複数のテーブルが関連して動かしたい場合は、「アソシエーション」という機能によりエンティティ同士を連携して処理する
＠OneToOne,@OneToMany, @ManyToOne, @ManyToMany
package com.example.demo;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import org.hibernate.validator.constraints.NotEmpty;
@Entity
@Table(name = "msgdata")
public class MsgData {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column
@NotNull
private long id;
@Column
private String title;
@Column(nullable = false)
@NotEmpty
private String message;
@ManyToOne
private MyData mydata;
public MsgData() {
super();
mydata = new MyData();
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public MyData getMyData() {
return mydata;
}
public void setMydata(MyData mydata) {
this.mydata = mydata;
}
}
MsgDataRepository.java
package com.example.demo.repositories;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
import com.example.demo.MsgData;
@Repository
public interface MsgDataRepository extends JpaRepository<MsgData, Long>{
}
MsgDataDao.java
package com.example.demo;
import java.io.Serializable;
import java.util.List;
public interface MsgDataDao<T> {
public List<MsgData> getAll();
public MsgData findById(long id);
}
MsgDataDaoImpl.java
package com.example.demo;
import java.util.List;
import javax.persistence.EntityManager;
import org.springframework.stereotype.Repository;
@SuppressWarnings("rawtypes")
@Repository
public class MsgDataDaoImpl implements MsgDataDao<MsgDataDao>{
private EntityManager entityManager;
public MsgDataDaoImpl() {
super();
}
public MsgDataDaoImpl(EntityManager manager) {
entityManager = manager;
}
@SuppressWarnings("unchecked")
@Override
public List<MsgData> getAll(){
return entityManager
.createQuery("from MsgData")
.getResultList();
}
@Override
public MsgData findById(long id) {
return (MsgData)entityManager
.createQuery("from MsgData where id = "
+ id).getSingleResult();
}
}
showMsgData.html
<h1 th:text="${title}">MyMsg page</h1>
<p th:text="${msg}"></p>
<table>
<form method="post" action="/msg" th:object="${formModel}">
<input type="hidden" name="id" th:value="*{id}">
<tr>
<td><label for="title">タイトル</label></td>
<td><input type="text" name="title" th:value="*{title}"></td>
</tr>
<tr>
<td><label for="message">メッセージ</label></td>
<td><textarea name="message" th:text="*{message}"></textarea></td>
</tr>
<tr>
<td><label for="mydata">MYDATA_ID</label></td>
<td><input type="text" name="mydata"></td>
</tr>
<tr>
<td></td>
<td><input type="submit"></td>
</tr>
</form>
</table>
<hr>
<table>
<tr><th>ID</th><th>名前</th><th>タイトル</th></tr>
<tr th:each="obj : ${datalist}">
<td th:text="${obj.id}"></td>
<td th:text="${obj.mydata.name}"></td>
<td th:text="${obj.title}"></td>
</tr>
</table>
MsgDataController.java
package com.example.demo;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.validation.Valid;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.Errors;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import com.example.demo.repositories.MsgDataRepository;
@Controller
public class MsgDataController {
@Autowired
MsgDataRepository repository;
@PersistenceContext
EntityManager entityManager;
MsgDataDaoImpl dao;
@RequestMapping(value = "/msg", method=RequestMethod.GET)
public ModelAndView msg(ModelAndView mav) {
mav.setViewName("showMsgData");
mav.addObject("title", "Sample");
mav.addObject("msg","MsgDataのsampleです");
MsgData msgdata = new MsgData();
mav.addObject("formModel", msgdata);
List<MsgData> list = (List<MsgData>)dao.getAll();
mav.addObject("datalist", list);
return mav;
}
@RequestMapping(value="/msg", method=RequestMethod.POST)
public ModelAndView msgform(
@Valid @ModelAttribute MsgData msgdata,
Errors result,
ModelAndView mav) {
if(result.hasErrors()) {
mav.setViewName("showMsgData");
mav.addObject("title", "Sample [Error]");
mav.addObject("msg", "値を再チェックして下さい");
return mav;
} else {
repository.saveAndFlush(msgdata);
return new ModelAndView("redirect:/msg");
}
}
@PostConstruct
public void init() {
System.out.println("ok");
dao = new MsgDataDaoImpl(entityManager);
}
}
んん？あれ？
