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java - Student editing does not work (Java + Spring + MySQl)?

问题描述

I have a list of students. I want to do editing. Change the name, surname and avatar. I wrote the code, but it does not work, the data is not edited. You can see why it does not work for me. There is no error, it just does not change anything. After editing the name and surname and avatar do not change

Student Service

public interface StudentService {

    List<Student> getAllStudents();

    Student getStudentById(Long id);

    boolean saveStudent(Student student);

    boolean deleteStudentById(Long id);

    File loadAvatarByFileName(String filename);

    File saveAvatarImage(MultipartFile avatarImage) throws IOException;

        Student updateStudent(String name, String surname, MultipartFile avatar, Student targetStudent) throws IOException;
}

Student Service Impl

@Service
@Transactional
public class StudentServiceImpl implements StudentService {

    @Value("${storage.location}")

    private String storageLocation;

    private StudentRepository repository;

    public StudentServiceImpl() {

    }

    @Autowired
    public StudentServiceImpl(StudentRepository repository) {
        super();
        this.repository = repository;
    }

    @Override
    public List<Student> getAllStudents() {
        List<Student> list = new ArrayList<Student>();
        repository.findAll().forEach(e -> list.add(e));
        return list;
    }

    @Override
    public Student getStudentById(Long id) {
        Student student = repository.findById(id).get();
        return student;
    }

    @Override
    public boolean saveStudent(Student student) {
        try {
            repository.save(student);
            return true;
        } catch (Exception ex) {
            return false;
        }
    }

    @Override
    public boolean deleteStudentById(Long id) {
        try {
            repository.deleteById(id);
            return true;
        } catch (Exception ex) {
            return false;
        }

    }

    @Override

    public File loadAvatarByFileName(String filename) {

        return new File(storageLocation + "/" + filename);

    }

    @Override


    public File saveAvatarImage(MultipartFile avatarImage) throws IOException {

        File newFile = File.createTempFile(
                avatarImage.getName(),
                "." + avatarImage.getOriginalFilename().split("\\.")[1],

                new File(storageLocation));

        avatarImage.transferTo(newFile);

        return newFile;

    }

    @Override

    public Student updateStudent(String name, String surname, MultipartFile avatar, Student targetStudent)

           throws IOException {

        if (name != null && !name.equals(targetStudent.getName())) {

            targetStudent.setName(name);

        }

        if (surname != null && !surname.equals(targetStudent.getSurname())) {

            targetStudent.setSurname(surname);

        }

        String oldAvatarName = targetStudent.getAvatar();

        if (oldAvatarName != null) {
            Files.deleteIfExists(Paths.get(storageLocation + File.separator + oldAvatarName));
        }

        File newAvatar = null;
        if (avatar != null) {
            newAvatar = saveAvatarImage(avatar);
            assert newAvatar != null;
            targetStudent.setAvatar(newAvatar.getName());
        }

       boolean isSaved = saveStudent(targetStudent);

        if (!isSaved) {

            throw new IOException();

        }

        Files.deleteIfExists(Paths.get(storageLocation + File.separator + oldAvatarName));

        return targetStudent;

    }

Student Controller

package adil.java.schoolmaven.controller;

import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.servlet.ServletContext;
import adil.java.schoolmaven.entity.Student;
import adil.java.schoolmaven.service.StudentService;
import java.nio.file.FileSystemException;
import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.lang.NonNull;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class StudentController {

    @Autowired
    private ServletContext servletContext;

    // Constructor based Dependency Injection
    private StudentService studentService;

    public StudentController() {

    }

    @Autowired
    public StudentController(StudentService studentService) {
        this.studentService = studentService;
    }

    @RequestMapping(value = "/allStudents",  method = {RequestMethod.GET, RequestMethod.POST})

    public ModelAndView displayAllUser() {
        System.out.println("User Page Requested : All Students");
        ModelAndView mv = new ModelAndView();
        List<Student> studentList = studentService.getAllStudents();
        mv.addObject("studentList", studentList);
        mv.setViewName("allStudents");
        return mv;
    }



    @RequestMapping(value = "/addStudent", method = RequestMethod.GET)
    public ModelAndView displayNewUserForm() {
        ModelAndView mv = new ModelAndView("addStudent");
        mv.addObject("headerMessage", "Add Student Details");
        mv.addObject("student", new Student());
        return mv;
    }

    @PostMapping(value = "/addStudent")
    public String saveNewStudent(@RequestParam("name") @NonNull String name,
            @RequestParam("surname") @NonNull String surname,
            @RequestParam("avatar") MultipartFile file)
            throws IOException {

        Student student = new Student();
        student.setSurname(surname);
        student.setName(name);

        if (file != null && !file.isEmpty()) {
            student.setAvatar(studentService.saveAvatarImage(file).getName());
        }

        studentService.saveStudent(student);
        return "redirect:/allStudents";
    }

    @GetMapping(value = "/editStudent/{id}")
    public ModelAndView displayEditUserForm(@PathVariable Long id) {
        ModelAndView mv = new ModelAndView("editStudent");
        Student student = studentService.getStudentById(id);
        mv.addObject("headerMessage", "Редактирование студента");
        mv.addObject("student", student);
        return mv;
    }

    @PostMapping(value = "/editStudent")
    public String saveEditedUser(
            @RequestParam("id") Long id,
            @RequestParam("name") String name,
            @RequestParam("surname") String surname,
            @RequestParam("avatar") MultipartFile file) {

        try {

            studentService.updateStudent(name, surname, file, studentService.getStudentById(id));

        } catch (FileSystemException ex) {
            ex.printStackTrace();
        } catch (IOException e) {
            return "redirect:/error";
        }

        return "redirect:/allStudents";
    }

    @GetMapping(value = "/deleteStudent/{id}")
    public ModelAndView deleteUserById(@PathVariable Long id) {
        studentService.deleteStudentById(id);
        ModelAndView mv = new ModelAndView("redirect:/allStudents");

        return mv;

    }

}

Edit Student JSP

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <
        <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
        <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>

        <title>Home</title>
    </head>
    <body>

        <center>
                <h1>${headerMessage}</h1>


                <form:form method="POST" action="${pageContext.request.contextPath}/editStudent" enctype="multipart/form-data">
                    <table>
                        <input type="hidden" value="${student.id}" name="id"/>
                        <tr>

                            <td><label path="Name">Name</label></td>
                            <td><input type="text" name="name" value="${student.name}"/></td>
                        </tr>
                        <tr>
                            <td><label path="Surname">Surname</label></td>
                            <td><input name="surname" value="${student.surname}"/></td>
                        </tr>
                        <tr>
                            <td><label path="Avatar">Avatar:</label></td>
                            <td>
                                <img src="${pageContext.request.contextPath}/avatar?avatar=${student.avatar}"
                                     style="max-height: 200px; max-width: 200px;"/>
                            </td>
                            <td>
                                <input type="file" name="avatar"/>
                            </td>
                        </tr>
                        <tr>
                            <td><input class="btn btn-primary" type="submit" value="Save"></td>
                        </tr>
                    </table>
                </form:form>
        </center>
    </body>
</html>

My Log

(the error message translates to "The process cannot access the file because the file is being used by another process." according to google translate)

java.nio.file.FileSystemException: C:\Pictures\avatar3435295369309803118.jpg: Процесс не может получить доступ к файлу, так как этот файл занят другим процессом.

    at sun.nio.fs.WindowsException.translateToIOException(WindowsException.java:86)
    at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:97)
    at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:102)
    at sun.nio.fs.WindowsFileSystemProvider.implDelete(WindowsFileSystemProvider.java:269)
    at sun.nio.fs.AbstractFileSystemProvider.deleteIfExists(AbstractFileSystemProvider.java:108)
    at java.nio.file.Files.deleteIfExists(Files.java:1165)
    at adil.java.schoolmaven.service.StudentServiceImpl.updateStudent(StudentServiceImpl.java:122)
    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:498)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:338)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:197)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)
    at com.sun.proxy.$Proxy402.updateStudent(Unknown Source)
    at adil.java.schoolmaven.controller.StudentController.saveEditedUser(StudentController.java:98)
    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:498)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:870)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:776)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:881)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.sitemesh.webapp.contentfilter.ContentBufferingFilter.bufferAndPostProcess(ContentBufferingFilter.java:169)
    at org.sitemesh.webapp.contentfilter.ContentBufferingFilter.doFilter(ContentBufferingFilter.java:126)
Hibernate: 
    select

标签： javaspringjakarta-ee

解决方案

The error says that another process is using the file and therefore it cannot be deleted.

Do you have the given file open in another program?

Could it be that your code opens the file/keeps it open in another place while you are trying to delete it?

I see your StudentServiceImpl.updateStudent is calling Files.deleteIfExists(Paths.get(storageLocation + File.separator + oldAvatarName)); twice. According to the stack trace, the offending line is StudentServiceImpl.java:122. Which of the two lines is number 122 ?

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