I get the error.
java.lang.NullPointerException
at org.springframework.orm.hibernate3.support.HibernateDaoSupport.getSession(HibernateDaoSupport.java:143)
at com.walladverts.model.dao.UserDao.findByUsername(UserDao.java:25)
while accessing getSession() in findByUsername
package com.walladverts.model.dao;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Restrictions;
import org.springframework.stereotype.Repository;
import com.walladverts.exceptions.DataNotFoundException;
import com.walladverts.model.entities.User;
import com.walladverts.util.CustomHibernateDaoSupport;#
Repository("userDao")
public class UserDao extends CustomHibernateDaoSupport {
public void save(User user) {
getHibernateTemplate().save(user);
}
public void delete(User user) {
getHibernateTemplate().delete(user);
}
public User findByUsername(String username) throws DataNotFoundException {
Session session = getSession();
Criteria crit = session.createCriteria(User.class);
System.out.println(username);
crit.add(Restrictions.eq("username", username));
crit.setMaxResults(1);
List < User > users = crit.list();
System.out.println(users);
if (users.size() < 1) {
throw new DataNotFoundException();
}
return users.get(0);
}
}
Parent class:
package com.walladverts.util;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
public abstract class CustomHibernateDaoSupport extends HibernateDaoSupport {#
Autowired
public void init(SessionFactory factory) {
setSessionFactory(factory);
}
}
Does anybody has an idea why this occurs? It freezes me for developing.
EDIT:
It happens when Spring Secure tries to sign in an user. Also my SessionFactory is working OK when calling this method from Controller.
public abstract class CustomHibernateDaoSupport extends HibernateDaoSupport {
#Autowired
#Qualifier("sessionFactory")
private SessionFactory sessionFactory；
public Session getSession() {
return sessionFactory.getCurrentSession();
}
}
public User findByUsername(String username) throws DataNotFoundException {
Session session = getSession();
// do sth
}
HibernateDaoSupport for a very long time has final getSessionFactory and setSessionFactory methods that can't be overriden.
It was initially supposed to mitigate xml configuration via <property name="sessionFactory" ref="sessionFactory" /> but mixing it #Autowired annotation is also possible.
The you would have to just call getSession() method when needed.
Related
I tried to create an abstract Dao. I use Spring + Hibernate.
Here's my code.
Main class with configuration:
package ru.makaek.growbox.api;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.core.env.Environment;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.hibernate5.HibernateTransactionManager;
import org.springframework.orm.hibernate5.LocalSessionFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.sql.DataSource;
#ComponentScan(value = "ru.makaek.growbox")
#EnableAutoConfiguration(exclude = HibernateJpaAutoConfiguration.class)
#EnableTransactionManagement
#SpringBootApplication
public class Application {
#Autowired
private Environment env;
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public DataSource getDataSource() {
DriverManagerDataSource dataSource = new DriverManagerDataSource();
dataSource.setDriverClassName(env.getRequiredProperty("datasource.driver"));
dataSource.setUrl(env.getRequiredProperty("datasource.url"));
dataSource.setUsername(env.getRequiredProperty("datasource.username"));
dataSource.setPassword(env.getRequiredProperty("datasource.password"));
return dataSource;
}
#Bean
public LocalSessionFactoryBean getSessionFactory() {
LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
sessionFactory.setDataSource(getDataSource());
sessionFactory.setPackagesToScan(new String[]{"ru.makaek.growbox"});
return sessionFactory;
}
#Bean
public HibernateTransactionManager getTransactionManager(SessionFactory sessionFactory) {
HibernateTransactionManager txManager = new HibernateTransactionManager();
txManager.setSessionFactory(sessionFactory);
return txManager;
}
}
Rest controller
package ru.makaek.growbox.api.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import ru.makaek.growbox.api.model.data.entities.Device;
import ru.makaek.growbox.api.service.IStructureService;
#RestController
public class DeviceController extends AbstractController {
#Autowired
IStructureService structureService;
#RequestMapping(value = "/devices", method = RequestMethod.POST)
public Answer addDevice(#RequestBody Device device) {
structureService.addDevice(device);
return ok("Device has been added");
}
#RequestMapping(value = "/devices", method = RequestMethod.GET)
public Answer getDevices() {
return ok(structureService.getDevices());
}
#RequestMapping(value = "/devices/{deviceId}", method = RequestMethod.GET)
public Answer getDevice(#PathVariable Long deviceId) {
return ok(structureService.getDevice(deviceId));
}
}
Service layer. Interface
package ru.makaek.growbox.api.service;
import ru.makaek.growbox.api.model.data.entities.Device;
import java.util.List;
public interface IStructureService {
void addDevice(Device device);
List<Device> getDevices();
Device getDevice(Long deviceId);
}
Service layer. Implementation
package ru.makaek.growbox.api.service;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import ru.makaek.growbox.api.model.data.dao.base.IDao;
import ru.makaek.growbox.api.model.data.entities.Device;
import java.util.List;
#Service
#Transactional
public class StructureService implements IStructureService {
IDao<Device> deviceDao;
#Autowired
public void setDao(IDao<Device> dao) {
deviceDao = dao;
dao.setClazz(Device.class);
}
#Override
public void addDevice(Device device) {
deviceDao.create(device);
}
#Override
public List<Device> getDevices() {
return deviceDao.findAll();
}
#Override
public Device getDevice(Long deviceId) {
return deviceDao.findOne(deviceId);
}
}
Entity
package ru.makaek.growbox.api.model.data.entities;
import lombok.Data;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
#Entity(name = "devices")
#Data public class Device extends BaseEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
}
DAO. Interface
package ru.makaek.growbox.api.model.data.dao.base;
import ru.makaek.growbox.api.model.data.entities.BaseEntity;
import java.util.List;
public interface IDao<T extends BaseEntity> {
T findOne(final long id);
void setClazz(Class<T> clazz);
List<T> findAll();
void create(final T entity);
T update(final T entity);
void delete(final T entity);
void deleteById(final long entityId);
}
Abstract DAO
package ru.makaek.growbox.api.model.data.dao.base;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import ru.makaek.growbox.api.model.data.entities.BaseEntity;
import ru.makaek.growbox.api.util.GBException;
import java.util.List;
public abstract class AbstractDao<T extends BaseEntity> implements IDao<T> {
private Class<T> clazz;
#Autowired
private SessionFactory sessionFactory;
public final void setClazz(Class<T> clazz) {
this.clazz = clazz;
}
public T findOne(long id) {
try {
return (T) getCurrentSession().get(clazz, id);
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
public List<T> findAll() {
try {
return getCurrentSession().createQuery("from " + clazz.getName()).list();
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
public void create(T entity) {
try {
getCurrentSession().persist(entity);
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
public T update(T entity) {
try {
return (T) getCurrentSession().merge(entity);
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
public void delete(T entity) {
try {
getCurrentSession().delete(entity);
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
public void deleteById(long entityId) {
try {
T entity = findOne(entityId);
delete(entity);
} catch (Exception e) {
throw new GBException.InternalError(e.getMessage());
}
}
protected final Session getCurrentSession() {
return sessionFactory.getCurrentSession();
}
}
DAO. Implementation
package ru.makaek.growbox.api.model.data.dao;
import org.springframework.stereotype.Repository;
import ru.makaek.growbox.api.model.data.dao.base.AbstractDao;
import ru.makaek.growbox.api.model.data.entities.Device;
#Repository
public class DeviceDao extends AbstractDao<Device> {
}
I have one trouble. When I call GET http://host:port/devices API method I have null in the clazz variable in the AbstractDao.findAll() method. When I was debugging the code i found one interesting thing: in the service layer method deviceDao.getClazz() returned needed clazz (not null). But in method AbstractDao.findAll() I have null in clazz variable. Why? Please help.
Sorry for my English and formulation. I'm new in this site, Spring and English
You are overcomplicating things. Because you are using Spring Boot it is possible to just create generic interface that extends CrudRepository and add the methods you need and are not already present in there.
Take a look here https://docs.spring.io/spring-data/data-commons/docs/1.6.1.RELEASE/reference/html/repositories.html
I started to develop APIs for iOS app using Java Spring MVC two months ago.
I'll explain my question with an example for clarification purpose.
Let's say I want to update a user's name.
My mySQL user table has columns: id, user_id, email, display_name.
My approach was:
define user:
User.java:
package bean;
public class User {
String displayName;
String email;
String userId;
getters/setters...
}
2.define a DAO:
UserDao.java:
package dao;
import bean.StandardResponse;
public interface UserDao {
public StandardResponse updateUserName(String user_id,String userName);
}
UserDaoImpl.java:
package implement;
import bean.User;
import common.DatabaseConnect;
public UserDaoImpl implements UserDao {
private DatabaseConnect dbConnect;
public UserDaoImpl(DatabaseConnect dbConnect) {
this.dbConnect = dbConnect;
}
public StandardResponse updateUserName(userId,userName) {
if ((userId == null || userId.isEmpty()) ||(userName == null || userName.isEmpty())) return new StandardResponse("Error","Parameters not set!");
String sql = null;
Statement smt = dbConnect.createDataBaseConnectResourse();
StandardResponse result = new StandardResponse("Error","Fail to update the record!");
sql = "update User set user_name="+userName+" where user_id='"+userId+"'";
int updateResult = 0;
try {
updateResult = smt.executeUpdate(sql);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
dbConnect.closeDatabaseConnectResource();
}
if (updateResult == 1) {
result = new StandardResponse("Success","The record has been updated!");
}
return result;
}
}
3.controller
import org.springframework.stereotype.Controller;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import bean.StandardResponse;
import bean.User;
import common.DatabaseConnect;
import common.SpringApplicationContext;
import dao.UserDao;
import implement.UserDAOImpl;
#Controller
#RestController
#RequestMapping("user")
public class UserController {
DatabaseConnect dbConnect = SpringApplicationContext.getApplicationContext().getBean("databaseConnect", DatabaseConnect.class);
UserDao uiObject = new UserDaoImpl(dbConnect);
#RequestMapping(value = "/updateUserName", method = RequestMethod.POST)
public StandardResponse updateUserName(HttpServletRequest request, HttpServletResponse reponses, Model model) {
StandardResponse srObject = uiObject.updateUserName(request.getparameter("userId"),request.getParameter("userName"));
return srObject;
}
}
I just put the crucial classes here. I believe you can understand what I am doing here. So if someone access the URL:****/user/updateUserName providing the userId and userName, he can update the user name of that record. It is functionalbe.
I used the same approach and finished the whole project. It is working. Then, I asked an experienced programmer to look at my code since I figured out all these based on my own understanding. I would like to know how did they do in industry. He gave me some valuable comments.
The whole structure is wrong. I shouldn't have logics in my dao. I should at least have dao, service and action layers. dao only handles database access, service handles all the logic and action handels communication and decide which service to call.
It is very bad approach to hand written SQL in the code. I should use Hibernate.
I should use control inverse and dependency injection.(I am not dealing with this in this post.)
So I started to update my codes to use Hibernate.
define user:
User.java:
package model;
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="User")
public class User {
#Id
#Column(name="id")
#GeneratedValue(strategy=GenerationType.IDENTITY)
private int id;
#Column(name = "user_id")
private String userId;
#Column(name = "user_name")
private String displayName;
#Column(name = "email")
private String emai;
all getters/setters...
}
dao:
UserDao.java:
package dao;
import model.User;
import java.util.List;
public interface UserDAO {
public void updateUser(User p);
other methods....
}
UserDaoImpl.java
package dao;
import model.User;
import java.util.List;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.stereotype.Repository;
import model.User;
#Repository
public class PersonDAOImpl implements PersonDAO {
private SessionFactory sessionFactory;
public void setSessionFactory(SessionFactory sf){
this.sessionFactory = sf;
}
#Override
public void updatePerson(Person p) {
Session session = this.sessionFactory.getCurrentSession();
session.update(p);
}
implementations of other methods....
}
service:
UserService.java:
package service;
import java.util.List;
import model.User;
public interface UserService {
public void updateUser(User p);
other methods....
}
UserServiceImpl.java:
package service;
import java.util.List;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import dao.UserDAO;
import model.User;
#Service
public class UserServiceImpl implements UserService {
private UserDAO userDAO;
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
#Override
#Transactional
public void updateUser(User p) {
this.userDAO.updateUser(p);
}
implementation of other methods...
}
Now, I just need to write a class to handle the request and call this updateUser service. The whole structure looks better than mine. However, the request won't gave me the whole user object. All I can get is user_id and user_name. I am also not allowed to put logics in dao. So I have to query the table first to get the whole user object and then update the user_name. Comparing to what I used to do, one SQL handles the update. Now using Hibernate, I need 1 query and 1 update.
I found a solution on StackOverflow that I can use HQL to do this in one step. But I though the purpose for using Hibernate is to free us from writing the SQL. If I need to write HQL, why don't I just keep using the writing SQL approach.
So is there a way to do update with Hibernate without query the table first in this structure? Or this is a trade-off for better structure?
I am sorry that I used a really long example for this question. But I couldn't think of other ways to explain the whole story clearly.
So is there a way to do update with Hibernate without query the table first in this structure? Or this is a trade-off for better structure?
Thereis NO tradeoff, you can do updates with HQL(Hibernate Query Language) as well like how you do in SQL.
You can look at the following code:
UserDAOImpl class:
#Repository
//you are calling this in ur code as PersonDAOImpl..change it to UserDAOImpl
public class UserDAOImpl implements UserDAO {
private SessionFactory sessionFactory;
public void setSessionFactory(SessionFactory sf){
this.sessionFactory = sf;
}
#Override
public int updateUser(String userId, String userName) {
Session session = this.sessionFactory.getCurrentSession();
Query query = session.createQuery("update User set userName =:userName where userId = :userName ");
query.setString("userName", userName);
query.setString(userName, userName);
int result = query.executeUpdate();
return result;
}
}
UserServiceImpl class:
#Service
public class UserServiceImpl implements UserService {
private UserDAO userDAO;
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
#Override
#Transactional
public void updateUserName(String userId, String userName) {
if(userId !=null && userName != null) {
int result = this.userDAO.updateUser(userId, userName);
if(result==0) //userid not available {
//if userid is NOT available, what to do? check your requirement and handle properly
}
}
} else {
//throw exception
}
}
implementation of other methods...
}
Controller Class:
#Controller
#RestController
#RequestMapping("user")
public class UserController {
#Autowired
private UserService userService;
#RequestMapping(value = "/updateUserName", method = RequestMethod.POST)
public StandardResponse updateUserName(HttpServletRequest request, HttpServletResponse reponses, Model model) {
StandardResponse srObject = userService.updateUserName(request.getparameter("userId"),request.getParameter("userName"));
return srObject;
}
}
I'm using Vaadin 7.5.6, Vaadins Spring 1.0.0, the Vaadin4Spring Managed Security Extension 0.0.7-SNAPSHOT and Tomcat8.
Currently, I got a configuration class which implements the AuthenticationManagerConfigurer interface:
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.vaadin.spring.security.annotation.EnableVaadinManagedSecurity;
import org.vaadin.spring.security.config.AuthenticationManagerConfigurer;
import com.vaadin.server.CustomizedSystemMessages;
import com.vaadin.server.SystemMessages;
import com.vaadin.server.SystemMessagesInfo;
import com.vaadin.server.SystemMessagesProvider;
import de.blume2000.kiss.hibernate.dto.User;
import de.blume2000.kiss.hibernate.services.UserService;
import de.blume2000.kiss.utils.EncryptionUtil;
#Configuration
#EnableVaadinManagedSecurity
public class SecurityConfiguration implements AuthenticationManagerConfigurer
{
#Autowired
UserService userService;
#Override
public void configure(AuthenticationManagerBuilder auth) throws Exception
{
List<User> users = userService.findAll();
if (users == null)
return;
for (User user : users)
{
String encryptedPassword = EncryptionUtil.decryptPassword(user.getPassword(), user.getSalt());
auth.inMemoryAuthentication().withUser(user.getUsername()).password(encryptedPassword).roles(user.getRole());
}
}
/**
* Provide custom system messages to make sure the application is reloaded when the session expires.
*/
#SuppressWarnings("serial")
#Bean
SystemMessagesProvider systemMessagesProvider()
{
return new SystemMessagesProvider()
{
#Override
public SystemMessages getSystemMessages(SystemMessagesInfo systemMessagesInfo)
{
CustomizedSystemMessages systemMessages = new CustomizedSystemMessages();
systemMessages.setSessionExpiredNotificationEnabled(false);
return systemMessages;
}
};
}
}
Now if the user did a login he has the option to edit his user account settings. This changes the user object in the database (e.g. the username for login). Now if he does a logout, i want the application to reload the userlist, so the user can use his new username. How is this possible?
Regards
shinchillahh
In short, replace your in-memory authentication with DAO authentication.
Please note that in the example below UserDetailsService userService is the Spring core interface, and UserRepository userRepository is the DAO for your users (aka UserService userService in your example).
1. Configuration
#Configuration
public class Authorization extends GlobalAuthenticationConfigurerAdapter {
#Autowired
private UserDetailsService userService;
#Override
public void init(AuthenticationManagerBuilder auth) throws Exception {
auth.userDetailsService(userService).passwordEncoder(passwordEncoder());
}
#Bean
public PasswordEncoder passwordEncoder(){
return new BCryptPasswordEncoder();
}
}
2. Service providing user details
#Service
public class UserService implements UserDetailsService {
#Autowired
private UserRepository userRepository;
#Override
#Transactional(readOnly = true)
public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
User user = userRepository.findByUsername(username);
if (user == null) {
throw new UsernameNotFoundException(username);
}
return user;
}
}
Whenever I try to get SpringMVC's ApplicationContext, a NullPointerException is thrown.
This is my userDao:
package com.markor.smarthome.dao;
import com.markor.smarthome.entities.Users;
import com.markor.smarthome.utilites.SpringContextUtil;
import com.markor.smarthome.utilites.StringUtilty;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;
import java.util.HashMap;
import java.util.Map;
/**
* Created by litongjie on 2015/5/12.
*/
public class UserDao {
private JdbcTemplate jdbcTemplate = (JdbcTemplate) SpringContextUtil.getBeans("jdbcTemplate");
private String isExistSql = "SELECT * FROM users WHERE user_id=?";
private String addUserSql = "INSERT INTO users(`user_id`,`password`,`name`,`email`,`note`)VALUES(?,?,?,?,?)";
public boolean isExist(String userID) {
Users user = jdbcTemplate.queryForObject(isExistSql, Users.class, userID);
//如果为空 返回false不存在
if (StringUtilty.isNullOrEmpty(user.getUser_id())) {
return false;
} else return true;
}
public int AddUser(Users user) {
System.out.println("begen");
Map<String, Object> map = new HashMap<>();
map.put("user_id", user.getUser_id());
map.put("password", user.getPassword());
map.put("name", user.getName());
map.put("email", user.getEmail());
map.put("note", user.getNote());
int i = jdbcTemplate.update(addUserSql, map);
return i;
}
public static void main(String[] args) {
System.out.println("main begin");
Users users = new Users();
users.setUser_id("123");
users.setName("LI");
users.setNote("444");
System.out.println("user end"+users);
UserDao userDao = new UserDao();
System.out.print(userDao.AddUser(users));
}
}
This is my SpringContextUtil
package com.markor.smarthome.utilites;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.test.context.testng.AbstractTestNGSpringContextTests;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import javax.servlet.ServletContext;
/**
* 获取Spring上下文及国际化
*
* #author bingchuan -->www.vijun.com
*/
public class SpringContextUtil implements ApplicationContextAware {
private static ApplicationContext application = null;
#Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.application = applicationContext;
}
public static ApplicationContext getApplicationContext() {
return application;
}
public static Object getBeans(String beanname) {
ApplicationContext applicationContext = getApplicationContext();
return applicationContext.getBean(beanname);
}
I tried using some other's answers, but it didn't work either. Here is my exception:
Exception in thread "main" java.lang.NullPointerException
at com.markor.smarthome.utilites.SpringContextUtil.getBeans(SpringContextUtil.java: 31)
at com.markor.smarthome.dao.UserDao.(UserDao.java:18)
at com.markor.smarthome.dao.UserDao.main(UserDao.java:50)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
That looks completely wrong. Where did you start up your spring context?
If you want to use it somewhere in the main() method, you have to write something like this:
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("/application-context.xml");
(but in that case you don't need SpringContextUtil, because you already have your context).
But why don't you add UserDao to the context and let spring inject jdbcTemplate bean into it?
something like this:
UserDao:
public class UserDao {
#Autowire
private JdbcTemplate jdbcTemplate;
.....
spring context:
<bean id="jdbcTemplate" class=.../>
<bean id="userDao" class="com.markor.smarthome.dao.UserDao"/>
I am in need of a custom constraint which validates that a value is unique. I have been searching the internet for a long time to find a good example. The one I found is using hibernate template which is not recommended anymore so I was wondering if anyone had the expertise to "translate" this code so that it doesn't use the templates. I have tried to do it myself but I don't understand what the getter and setter are for. Here is the code which I got from this helpful guide.
package com.omgo.security.domain.validator;
import java.io.Serializable;
import java.util.List;
import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.orm.hibernate3.HibernateTemplate;
public class UniqueIDValidator implements ConstraintValidator<Unique, Serializable> {
HibernateTemplate hibernateTemplate;
private Class<?> entityClass;
private String uniqueField;
public void initialize(Unique unique) {
entityClass = unique.entity();
uniqueField = unique.property();
}
public boolean isValid(Serializable property, ConstraintValidatorContext cvContext) {
String query = String.format("from %s where %s = ? ", entityClass.getName(), uniqueField);
List<?> list = hibernateTemplate.find(query, property);
return list != null && list.size() > 0;
}
public SessionFactory getSessionFactory() {
return hibernateTemplate != null ? hibernateTemplate.getSessionFactory() : null;
}
#Autowired
public void setSessionFactory(SessionFactory sessionFactory) {
this.hibernateTemplate = new HibernateTemplate(sessionFactory);
}
}
Thank you for your help.
/D
Update
After changing the code I am getting this error:
org.hibernate.HibernateException: No Hibernate Session bound to thread, and configuration does not allow creation of non-transactional one here
So I'm thinking that maybe I haven't injected the SessionFactory properly?
UniqueIdValidator.java:
package testapp.mis.validator;
import java.io.Serializable;
import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import org.hibernate.Criteria;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Restrictions;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.transaction.annotation.Transactional; // Added in update 2
public class UniqueIdValidator implements ConstraintValidator<Unique, Serializable> {
#Autowired(required=true)
private SessionFactory sessionFactory;
private Class<?> entityClass;
private String uniqueField;
public void initialize(Unique unique) {
entityClass = unique.entity();
uniqueField = unique.property();
}
#Transactional //Added in update 2 and validation works after that
public boolean isValid(Serializable property, ConstraintValidatorContext cvContext) {
Criteria crit = sessionFactory.getCurrentSession().createCriteria(entityClass);
crit.add(Restrictions.eq(uniqueField, property));
return crit.list().isEmpty();
}
Update 2
I got it working by adding #Transactional in the code.
That uses plain HQL, you can achieve something simpler by using the Criteria API, something like:
public boolean isValid(Serializable property, ConstraintValidatorContext cvContext) {
Criteria crit = sessionFactory.getCurrentSession().createCriteria(entityClass);
crit.add(Restrictions.eq(uniqueField, property));
return crit.list().isEmpty();
}
That should check for uniqueness.
Instead of injecting the hibernate template, just inject the SessionFactory which you also should have configured in your spring context.
Hope you find it useful!