Struts2 中循环迭代的使用示例.

以下为Struts2 中循环迭代的使用示例. 在我写的demo中我用了3重迭代，虽然有些麻烦，目的是为了显示迭代的逻辑性和可读性。

用户User -----1：N ----- 书本Book 

书本Book -----1：N ----- 出版商 Publisher （就是多个出版商出奔这本书）

以下为测试源码和截图效果：

testIterator.jsp

<%@ page contentType="text/html; charset=GBK" language="java"%>
<%@taglib prefix="s" uri="/struts-tags"%>

<%            class User
            {
                private String userName;

                private String passWord;
                
                private java.util.List bookList;

                public String getPassWord()
                {
                    return passWord;
                }

                public void setPassWord(String passWord)
                {
                    this.passWord = passWord;
                }

                public String getUserName()
                {
                    return userName;
                }

                public void setUserName(String userName)
                {
                    this.userName = userName;
                }
                
                public java.util.List getBookList()
                {
                    return bookList;
                }

                public void setBookList(java.util.List bookList)
                {
                    this.bookList = bookList;
                }

            }

            class Book
            {
                private String bookName;
                private String price;
                private java.util.List publisherList;

                public String getBookName()
                {
                    return bookName;
                }

                public void setBookName(String bookName)
                {
                    this.bookName = bookName;
                }
                public String getPrice()
                {
                    return price;
                }

                public void setPrice(String price)
                {
                    this.price = price;
                }
                
                public java.util.List getPublisherList()
                {
                    return publisherList;
                }

                public void setPublisherList(java.util.List publisherList)
                {
                    this.publisherList = publisherList;
                }
            }
            
            class Publisher
            {
                private String publisherName;

                public String getPublisherName()
                {
                    return publisherName;
                }

                public void setPublisherName(String publisherName)
                {
                    this.publisherName = publisherName;
                }
            }
%>

<%
    java.util.List userList = new java.util.ArrayList(); 
    java.util.List bookList = new java.util.ArrayList(); 
    java.util.List publisherList = new java.util.ArrayList(); 
    
    Publisher publisher = new Publisher();
    publisher.setPublisherName("华中师大");
    publisherList.add(publisher);
    publisher = new Publisher();
    publisher.setPublisherName("中国大学");
    publisherList.add(publisher);
    
    Book book = new Book();
    book.setBookName("Math");
    book.setPrice("50");
    book.setPublisherList(publisherList);
    bookList.add(book);
    book = new Book();
    book.setBookName("Sicence");
    book.setPrice("100");
    book.setPublisherList(publisherList);
    bookList.add(book);
    bookList.add(book);
    
    User u = new User();
    u.setUserName("Jack");
    u.setPassWord("66666");
    u.setBookList(bookList);
    userList.add(u);
    
    u = new User();
    u.setUserName("Tom");
    u.setPassWord("55555");
    u.setBookList(bookList);
    userList.add(u);
    
    u = new User();
    u.setUserName("Shawn");
    u.setPassWord("00000");
    u.setBookList(bookList);
    userList.add(u);
    
    request.setAttribute("users", userList);
    
%>

<table border="1" width="400" border="1">
    <tr>
        <th>姓名</th>
        <th>密码</th>
        <th>书籍</th>
        <th>&nbsp;</th>
    </tr>
    <s:iterator value="#request.users" id="usersResult" status="st">
        <tr <s:if test="#st.odd">style="background-color:#bbbbbb"</s:if>>
            <td><s:property value="userName" /></td>
            <td><s:property value="passWord" /></td>
            <td>
                <table  align="center" border="1" width="100%">
                <tr bgcolor="red">
                    <th>书名</th>
                    <th>价格</th>
                    <th>出版社</th>
                </tr>
                <s:iterator value="bookList" id="bookName" status="st">
                        <tr>
                            <TD><s:property value="bookName"/></TD>
                            <TD><s:property value="price"/></TD>
                            <td>
                                <table  align="center" border="1">
                                <s:iterator value="publisherList" id="publisher" status="st">
                                        <tr>
                                            <TD><s:property value="publisherName"/></TD>
                                        </tr>
                                </s:iterator>
                                </table>
                            </td>
                            
                            
                        </tr>
                </s:iterator>
                </table>
            </td>
            <TD>
                <s:if test="#st.first">是首元素</s:if>
                <s:elseif test="#st.last">是末元素</s:elseif>
                <s:else>是非首末元素</s:else>
            </TD>
        </tr>
    </s:iterator>
    
    <hr>
    
    <tr></tr>
    <tr></tr>
    <tr></tr>
    <tr></tr>
    <s:iterator value="#request.users" id="usersResult" status="st">
        <tr <s:if test="#st.odd">style="background-color:#bbbbbb"</s:if>>
            <td><s:property value="userName" /></td>
            <td><s:property value="passWord" /></td>
            <td>
                <table  align="center">
                
                    <s:set value="#usersResult" name="ppp"/>
                    <!--s:property value="#ppp.bookList"/ -->                          <!-- 写法与上面的不同A -->
                    
                    <s:iterator value="#ppp.bookList" id="bookName" status="st">
                        <s:set value="#bookName" name="userIndex"/>
                        <tr>
                            <TD><s:property value="#userIndex.bookName"/></TD>        <!-- 写法与上面的不同B -->
                            <TD><s:property value="#userIndex.price"/></TD>
                            <TD>
                                <s:if test="#st.first">首元素</s:if>
                                <s:elseif test="#st.last">末元素</s:elseif>
                                <s:else>中间元素</s:else>
                            </TD>
                        </tr>
                    </s:iterator>
                    
                    
                </table>
            </td>
            <TD>
                <s:if test="#st.first">是首元素</s:if>
                <s:elseif test="#st.last">是末元素</s:elseif>
                <s:else>是非首末元素</s:else>
            </TD>
        </tr>
    </s:iterator>
    
    
</table>

 

效果图：

姓名	密码	书籍
Jack	66666	书名 价格 出版社 Math 50 华中师大 中国大学 Sicence 100 华中师大 中国大学 Sicence 100 华中师大 中国大学	是首元素
Tom	55555	书名 价格 出版社 Math 50 华中师大 中国大学 Sicence 100 华中师大 中国大学 Sicence 100 华中师大 中国大学	是非首末元素
Shawn	00000	书名 价格 出版社 Math 50 华中师大 中国大学 Sicence 100 华中师大 中国大学 Sicence 100 华中师大 中国大学	是末元素
Jack	66666	Math 50 首元素 Sicence 100 中间元素 Sicence 100 末元素	是首元素
Tom	55555	Math 50 首元素 Sicence 100 中间元素 Sicence 100 末元素	是非首末元素
Shawn	00000	Math 50 首元素 Sicence 100 中间元素 Sicence 100 末元素	是末元素