wicket之实现IDataProvider接口，只查询当前页数据

左手的ㄟ右手 2022-08-01 01:18 42阅读 0赞

1.html文件

Html代码   ![收藏代码][icon_star.png]

1.  <html>  
2.    <head>  
3.      <link href="styles/wicket.css" rel="stylesheet" type="text/css">  
4.      <link href="styles/office.css" rel="stylesheet" type="text/css">  
5.    </head>  
6.  <body>  
7.      <h3>DataView+ListDataProvider例子</h3>  
8.      <form wicket:id ="form">  
9.          <span wicket:id ="navigator">这里显示分页操作</span>  
10.         <table width="100%" border="0" cellspacing="1" cellpadding="0" id="baseCodeSetting">  
11.           <thead>   
12.             <tr>  
13.                 <th align="center">姓名</th>  
14.                 <th align="center" width="50">性别</th>  
15.                 <th align="center">职务</th>  
16.                 <th align="center">联系电话</th>  
17.                 <th align="center">QQ</th>  
18.                 <th align="center">E-mail</th>  
19.                 <th align="center">博客地址</th>  
20.                 <th align="center" width="50">操作</th>  
21.             </tr>  
22.           </thead>  
23.           <tbody>  
24.             <tr wicket:id="cards">  
25.                 <td align="center" wicket:id ="name">title </td>  
26.                 <td align="center" wicket:id ="sex">author</td>  
27.                 <td align="center" wicket:id ="duty">duty</td>  
28.                 <td align="center" wicket:id ="tel">tel</td>  
29.                 <td align="center" wicket:id ="qq">qq</td>  
30.                 <td align="center" wicket:id ="e\_mail">e\_mail</td>  
31.                 <td align="center"><a wicket:id ="blog">blog</a></td>  
32.                 <td align="center"><a wicket:id="edit">edit</a></td>  
33.             </tr>  
34.           </tbody>  
35.         </table >  
36.     </form>  
37. </body>  
38. </html>

2.java文件

Java代码   ![收藏代码][icon_star.png]

1.  package com.logcd.wicket.cards;  
2.    
3.  import java.io.Serializable;  
4.  import java.util.ArrayList;  
5.  import java.util.Collections;  
6.  import java.util.Iterator;  
7.  import java.util.List;  
8.    
9.  import org.apache.wicket.markup.html.WebPage;  
10. import org.apache.wicket.markup.html.basic.Label;  
11. import org.apache.wicket.markup.html.form.Form;  
12. import org.apache.wicket.markup.html.link.ExternalLink;  
13. import org.apache.wicket.markup.html.link.Link;  
14. import org.apache.wicket.markup.html.navigation.paging.PagingNavigator;  
15. import org.apache.wicket.markup.repeater.Item;  
16. import org.apache.wicket.markup.repeater.data.DataView;  
17. import org.apache.wicket.markup.repeater.data.IDataProvider;  
18. import org.apache.wicket.model.IModel;  
19. import org.apache.wicket.model.Model;  
20. import org.apache.wicket.spring.injection.annot.SpringBean;  
21.   
22. import com.logcd.web.bo.KingCards;  
23. import com.logcd.web.bo.dao.KingCardsDao;  
24.   
25. @SuppressWarnings(\{ "unchecked", "serial" \})  
26. public class DataViewPage extends WebPage\{  
27.       
28.     @SpringBean(name = "kingCardsDao")  
29.     private KingCardsDao kingCardsDao;  
30.   
31.     public DataViewPage() \{  
32.         super();  
33.         final DataView listView = new DataView("cards", new KingCardsDataProvider(), 2) \{  
34.             protected void populateItem(Item item) \{  
35.                 final KingCards card = (KingCards) item.getModelObject();  
36.                 item.add(new Label("name", card.getName()));  
37.                 item.add(new Label("sex", card.getSex()));  
38.                 item.add(new Label("duty", card.getDuty()));  
39.                 item.add(new Label("tel", card.getTel()));  
40.                 item.add(new Label("e\_mail", card.getEMail()));  
41.                 item.add(new Label("qq", card.getQq()));  
42.                 item.add(new ExternalLink("blog", card.getBlog(),card.getBlog()));  
43.                 item.add(new Link("edit") \{  
44.                     public void onClick() \{  
45.                     \}  
46.                 \});  
47.             \}  
48.         \};  
49.         Form form = new Form("form") \{  
50.             protected void onSubmit() \{  
51.             \}  
52.         \};  
53.         this.add(form);  
54.         form.add(listView);  
55.         form.add(new PagingNavigator("navigator", listView));  
56.     \}  
57.       
58.     /\*\* 
59.      \* 提供分页数据的内部类 
60.      \* @author logcd 
61.      \*/  
62.     public class KingCardsDataProvider implements IDataProvider\{  
63.         private static final long serialVersionUID = 1L;  
64.         private List list = Collections.synchronizedList(new ArrayList());  
65.           
66.         public Iterator iterator(int firstItem, int itemsPerPage) \{  
67.             Integer pageNo=firstItem/itemsPerPage;//查询第几页  
68.             StringBuilder hql = new StringBuilder();  
69.             hql.append("from KingCards cards where cards.Type=0");  
70.             list=kingCardsDao.findOnePageObjects(hql.toString(), pageNo, itemsPerPage);  
71.             return list.iterator();  
72.         \}  
73.   
74.         public IModel model(Object obj) \{  
75.             return new Model((Serializable) obj);  
76.         \}  
77.   
78.         public int size() \{  
79.             return kingCardsDao.findRowCount("select count(\*) from KingCards cards where cards.Type=0");  
80.         \}  
81.   
82.         public void detach() \{  
83.              this.list.clear();  
84.         \}  
85.     \}  
86. \}

3.dao中的两个方法

Java代码   ![收藏代码][icon_star.png]

1.  /\*\* 
2.   \* 根据Hql,返回结果集中的一页 
3.   \* @param hql 
4.   \* @param pageNo         第几页 
5.   \* @param itemsPerPage   每页记录条数 
6.   \* @return 
7.   \*/  
8.  @SuppressWarnings("unchecked")  
9.  public List<T> findOnePageObjects(final String hql,final Integer pageNo,final Integer itemsPerPage)\{  
10.     return getHibernateTemplate().executeFind(new HibernateCallback() \{  
11.         public Object doInHibernate(Session session) throws HibernateException, SQLException \{  
12.             return session.createQuery(hql).setFirstResult(pageNo\*itemsPerPage).setMaxResults(itemsPerPage).list();  
13.         \}  
14.     \});  
15. \}  
16. /\*\* 
17.  \* 根据自己的制定的hql来查询返回的所有记录的总数 
18.  \*  
19.  \* @param hql 
20.  \* @return 
21.  \*/  
22. public int findRowCount(final String hql) \{  
23.     return ((Long) getHibernateTemplate().execute(new HibernateCallback() \{  
24.         public Object doInHibernate(Session session) throws HibernateException, SQLException \{  
25.             return session.createQuery(hql).iterate().next();  
26.         \}  
27.   
28.     \})).intValue();  
29. \}

转自: http://log-cd.iteye.com/blog/336472

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