我有1类和1个bean：Book.java和BookCatelogBean.java. Book类有3个属性：id,title和author,它们是相应的getter和setter. BookCatelogBean包含一个ArrayList< Book>在那里我用书籍填充(以后我会把它连接到一个数据库).
我有两个页面：index.xhtml和book.xhtml.我想在index.xhtml上显示每个格式为REST链接的图书标题列表,并将其ID设置为book.xhtml,如下所示：< h：link outcome =“book？id =#{bookCatelogBean.id}”值=“#{bookCatelogBean.title}”/>
我知道如何使用BookCatelogBean来显示1本书,但是我想显示所有的书？我有一个想法,调用一个名为getAllBooks()的BookCatelogBean的方法,该方法返回每个图书标题,但是如何将它们中的每一个作为JavaserverFace链接而不是字符串返回index.xhtml？
谢谢
这是我的代码：
Book.java
package bookshop;
import java.io.Serializable;
public class Book implements Serializable {
private int id;
private String title;
private String author;
public Book(int id,String title,String author){
this.title = title;
this.id = id;
this.author = author;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
}
BookCatelogBean.java
package bookshop;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
@ManagedBean
@SessionScoped
public class BookCatelogBean implements Serializable {
private int currentItem = 0;
private ArrayList<Book> books = new ArrayList<Book>(Arrays.asList(
new Book(1,"Theory of Money and Credit","Ludwig von Mises"),new Book(2,"Man,Economy and State","Murry Rothbard"),new Book(3,"Real Time Relationships","Stefan Molyneux")));
public String getTitle(){
return books.get(currentItem).getTitle();
}
public int getId(){
return books.get(currentItem).getId();
}
public String getAuthor(){
return books.get(currentItem).getAuthor();
}
}
的index.xhtml
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html">
<h:head>
<title>BookShop</title>
</h:head>
<h:body>
<h:link outcome="book?id=#{bookCatelogBean.id}" value="#{bookCatelogBean.title}" />
</h:body>
</html>
解决方法
<ui:repeat>和
<h:dataTable>.前者对响应没有任何影响(因此您可以对最终的HTML输出进行100％的控制),而后者呈现HTML< table>响应并且要求
<h:column>表示< td>的列.两个组件都可以包含列表E.作为价值.
所以,你可以让你的托管bean如下：
@ManagedBean
@RequestScoped
public class BookCatalog implements Serializable {
private List<Book> books;
@PostConstruct
public void init() {
books = new ArrayList<Book>();
books.add(new Book(1,"Ludwig von Mises"));
books.add(new Book(2,"Murry Rothbard"));
books.add(new Book(3,"Stefan Molyneux"));
}
public List<Book> getBooks() {
return books;
}
}
你也可以使用< ui：repeat>以生成例如< ul>< li> ;:::
<ul>
<ui:repeat value="#{bookCatalog.books}" var="book">
<li>
<h:link value="#{book.title}" outcome="book">
<f:param name="id" value="#{book.id}" />
</h:link>
</li>
</ui:repeat>
</ul>
(注意,var属性基本上暴露了当前迭代的项目,恰好在组件中EL范围内的给定名称)
以下是使用< h：dataTable>代替：
<h:dataTable value="#{bookCatalog.books}" var="book">
<h:column>
<h:link value="#{book.title}" outcome="book">
<f:param name="id" value="#{book.id}" />
</h:link>
</h:column>
</h:dataTable>
对于JSTL< c：forEach>,这也是很可能的,但是您应该记住,JSTL标签的生命周期与JSF组件不同.长篇小说：JSTL in JSF2 Facelets… makes sense?
也可以看看：
> How to choose the right bean scope?
> When should I load the collection from database for h:dataTable
> Creating master-detail pages for entities,how to link them and which bean scope to choose
