portlet - bookModeling 无法解决

Question

我的错误是：

"bookModeling" cannot be resolved

和我的 BookModeling：

public class BookModeling implements Serializable {
private static final long serialVersionUID = 2117669648358293028L;
private String Book;
public String getBook() {
return Book;
}
public void setBook(String book) {
Book = book;
}

我的 BookManageBean 类：

@ManagedBean(name = "bookManageBean")
@ViewScoped
public class BookManageBean implements Serializable {
private static final long serialVersionUID = 5646446743226853016L;
BookModeling bookModeling = new BookModeling();
}

我的 BookBackingBean 类：

@ManagedBean(name = "bookBackingBean")
@ViewScoped
public class BookBackingBean implements Serializable{
private static final long serialVersionUID = -552459151474443900L;
@ManagedProperty(value = "#{bookManageBean}")
private BookManageBean bookManageBean;
public BookManageBean getBookManageBean() {
    return bookManageBean;
}
public void setBookManageBean(BookManageBean bookManageBean) {
    this.bookManageBean = bookManageBean;
}

我遇到错误的地方：