Question

@RequestMapping(value = "/post/{id}/comment")
public String comment(@PathVariable("id") Long id, @ModelAttribute("comment") Comment comment, Model model) throws Exception {

    Authentication auth = SecurityContextHolder.getContext().getAuthentication();
    Post post = postSrv.findById(id);

    if (auth != null) {
        String email = auth.getName();
        User currentUser = userService.findByEmail(email);            

        if (comment.getContent() != "") {
            comment.setAuthor(currentUser);
            post.getCommentList().add(comment);
            comSrv.create(comment);
        }
    }
    return "redirect:/post/{id}/";
}

堆栈跟踪：

Hibernate: insert into comments (author_id, content, date) values (?, 
?, ?)
Hibernate: insert into posts_comments (post_id, comment_id) values (?, 
?)
2017-10-12 18:59:22.521  WARN 7714 --- [nio-8080-exec-6] 
o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 1452, SQLState: 
23000
2017-10-12 18:59:22.521 ERROR 7714 --- [nio-8080-exec-6] 
o.h.engine.jdbc.spi.SqlExceptionHelper   : Cannot add or update a 
child row: a foreign key constraint fails (`blog_db`.`posts_comments`, 
CONSTRAINT `FKaaxivndylqts0ji75et8xo557` FOREIGN KEY (`comment_id`) 
REFERENCES `comments` (`id`))
2017-10-12 18:59:22.524  INFO 7714 --- [nio-8080-exec-6] 
o.h.e.j.b.internal.AbstractBatchImpl     : HHH000010: On release of 
batch it still contained JDBC statements
2017-10-12 18:59:22.535 ERROR 7714 --- [nio-8080-exec-6] o.a.c.c.C.[.
[.[/].[dispatcherServlet]    : Servlet.service() for servlet 
[dispatcherServlet] in context with path [] threw exception [Request 
processing failed; nested exception is 
org.springframework.dao.DataIntegrityViolationException: could not 
execute statement; SQL [n/a]; constraint [null]; nested exception is 
org.hibernate.exception.ConstraintViolationException: could not 
execute statement] with root cause  
com.mysql.jdbc.exceptions.jdbc4.
MySQLIntegrityConstraintViolationException: Cannot add or update a 
child row: a foreign key constraint fails (`blog_db`.`posts_comments`, 
CONSTRAINT `FKaaxivndylqts0ji75et8xo557` FOREIGN KEY (`comment_id`) 
REFERENCES `comments` (`id`))

commentList：

@OneToMany
@JoinTable(name = "posts_comments", joinColumns = @JoinColumn(name = 
"post_id"),
inverseJoinColumns = @JoinColumn(name = "comment_id"))
private List<Comment> commentList;

整个项目： https://github.com/ashofthephoenix/Blog/tree/master/src/main/java/com/paulthemenace/blog

有谁知道如何解决这个问题？我在保持＆＃39; comment＆＃39;之后尝试添加到commentList，但它没有将值插入posts_comments表。删除外键不会更新comment_id值..

谢谢！

Spring Boot，Hibernate和MySQL - 无法添加或更新子行

0 个答案: