Spring Mysql Hibernate

Hej mam problem bo połączyłam tabele komentarzy z tabela postów i dostaje błąd

Hibernate: 
    select
        post0_.postid as postid1_7_,
        post0_.autor as autor2_7_,
        post0_.opis as opis3_7_,
        post0_.tytul as tytul4_7_ 
    from
        post post0_ 
    where
        post0_.postid=?
Hibernate: 
    select
        comment0_.idComment as idCommen1_5_,
        comment0_.autor as autor2_5_,
        comment0_.opis as opis3_5_,
        comment0_1_.idComment as idCommen1_6_ 
    from
        comment comment0_ 
    left outer join
        comment_post comment0_1_ 
            on comment0_.idComment=comment0_1_.postid
kwi 16, 2018 1:48:54 PM org.springframework.web.servlet.tags.form.HiddenInputTag doStartTag
SEVERE: Invalid property 'idComment' of bean class [java.util.ArrayList]: Bean property 'idComment' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
org.springframework.beans.NotReadablePropertyException: Invalid property 'idComment' of bean class [java.util.ArrayList]: Bean property 'idComment' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

w kontrolerze mam:

@RequestMapping(value="/posts/{postid}/comments")
@Controller
public class CommentController {

@RequestMapping(value = "", method = RequestMethod.GET)
    public ModelAndView Comment(@PathVariable Long postid, ModelAndView model) {
		List<Post> list = postService.getAllPosts(postid);
        List<Comment> comment = commentService.getAllComment();
        model.addObject("comment", comment);
        model.addObject("list", list);
        model.setViewName("view");
        return model;
	
	}
	
	@RequestMapping(value = "/newComment", method = RequestMethod.GET)
    public ModelAndView newComment(@PathVariable Long postid, @ModelAttribute("comment")  Comment comment,
    		   BindingResult result){
		List<Post> list = postService.getAllPosts(postid);
		Map<String, Object> model = new HashMap<String, Object>();
        model.put("comment", commentService.getAllComment());
        model.put("list", list);
        return new ModelAndView("view", model);

    }
	
	@RequestMapping(value = "/saveComment", method = RequestMethod.POST)
	public ModelAndView saveComment(@PathVariable Long postid, @ModelAttribute Comment comment) {
		List<Post> list = postService.getAllPosts(postid);
		commentService.saveOrUpdate(comment);
	    return new ModelAndView("redirect:/posts/{postid}/comments");
	}

w .jsp

<div align="center">
        <form:form action="saveComment" method="post" commandName="comment">
        <form:hidden path="idComment"/>
        <div class="form-group row">
<div class="col-xs-4">
    <label for="ex3"></label>
    <input class="form-control" name="autor" id="ex3" type="string" placeholder="Autor">
  </div>
  </div>
  <div class="form-group row">
  <div class="col-xs-4">
    <label for="ex3"></label>
    <input class="form-control" name="opis" id="ex3" type="string" placeholder="Opis">
  </div>
</div>
<button type="submit" value="Save" class="btn btn-primary active">Dodaj</button>
        </form:form>
    </div>
    
<h2>${idComment}</h2>
<c:forEach var="post" items="${comment}">

<div class="container">
<div class="col-md-12">
    <h1>${comment.autor }</h1>
   

Bean property 'idComment' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

To powinno wszystko wyjaśnić. Po złączeniu tabel musisz również odwzorować to na modelach (tak działa ORM).

Pokaż kod klas encji, czyli Post i Comment.

@Entity
@Table(name = "comment")
public class Comment implements Serializable{

	private static final long serialVersionUID = 2984232256687388809L;
	
	@Id
    @GeneratedValue(strategy = GenerationType.AUTO)
	@Column
	private int idComment;
	
	@Column
	private String autor;
	
	@Column
	private String opis;
	
	@ManyToOne(fetch = FetchType.LAZY)
	@JoinTable(name="comment_post",
    joinColumns={@JoinColumn(name="postid")},
    inverseJoinColumns={@JoinColumn(name="idComment")})
	private Post post;

	public int getIdComment() {
		return idComment;
	}

	public void setIdComment(int idComment) {
		this.idComment = idComment;
	}

	public String getAutor() {
		return autor;
	}

	public void setAutor(String autor) {
		this.autor = autor;
	}

	public String getOpis() {
		return opis;
	}

	public void setOpis(String opis) {
		this.opis = opis;
	}

	public Post getPost() {
		return post;
	}

	public void setPost(Post post) {
		this.post = post;
	}
	
}

@Entity
@Table(name = "post")
public class Post implements Serializable{

	private static final long serialVersionUID = 8538629616831690171L;
	
	@Id
    @GeneratedValue(strategy = GenerationType.AUTO)
	@Column
	private Long postid;
	
	@Column
	private String autor;
	
	@Column
	private String tytul;
	
	@Column
	private String opis;
	
	/*private Blob image;*/
	
	/*@OneToMany
	@JoinColumn(name="idComment")
	private List<Comment> comment;*/
	
	public String getAutor() {
		return autor;
	}

	/*public Blob getImage() {
		return image;
	}

	public void setImage(Blob image) {
		this.image = image;
	}*/

	public Long getPostid() {
		return postid;
	}

	public void setPostid(Long postid) {
		this.postid = postid;
	}

	public void setAutor(String autor) {
		this.autor = autor;
	}

	public String getTytul() {
		return tytul;
	}

	public void setTytul(String tytul) {
		this.tytul = tytul;
	}

	public String getOpis() {
		return opis;
	}

	public void setOpis(String opis) {
		this.opis = opis;
	}
	
	/*public List<Comment> getComment() {
		return comment;
	}

	public void setComment(List<Comment> comment) {
		this.comment = comment;
	}*/
	
	
}

<h2>${idComment}</h2>

próbujesz wywołać attrybut którego nie podałaś w controllerze.

<c:forEach var="post" items="${comment}">
<div class="container">
<div class="col-md-12">
   <h1>${comment.autor }</h1>

zamiast ${comment.autor } powinno być ${post.autor}

EDIT:

<form:hidden path="idComment"/>

Nie musisz przekazywać id, usuń tą linię i daj znać czy dalej występuje ten błąd.

Czy mogłabym prosić o to żeby ktoś spojrzał na to co zrobiłam bo nie moge sobie poradzić z wyświetleniem komentarzy odpowiadających postid?

PostController

@RequestMapping(value = "/{postid}", method = RequestMethod.GET)
    public ModelAndView findid(@PathVariable Long postid, ModelAndView model, Post post){
		List<Post> list = postService.getAllPosts(postid);
		List<Comment> comments = postService.get(postid).getComments();
        model.addObject("list", list);
        model.addObject("comments", comments);
        model.setViewName("view");
        return model;
    }

Post

@OneToMany(cascade = CascadeType.ALL, 
	        mappedBy = "post", orphanRemoval = true)
	@org.hibernate.annotations.LazyCollection(org.hibernate.annotations.LazyCollectionOption.EXTRA)
	/*@JoinColumn(name="idComment")*/
	private List<Comment> comments = new ArrayList<>();

public List<Comment> getComments() {
		return comments;
	}

	public void setComments(List<Comment> comments) {
		this.comments = comments;
	}

Powinnaś się odwołać do metody getComments() dla danego obiektu klasy Post.

Skoro masz PathVariable, aby uzyskać dostęp do postu z odpowiednim id, dlaczego przekazujesz do widoku listę wszystkich postów? powinno to wyglądać mniej więcej tak:

@RequestMapping(value = "/{postid}", method = RequestMethod.GET)
   public ModelAndView findid(@PathVariable Long postid, ModelAndView model, Post post){
       Post post = postService.gePost(postid);
       List<Comment> comments = post.getComments();
       model.addObject("post", post);
       model.addObject("comments", comments);
       model.setViewName("view");
       return model;
   }

Dzięki byłam blisko, pomogłeś mi ... :) Liste postów wyświetlam po id posta ponieważ chce żeby użytkownik widział pod jakim postem dodaje komentarz.. Teraz mam jeszcze jeden problem a natomiast chciałabym żebyś po raz ostatni wyjaśnił mi jedną rzecz... Czy ja aby na pewno dobrze połączyłam swoje tabele post i comment? Bo dostaje błąd a że to mój pierwszy projekt w tym frameworku to pewne rzeczy są jeszcze dla mnie nie jasne...

@ManyToOne(fetch = FetchType.LAZY)
	@JoinColumn(name="postid", nullable = false, insertable = false, updatable = false)
	private Post post;

@OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
	@JoinTable(name="comment_post",
    joinColumns={@JoinColumn(name="postid")},
    inverseJoinColumns={@JoinColumn(name="idComment")})
	private List<Comment> comments = new ArrayList<>();

CREATE TABLE `post` (
  `postid` int(11) NOT NULL AUTO_INCREMENT,
  `autor` varchar(45) NOT NULL,
  `tytul` varchar(512) NOT NULL,
  `opis` varchar(5000) NOT NULL,
  PRIMARY KEY (`postid`)
);

CREATE TABLE `comment` (
  `idComment` int(11) NOT NULL AUTO_INCREMENT,
  `autor` varchar(45) NOT NULL,
  `opis` varchar(1000) NOT NULL,
  `postid` int(11) NOT NULL,
  PRIMARY KEY (`idComment`),
  KEY `fk_post` (`postid`),
  CONSTRAINT `fk_post` FOREIGN KEY (`postid`) REFERENCES `post` (`postid`)
);

CREATE TABLE comment_post (
    postid int(11) NOT NULL,
    idComment int(11) NOT NULL,
    PRIMARY KEY (postid),
    CONSTRAINT FK_comment FOREIGN KEY (idComment) REFERENCES comment (idComment)
);

Błąd który otrzymuje to brak pola postid ale przecież on powinien być wstawiany automatycznie czy nie?? :

Hibernate: 
    select
        comments0_.postid as postid1_7_0_,
        comments0_.idComment as idCommen2_6_0_,
        comment1_.idComment as idCommen1_5_1_,
        comment1_.autor as autor2_5_1_,
        comment1_.opis as opis3_5_1_,
        comment1_.postid as postid4_5_1_,
        post2_.postid as postid1_7_2_,
        post2_.autor as autor2_7_2_,
        post2_.opis as opis3_7_2_,
        post2_.tytul as tytul4_7_2_ 
    from
        comment_post comments0_ 
    inner join
        comment comment1_ 
            on comments0_.idComment=comment1_.idComment 
    inner join
        post post2_ 
            on comment1_.postid=post2_.postid 
    where
        comments0_.postid=?
Hibernate: 
    select
        post0_.postid as postid1_7_0_,
        post0_.autor as autor2_7_0_,
        post0_.opis as opis3_7_0_,
        post0_.tytul as tytul4_7_0_,
        comments1_.postid as postid1_7_1_,
        comment2_.idComment as idCommen2_6_1_,
        comment2_.idComment as idCommen1_5_2_,
        comment2_.autor as autor2_5_2_,
        comment2_.opis as opis3_5_2_,
        comment2_.postid as postid4_5_2_,
        post3_.postid as postid1_7_3_,
        post3_.autor as autor2_7_3_,
        post3_.opis as opis3_7_3_,
        post3_.tytul as tytul4_7_3_ 
    from
        post post0_ 
    left outer join
        comment_post comments1_ 
            on post0_.postid=comments1_.postid 
    left outer join
        comment comment2_ 
            on comments1_.idComment=comment2_.idComment 
    left outer join
        post post3_ 
            on comment2_.postid=post3_.postid 
    where
        post0_.postid=?
Hibernate: 
    insert 
    into
        comment
        (autor, opis) 
    values
        (?, ?)
19:20:55.355 [http-bio-8088-exec-4] WARN  o.h.e.jdbc.spi.SqlExceptionHelper - SQL Error: 1364, SQLState: HY000
19:20:55.356 [http-bio-8088-exec-4] ERROR o.h.e.jdbc.spi.SqlExceptionHelper - Field 'postid' doesn't have a default value
19:20:55.358 [http-bio-8088-exec-4] WARN  o.h.e.jdbc.spi.SqlExceptionHelper - SQL Warning Code: 1364, SQLState: HY000
19:20:55.358 [http-bio-8088-exec-4] WARN  o.h.e.jdbc.spi.SqlExceptionHelper - Field 'postid' doesn't have a default value

masz tu klasyczny związek jeden-do-wielu, trochę przekombinowałaś z mapowaniem - zobacz jak dokładnie powinnaś to zrobić:
https://vladmihalcea.com/the-best-way-to-map-a-onetomany-association-with-jpa-and-hibernate/