SpringBoot2 JPA解决懒加载异常的问题
jpa解决懒加载异常
在我上一遍文章上进行行修改，SpringBoot2实现JPA分页和排序分页
实体类上改：
@Entity
@Table(name="employee")
@JsonIgnoreProperties(value={"hibernateLazyInitializer","department"})
publicclassEmployee{
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
privateIntegerempId;
privateStringlastName;
privateStringemail;
@Temporal(TemporalType.DATE)
privateDatebirth;
@Temporal(TemporalType.TIMESTAMP)
privateDatecreateTime;
@ManyToOne(fetch=FetchType.LAZY)
@JoinColumn(name="dept_id")
privateDepartmentdepartment;
publicIntegergetEmpId(){
returnempId;
}
publicvoidsetEmpId(IntegerempId){
this.empId=empId;
}
publicStringgetLastName(){
returnlastName;
}
publicvoidsetLastName(StringlastName){
this.lastName=lastName;
}
publicStringgetEmail(){
returnemail;
}
publicvoidsetEmail(Stringemail){
this.email=email;
}
publicDategetBirth(){
returnbirth;
}
publicvoidsetBirth(Datebirth){
this.birth=birth;
}
publicDategetCreateTime(){
returncreateTime;
}
publicvoidsetCreateTime(DatecreateTime){
this.createTime=createTime;
}
publicDepartmentgetDepartment(){
returndepartment;
}
publicvoidsetDepartment(Departmentdepartment){
this.department=department;
}
}
控制器验证
importjava.util.Iterator;
@RestController
publicclassEmployeeController{
@Autowired
privateEmployeeServiceemployeeService;
@GetMapping("/emp")
publicPageshowPage(@RequestParam(value="page")Integerpage,@RequestParam(value="size")Integersize){
System.out.println("分页：page:"+page+";size:"+size);
returnemployeeService.getPage(page,size);
}
@GetMapping("/emp_sort")
publicPageshowSortPage(@RequestParam(value="page")Integerpage,@RequestParam(value="size")Integersize){
System.out.println("排序分页：page:"+page+";size:"+size);
Pagelist=employeeService.getPageSort(page,size);
Iteratorit=list.iterator();
while(it.hasNext()){
System.out.println("value:"+(it.next()).getDepartment().getDeptName());
}
returnlist;
}
}
我大概实现了一下，具体的如果大佬找到更好的方法或者发现我的方法是错的，希望各位大佬提醒一下！感谢！
补充：SpringBootjpa使用懒加载时，报异常：session失效
报异常:
couldnotinitializeproxy-noSession
1、在方法上加@Transactional注解，失败
2、在application.yml文件加上jpa.properties.open-in-view:true失败
3、在ResourceServerApplication.java启动文件中加上：
@Bean
publicOpenEntityManagerInViewFilteropenEntityManagerInViewFilter(){
returnnewOpenEntityManagerInViewFilter();
}
成功解决~
总结：
要解决nosession问题需要：
配置文件中加jpa.properties.open-in-view:true同时在启动文件中加@Bean
以上为个人经验，希望能给大家一个参考，也希望大家多多支持毛票票。如有错误或未考虑完全的地方，望不吝赐教。