create a database.
Create database test;
use test;
Create a table too.
Drop table if exists cat;
Create table cat( 
   id int not null auto_increment, 
   name varchar(100) not null, 
   rescued date not null, 
   vaccinated tinyint(1) not null, 
   primary key (id) 
);
Then insert records.
insert into cat(name, rescued, vaccinated)values('nyan','2018-10-01','1');
insert into cat(name, rescued, vaccinated)values('joe','2018-1-5','1');
insert into cat(name, rescued, vaccinated)values('leo','2017-3-21','0');
After running these sqls, save these as schema.sql (table) and data.sql (sqls to insert) in resources folder.



Create a model folder and a Cat.java:
Write as follows inside Cat.java
package com.blogspot.noteoneverything.chatboard.model;

import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Cat{
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;
    private String name;
    private Date rescued;
    private Boolean vaccinated;
    public long getId(){
        return id;
    }
    public void setId(long id){
        this.id = id;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
    public Date getRescued(){
        return rescued;
    }
    public void setRescued(Date rescued){
        this.rescued = rescued;
    }
    public Boolean getVaccinated(){
        return vaccinated;
    }
    public void setVaccinated(Boolean vaccinated){
        this.vaccinated = vaccinated;
    }
}
We will create a repository file. Create "dao" folder and CatRepository.java:

Then write as follows inside CatRepository.java:
package com.blogspot.noteoneverything.chatboard.dao;

import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

import com.blogspot.noteoneverything.chatboard.model.Cat;

@Repository
public interface CatRepository extends CrudRepository<Cat,Long>{
    Cat findByName(String name);
}
(We are extending CrudRepository now but JpaRepository is more popular.)
We will create service files. Create a "service" folder, then CatService.java and CatServiceImpl.java.

Write as follows in CatService.java:
package com.blogspot.noteoneverything.chatboard.service;
import java.util.Date;
import java.util.List;
public interface CatService {
        void addCat(String name, Date rescued, Boolean vaccinated);
        void deleteCat(String name, Long id);
        List atriskcats(Date rescued);
        long getGeneratedKey(String name, Date rescued, Boolean vaccinated);
}
Write as follows in CatServiceImpl.java:
package com.blogspot.noteoneverything.chatboard.service;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.text.Format;
import java.text.SimpleDateFormat;
import java.text.DateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
 
import javax.sql.DataSource;
 
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCreator;
import org.springframework.jdbc.core.ResultSetExtractor;
import org.springframework.jdbc.support.GeneratedKeyHolder;
import org.springframework.jdbc.support.KeyHolder;
import org.springframework.stereotype.Service;
 
@Service
public class CatServiceImpl implements CatService {
        @Autowired
        private DataSource dataSource;
        private JdbcTemplate jdbcTemplate;
        private long generatedKey;
        private String rescuedstring;
 
        public void setDataSource(DataSource dataSource) {
                this.dataSource = dataSource;
                this.jdbcTemplate = new JdbcTemplate(dataSource);
        }
        
        public void addCat(String name, Date rescued, Boolean vaccinated){
                JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
                jdbcTemplate.update("INSERT INTO cat(name,rescued,vaccinated)VALUES(?,?,?)",name,rescued,vaccinated );
        }
        
        public void deleteCat(String name, Long id){
                JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
                jdbcTemplate.update("DELETE FROM cat WHERE name='"+name+"' AND id="+id);
        }
        
        public List atriskcats(Date rescued){
                DateFormat df = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
                String stringRescued = df.format(rescued);
                String sql = "SELECT * FROM cat WHERE rescued < '"+ stringRescued +"' AND vaccinated = '0'";
                List catList = new ArrayList();
                JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
                jdbcTemplate.query(sql, new ResultSetExtractor() {
                        public List extractData(ResultSet rs) throws SQLException {
                            while (rs.next()) {
                                    String name = rs.getString("name");
                                    catList.add(name);
                            }
                            return catList;
                        }
                    }
                );
                System.out.println("catlist");
                return catList;        
        }
 
        public long getGeneratedKey(String name, Date rescued, Boolean vaccinated) {
                String sql ="INSERT INTO cat(name,rescued,vaccinated) VALUES(?,?,?)";
                JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
                KeyHolder holder = new GeneratedKeyHolder();
                java.sql.Date rescuedsql = new java.sql.Date(rescued.getTime());
                System.out.println(rescuedsql);
                jdbcTemplate.update(new PreparedStatementCreator() {
                public PreparedStatement createPreparedStatement(Connection connection) throws SQLException {
                        PreparedStatement statement = connection.prepareStatement(sql.toString(),
                                        Statement.RETURN_GENERATED_KEYS);
                        statement.setString(1, name);
                        statement.setDate(2, rescuedsql );
                        statement.setBoolean(3, vaccinated);
                        return statement;
                }
                }, holder);
                generatedKey = holder.getKey().longValue();
                System.out.println("generated key is " + generatedKey);
                return generatedKey;
        }
 
}
We will create a controller now. Create "controller" folder and CatController.java inside.

Write as follows inside CatController.java.
package com.blogspot.noteoneverything.chatboard.controller;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.text.SimpleDateFormat;
 
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.beans.propertyeditors.CustomDateEditor;
 
import com.blogspot.noteoneverything.chatboard.dao.CatRepository;
import com.blogspot.noteoneverything.chatboard.model.Cat;
import com.blogspot.noteoneverything.chatboard.service.CatService;
 
@Controller
public class CatController {
        @Autowired
        private CatRepository catrepository;
        @Autowired
        private CatService catservice;
        private ArrayList catModelList;
        private List<String> catrisklist = null;
        
        @GetMapping(value = "/")
        public String cathome(
                @RequestParam(value = "search", required = false) 
                @DateTimeFormat(pattern = "yyyy-MM-dd") Date q,
                Model model) {
                        if (q != null) {
                                catModelList = new ArrayList();
                                System.out.println("q is = " + q);
                                catrisklist = catservice.atriskcats(q);
                                for (String name : catrisklist) {
                                        System.out.println("Cats in repository are : " + catrepository.findAll());
                                        Cat catgy = catrepository.findByName(name);
                                        System.out.println(catgy.toString() + "catgy name : " + catgy.getName());
                                        catModelList.add(catgy);
                                        System.out.println("This cat's name is : " + catgy.getName());
                                }
                        }
                        model.addAttribute("search", catModelList);
                        model.addAttribute("cats", catrepository.findAll());
                        return "index";
                }
 
        @PostMapping(value = "/")
        public String addcat(@RequestParam("name") String name,
                        @RequestParam("rescued") @DateTimeFormat(pattern = "yyyy-MM-dd") Date rescued,
                        @RequestParam("vaccinated") Boolean vaccinated, Model model) {
                catservice.addACat(name, rescued, vaccinated);
                System.out.println("name = " + name + ",rescued = " + rescued + ", vaccinated = " + vaccinated);
                return "redirect:/";
        }
 
        @PostMapping(value = "/delete")
        public String deleteCat(@RequestParam("name") String name,
                        @RequestParam("id") Long id) {
                catservice.deleteADOG(name, id);
                System.out.println("Cat named = " + name + "was removed from our database. Hopefully he or she was adopted.");
                return "redirect:/";
 
        }
        
        @PostMapping(value = "/genkey")
        public String genkey(@RequestParam("name") String name,
                        @RequestParam("rescued") @DateTimeFormat(pattern = "yyyy-MM-dd") Date rescued,
                        @RequestParam("vaccinated") Boolean vaccinated, Model model) {
                catservice.getGeneratedKey(name, rescued, vaccinated);
                System.out.println("name = " + name + ",rescued = " + rescued + ", vaccinated = " + vaccinated);
                return "redirect:/";
        }
 
}
The catrepository.findAll() used in this class can be used like also:
   //all cats here
   Iterable cats = catrepository.findAll();

At last, add index.html in resources folder.

Write as follows inside:
<!DOCTYPE html>
<html lang="en">
    <head>
        <!-- META SECTION -->
        <title>Cat JdbcTemplate, Thymeleaf, JPA Example</title>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
        <meta http-equiv="X-UA-Compatible" content="IE=edge" />
        <meta name="viewport" content="width=device-width, initial-scale=1" />
        <!-- END META SECTION -->
        <!--  BEGIN STYLE -->
        <style>
            table, th, td {
            border: 1px solid black;
            padding: 1px;
            }
        </style>
        <!--  END STYLE -->
    </head>
    <body>
        <div>
            <h2>Current Cats In Rescue</h2>
            <table>
                <thead>
                    <tr>
                        <th>ID</th>
                        <th>Name</th>
                        <th>Rescue Date</th>
                        <th>Vaccinated</th>
                    </tr>
                </thead>
                <tbody>
                    <tr th:each="cats : ${cats}">
                        <td th:text="${cats.id}">Text ...</td>
                        <td th:text="${cats.name}">Text ...</td>
                        <td th:text="${cats.rescued}">Text ...</td>
                        <td th:text="${cats.vaccinated}">Text...</td>
                    </tr>
                </tbody>
            </table>
        </div>
        <!--  begin form for finding at risk cats -->
        <h2>Find Cats That Need Vaccines</h2>
        <form action="#" th:action="@{/}" th:object="${search}">
            <label for="search_input">Search:</label> <input name="search"
                id="search"  >
            </input>
            <div th:if="${not #lists.isEmpty(search)}">
                <h3>Search Results Of At Risk Cats</h3>
                <table>
                    <thead>
                        <tr>
                            <th>ID</th>
                            <th>Name</th>
                            <th>Vaccinated</th>
                            <th>Rescued</th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr th:each="search : ${search}">
                            <td th:text="${search.id}">Text ...</td>
                            <td th:text="${search.name}">Text ...</td>
                            <td th:text="${search.vaccinated}">Text ...</td>
                            <td th:text="${search.rescued}">Text...</td>
                        </tr>
                    </tbody>
                </table>
            </div>
        </form>
        <div>
            <h2>Add A Cat</h2>
            <form action="#" th:action="@{/}" method="post">
                <label>Name<input type="text" name="name" id="name"></input></label>
                <label>Vaccinated<input type="text" name="vaccinated" id="vaccinated"></input></label>
                <label>Rescued<input type="text" name="rescued" id="rescued"></input></label>
                <input type="submit" value="Submit"></input>
            </form>
        </div>
        <div>
            <h2>Delete A Cat</h2>
            <form action="/delete" th:action="@{/delete}" method="post">
                <label>Name<input type="text" name="name" id="name"></input></label>
                <label>ID<input type="text" name="id" id="id"></input></label>
                <input type="submit" value="Submit"></input>
            </form>
        </div>
        <div>
            <h2>Return Generated Key When Adding A Cat</h2>
            <form action="/genkey" th:action="@{/genkey}" method="post">
                <label>Name<input type="text" name="name" id="name"></input></label>
                <label>Vaccinated<input type="text" name="vaccinated" id="vaccinated"></input></label>
                <label>Rescued<input type="text" name="rescued" id="rescued"></input></label>
                <input type="submit" value="Submit"></input>
            </form>
        </div>
    </body>
</html>

Result:

References