1
我有和NullPointerException在session.flush()後，我已經添加JPA註釋到我的豆。也許我有錯誤的註釋或有什麼在休眠緩存？NullPointerException在刷新[Java EE +休眠4. 3.5]
有我的用戶實體：
package com.viktor.solodoukhin.beans;
import javax.persistence.*;
import java.sql.Timestamp;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.sql.Date;
import java.util.List;
@Entity
@Table(name="tuser")
@Inheritance(strategy = InheritanceType.JOINED)
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name="user_id", unique=true, nullable=false)
private Long id;
@Column(name="first_name", nullable=false)
private String firstName;
@Column(name="last_name", nullable=false)
private String lastName;
@Column(name="email", unique=true)
private String email;
@Column(name="password")
private String password;
@Column(name="born_on")
private Date bornOn;
@Column(name="created_at")
private Timestamp createdAt;
@Column(name="updated_at")
private Timestamp updatedAt;
@Column(name="is_archived")
private short isArchived;
@Column(name="is_validated")
private short isValidated;
@OneToMany(mappedBy = "userId")
private List<Address> addresses;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
String hashedPassword = null;
try{
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(password.getBytes(), 0, password.length());
hashedPassword = new BigInteger(1, md.digest()).toString(16);
this.password = hashedPassword;
} catch(NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
public Date getBornOn() {
return bornOn;
}
public void setBornOn(Date bornOn) {
this.bornOn = bornOn;
}
public Timestamp getCreatedAt() {
return createdAt;
}
public void setCreatedAt(Timestamp createdAt) {
this.createdAt = createdAt;
}
public Timestamp getUpdatedAt() {
return updatedAt;
}
public void setUpdatedAt(Timestamp updatedAt) {
this.updatedAt = updatedAt;
}
public short getIsArchived() {
return isArchived;
}
public void setIsArchived(short isArchived) {
this.isArchived = isArchived;
}
public short getIsValidated() {
return isValidated;
}
public void setIsValidated(short isValidated) {
this.isValidated = isValidated;
}
public List<Address> getAddresses() {
return addresses;
}
public void setAddresses(List<Address> addresses) {
this.addresses = addresses;
}
}
的道是：
protected void saveOrUpdate(Object obj){
try{
startOperation();
session.saveOrUpdate(obj);
transaction.commit();
} catch(HibernateException e){
e.printStackTrace();
} finally {
flushAndClose();
}
}
HibernateUtil的代碼：
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
// Create the SessionFactory from hibernate.cfg.xml
return new Configuration().configure().buildSessionFactory();
} catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
System.err.println("SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
public static void shutdown() {
// Close caches and connection pools
getSessionFactory().close();
}
}
和代碼最後部分，我添加一個新用戶：
// We create our user
UserDao userDao = new UserDao();
User fabulous = new User();
fabulous.setFirstName(firstName);
fabulous.setLastName(lastName);
fabulous.setEmail(email);
fabulous.setPassword(password);
//fabulous.setCreatedAt(dt);
userDao.create(fabulous);
PS：創建方法：
(UserDao extends Dao)
public void create(User user) {
super.saveOrUpdate(user);
}
AND：flushAndClose（）方法
private void flushAndClose(){
session.flush();
session.close();
}
，當然！完全鬆懈！
java.lang.NullPointerException
com.viktor.solodoukhin.dao.Dao.flushAndClose(Dao.java:71)
com.viktor.solodoukhin.dao.Dao.saveOrUpdate(Dao.java:20)
com.viktor.solodoukhin.dao.UserDao.create(UserDao.java:14)
com.viktor.solodoukhin.forms.UserRegisterForm.registerUser(UserRegisterForm.java:91)
com.viktor.solodoukhin.servlets.Register.doPost(Register.java:26)
javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
編輯：我試圖把一個try/catch塊內的方法flushAndClose。 號我有這個slacktrace：
javax.servlet.ServletException: L''exécution de la servlet a lancé une exception
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
caused by
java.lang.ExceptionInInitializerError
com.viktor.solodoukhin.HibernateUtil.HibernateUtil.buildSessionFactory(HibernateUtil.java:16)
com.viktor.solodoukhin.HibernateUtil.HibernateUtil.<clinit>(HibernateUtil.java:7)
com.viktor.solodoukhin.dao.Dao.startOperation(Dao.java:66)
com.viktor.solodoukhin.dao.Dao.saveOrUpdate(Dao.java:14)
com.viktor.solodoukhin.dao.UserDao.create(UserDao.java:14)
com.viktor.solodoukhin.forms.UserRegisterForm.registerUser(UserRegisterForm.java:91)
com.viktor.solodoukhin.servlets.Register.doPost(Register.java:26)
javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
caused by
org.hibernate.AnnotationException: @Temporal should only be set on a java.util.Date or java.util.Calendar property: com.viktor.solodoukhin.beans.Register.dateEnd
org.hibernate.cfg.annotations.SimpleValueBinder.setType(SimpleValueBinder.java:179)
org.hibernate.cfg.annotations.PropertyBinder.makePropertyAndValue(PropertyBinder.java:195)
org.hibernate.cfg.annotations.PropertyBinder.makePropertyValueAndBind(PropertyBinder.java:216)
org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:2238)
org.hibernate.cfg.AnnotationBinder.processIdPropertiesIfNotAlready(AnnotationBinder.java:963)
org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:796)
org.hibernate.cfg.Configuration$MetadataSourceQueue.processAnnotatedClassesQueue(Configuration.java:3788)
org.hibernate.cfg.Configuration$MetadataSourceQueue.processMetadata(Configuration.java:3742)
org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1410)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1844)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1928)
com.viktor.solodoukhin.HibernateUtil.HibernateUtil.buildSessionFactory(HibernateUtil.java:12)
com.viktor.solodoukhin.HibernateUtil.HibernateUtil.<clinit>(HibernateUtil.java:7)
com.viktor.solodoukhin.dao.Dao.startOperation(Dao.java:66)
com.viktor.solodoukhin.dao.Dao.saveOrUpdate(Dao.java:14)
com.viktor.solodoukhin.dao.UserDao.create(UserDao.java:14)
com.viktor.solodoukhin.forms.UserRegisterForm.registerUser(UserRegisterForm.java:91)
com.viktor.solodoukhin.servlets.Register.doPost(Register.java:26)
javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
之前，我加入@Temporal註解和我已經刪除，因爲他們的IntelliJ哭了。所以這就是爲什麼我認爲緩存中有數據但是如何刪除它？！
請告訴我們'create'方法和'flushAndClose'方法。 – Shadov
'session'屬性似乎爲空。你如何檢索它？ –
'session.saveOrUpdate（）'沒有錯誤？ – Shadov