JSP's iterating using jstl

Question

In this code I get authorId for each author's name from bookListArray and show it for each book, using iterating element aBook. How can I refactor my code with no scriplets? How can I iterate my bookListArray in .java code?

<liferay-ui:search-container>
<liferay-ui:search-container-results results="${bookListArray}" />
<liferay-ui:search-container-row className="builder.model.Book" keyProperty="bookId" modelVar="aBook">
    <liferay-ui:search-container-column-text property="bookName" name="book-Name" />
    <liferay-ui:search-container-column-text property="bookDescription" name="description" />
   <% 
     Author bookAuthor = AuthorLocalServiceUtil.getAuthor(aBook.getAuthorId());        
   %>
    <liferay-ui:search-container-column-text value="<%=bookAuthor.getAuthorName() %>" name="Author" />
    <liferay-ui:search-container-column-jsp path="/html/actionBook.jsp" align="right" />
</liferay-ui:search-container-row>
<liferay-ui:search-iterator />

It's my author and book lists:

List<Book> bookList = BookLocalServiceUtil.getBooks(QueryUtil.ALL_POS, QueryUtil.ALL_POS);
List<Author> authorList = AuthorLocalServiceUtil.getAuthors(QueryUtil.ALL_POS, QueryUtil.ALL_POS);

request.setAttribute("bookListArray", bookList);
request.setAttribute("authorListArray", authorList);

if you want to look at my project you can do it here: https://github.com/AlBoldyrev/Library/blob/master/bundles/tomcat-7.0.62/webapps/LibraryBook-portlet/WEB-INF/src/com/softwerke/BookAndAuthor.java

@Parkash I need your help! :P – Al.Boldyrev Sep 13 '16 at 18:26 — Al.Boldyrev, Sep 13 '16 at 18:26
Where is bookListArray, may include that code too – Bibek Shakya Sep 13 '16 at 18:28 — Bibek Shakya, Sep 13 '16 at 18:28
@B'bekShakya I've updated my question – Al.Boldyrev Sep 13 '16 at 19:18 — Al.Boldyrev, Sep 13 '16 at 19:18

score 0 · Accepted Answer · answered Sep 26 '16 at 12:26

The answer was not so easy. First of all, in my situation, I can only show data from database tables. Therefore, to solve this problem, we should create 2 new model classes to hold there important variables.

I understand, that it wasn't one-string-question, but Im a bit dissapointed that no one gives even any ideas, because for professional it is very easy.

So:

We should create new classes AuthorModel and BookModel (I'll omit all package and import info):

public class AuthorModel {
private Author author;
private int count;

public AuthorModel(Author author) {
    this.author = author;
    this.count = BookLocalServiceUtil.countByAuthor(author.getAuthorId());
}

public String getAuthorName() {
    return author.getAuthorName();
}  

public long getAuthorId() {
     return author.getAuthorId();
}

public int getCount() {
     return count;
}
}

--

public class BookModel {

private Book book;
private Author author;
private long authorId;

public BookModel(Book book) {
    this.book = book;
}

public String getBookName() {
    return book.getBookName();
}

public String getBookDescription() {
    return book.getBookDescription();
}

public String getAuthorName() throws PortalException, SystemException {
    this.authorId = book.getAuthorId();
    author = AuthorLocalServiceUtil.getAuthor(authorId);
    String authorName = author.getAuthorName();
    return authorName;
}

public long getBookId() {
    return book.getBookId();
}
}

After that, we should use this classes in our portlet class:

List<BookModel> bookModelList = ArrayUtil.getAllBooks();
List<AuthorModel> authorModelList = ArrayUtil.getAllAuthors();
request.setAttribute("bookModels", bookModelList);
request.setAttribute("authorModels", authorModelList);

And our getAllBooks()/getAllAuthors() methods:

public class ArrayUtil {

protected static List<AuthorModel> getAllAuthors() throws SystemException{
    List<AuthorModel> authors = new ArrayList<AuthorModel>();
    List<Author> authorList = AuthorLocalServiceUtil.getAuthors(QueryUtil.ALL_POS, QueryUtil.ALL_POS);
    for (Author author : authorList) {
        authors.add(new AuthorModel(author));
    }
    return authors;
}

protected static List<BookModel> getAllBooks() throws SystemException{
    List<BookModel> books = new ArrayList<BookModel>();
    List<Book> bookList = BookLocalServiceUtil.getBooks(QueryUtil.ALL_POS, QueryUtil.ALL_POS);
    for (Book book: bookList) {
        books.add(new BookModel(book));
    }
    return books;
}
}

score 0 · Answer 2 · answered Oct 04 '16 at 12:59

The best approach for to this is to retrieve the list in your controller and add it to the request as attributes. Then you can iterate it with c:foreach:

Example:

Controller:

List<Author> authorList = AuthorLocalServiceUtil.getAuthors(QueryUtil.ALL_POS, QueryUtil.ALL_POS);
request.setAttribute("authorModels", authorList);

JSP:

<c:foreach items="${authorList}" var="author">
     <c:out value="${author.attr1}"/>
     <c:out value="${author.attr2}"/>
</c:foreach>

Then you have to include something like this into your SearchContainer.

JSP's iterating using jstl

2 Answers2