我正在使用postman和springboot，我已经使用了GET/POST/DELETE请求，它们都工作正常，但是PUT请求不更新内容。
在intellij中，我使用这些文件：
Student.java(with它是setter和getter）：

@Entity
@Table
public class Student {
@Id
@SequenceGenerator(
        name="student_sequence",
        sequenceName="student_sequence",
        allocationSize = 1
)
@GeneratedValue(
        strategy = GenerationType.SEQUENCE,
        generator = "student_sequence"
)
private Long id;
private String name;

private LocalDate dob;
private  String email;
@Transient
private Integer age;

StudentController.java ：

@PutMapping(path ="{studentId}")
public void updateStudent(
        @PathVariable("studentId") Long studentId,
        @RequestParam(required = false) String name,
        @RequestParam(required = false) String email)
{
    studentService.updateStudent(studentId,name,email);
}

StudentService.java ：

@Transactional
public void updateStudent(Long studentId,String name, String email)
{
   Student student = studentRepository.findById(studentId)
           .orElseThrow(() -> new IllegalStateException(
                   "student with id="+studentId+"does not exist"));
   if (name !=null && name.length()>0  && !Objects.equals(student.getName(),name))
   {
       student.setName(name);
   }
   if (email !=null && email.length()>0 && !Objects.equals(student.getEmail(),email))
   {
       Optional<Student> studentOptional= studentRepository.findStudentByEmail(email);
       if (studentOptional.isPresent())
       {
           throw new IllegalStateException("email taken");
       }
       student.setEmail(email);
   }
 }

These are the students that i have in database基本上，我想更新id=1的学生的姓名和电子邮件。
That is postman header
And that is postman not showing any error after sending request