1、分页显示中必须有两个参数，总记录数、记录列表，封装到PagerModel类中
PagerModel.java
1
package com.oa;
2
3import java.util.List;
4
5import com.oa.models.Organization;
6
7
/** *//**
8
*
9 * @author Administrator 分页模型，返回记录总数和相应记录
10
*/
11public class PagerModel 
{
12 private int total;
13 private List<Organization> list;
14
15
public int getTotal() {
16 return total;
17
}
18
19 public void setTotal(int total) {
20 this.total = total;
21 }
22
23 public List<Organization> getList() {
24 return list;
25 }
26
27 public void setList(List<Organization> list) {
28 this.list = list;
29 }
30}
2、显示页showorgs.jsp代码如下：
1<%@ page language="java" contentType="text/html; charset=GB18030"
2 pageEncoding="GB18030"%>
3<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
4<%@ taglib prefix="pg" uri="http://jsptags.com/tags/navigation/pager"%>
5<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
6<html>
7 <head>
8 <meta http-equiv="Content-Type" content="text/html; charset=GB18030">
9 <title>Insert title here</title>
10 </head>
11 <body>
12 <table>
13 <tr>
14 <td>
15 序号
16 </td>
17 <td>
18 机构名称
19 </td>
20 <td>
21 机构编号
22 </td>
23 <td>
24 父机构名称
25 </td>
26 <td>
27 相关操作
28 </td>
29 </tr>
30 <c:if test="${!empty pagerModel.list}">
31 <c:forEach items="${pagerModel.list}" var="org">
32 <tr>
33 <td>
34 ${org.orgid }
35 </td>
36 <td>
37 ${org.orgname }
38 </td>
39 <td>
40 ${org.orgsn }
41 </td>
42 <td>
43 ${org.parentorg.orgname }
44 </td>
45 <td>
46 <a href="#">删除</a>
47 </td>
48 </tr>
49 </c:forEach>
50 </c:if>
51 <c:if test="${empty pagerModel.list}">
52 <tr>
53 <td colspan="5">
54 没有找到相应的记录
55 </td>
56 </tr>
57 </c:if>
58 </table>
59 <pg:pager items="${pagerModel.total}" url="organization.action"
60 export="currentPageNumber=pageNumber" maxIndexPages="5"
61 maxPageItems="8">
62 <pg:param name="parentorgid" />
63 <pg:first>
64 <a href="${pageUrl }">首页</a>
65 </pg:first>
66 <pg:prev>
67 <a href="${pageUrl }">前一页</a>
68 </pg:prev>
69 <pg:pages>
70 <c:choose>
71 <c:when test="${currentPageNumber eq pageNumber}">
72 <font color="red">${pageNumber}</font>
73 </c:when>
74 <c:otherwise>
75 <a href="${pageUrl }">${pageNumber }</a>
76 </c:otherwise>
77 </c:choose>
78 </pg:pages>
79 <pg:next>
80 <a href="${pageUrl }">后一页</a>
81 </pg:next>
82 <pg:last>
83 <a href="${pageUrl }">尾页</a>
84 </pg:last>
85 </pg:pager>
86 </body>
87</html>
本页代码只对对应的记录做分页显示，并未对数据的操作做处理。
url：:分页的链接根地址，pager标签会在这个链接的基础上附加分页参数
items：总记录数，pager标签正是根据这个值来计算分页参数的
maxPageItems：每页显示的行数，默认为10
maxIndexPages：在循环输出页码的时候，最大输出多少个页码，默认是10
<pg:param>这个标签很有用，用来设置将要加入到URL的参数。使用Name属性指定即可。
<pg:prev> , <pg:pages>,<pg:next>这些标签都是导航标签顾名思义
3、Action的实现
OrganizationAction.java
1package com.oa.actions;
2
3import org.apache.struts2.ServletActionContext;
4
5import com.oa.PagerModel;
6import com.oa.managers.OrganizationManager;
7import com.opensymphony.xwork2.ActionSupport;
8
9@SuppressWarnings("serial")
10public class OrganizationAction extends ActionSupport {
11
12 private OrganizationManager organizationManager;
13
14 private int parentorgid;
15
16 private PagerModel pagerModel;
17
18 public int getParentorgid() {
19 return parentorgid;
20 }
21
22 public void setParentorgid(int parentorgid) {
23 this.parentorgid = parentorgid;
24 }
25
26 public void setOrganizationManager(OrganizationManager organizationManager) {
27 this.organizationManager = organizationManager;
28 }
29
30 public PagerModel getPagerModel() {
31 return pagerModel;
32 }
33
34 public void setPagerModel(PagerModel pagerModel) {
35 this.pagerModel = pagerModel;
36 }
37
38 @Override
39 public String execute() throws Exception {
40 /**//*
41 * int offset = 0;
42 *
43 * try { offset = Integer.parseInt(ServletActionContext.getRequest()
44 * .getParameter("pager.offset")); } catch (RuntimeException e) { //
45 * TODO Auto-generated catch block e.printStackTrace(); } int pagesize =
46 * 8;
47 */
48 System.out.println("parentorgid:"+parentorgid);
49 pagerModel = organizationManager.findOrgs(parentorgid);// ,
50 // offset,pagesize);
51 ServletActionContext.getRequest()
52 .setAttribute("pagerModel", pagerModel);
53 ServletActionContext.getRequest().setAttribute("parentorgid",
54 parentorgid);
55 return SUCCESS;
56 }
57
58}
AbstractorPagerManager.java
1package com.oa.managers.impl;
2
3import java.util.List;
4
5import org.hibernate.Query;
6import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
7
8import com.oa.PagerModel;
9import com.oa.SystemContext;
10import com.oa.models.Organization;
11
12public class AbstractorPagerManager extends HibernateDaoSupport {
13 @SuppressWarnings("unchecked")
14 public PagerModel searchPaginated(String hql) {
15 return this.searchPaginated(hql, null, SystemContext.getOffset(), SystemContext.getPagesize());
16 }
17 public PagerModel searchPaginated(String hql, Object obj) {
18 return this.searchPaginated(hql, new Object[] { obj }, SystemContext.getOffset(), SystemContext.getPagesize());
19 }
20 public PagerModel searchPaginated(String hql, Object[] params) {
21 return this.searchPaginated(hql, params, SystemContext.getOffset(), SystemContext.getPagesize());
22 }
23 public PagerModel searchPaginated(String hql, int offset, int pagesize) {
24 return this.searchPaginated(hql, null, offset, pagesize);
25 }
26
27 public PagerModel searchPaginated(String hql, Object obj, int offset,
28 int pagesize) {
29 return this
30 .searchPaginated(hql, new Object[] { obj }, offset, pagesize);
31 }
32
33 @SuppressWarnings("unchecked")
34 public PagerModel searchPaginated(String hql, Object[] params, int offset,
35 int pagesize) {
36 // 查询总的记录数
37 String countHql = this.getCountHql(hql);
38 Query query = this.getSession().createQuery(countHql);
39 if (query != null && params != null && params.length > 0) {
40 for (int i = 0; i < params.length; i++) {
41 query.setParameter(i, params[i]);
42 }
43 }
44 int total = ((Long) query.uniqueResult()).intValue();
45
46 // 查询机构列表
47
48 query = this.getSession().createQuery(hql);
49 if (query != null && params != null && params.length > 0) {
50 for (int i = 0; i < params.length; i++) {
51 query.setParameter(i, params[i]);
52 }
53 }
54 query.setFirstResult(offset);
55 query.setMaxResults(pagesize);
56 List<Organization> list = query.list();
57
58 PagerModel pagerModel = new PagerModel();
59 pagerModel.setTotal(total);
60 pagerModel.setList(list);
61 return pagerModel;
62
63 }
64
65 private String getCountHql(String hql) {
66 int index = hql.indexOf("from");
67 if (index != -1) {
68 return "select count(*) " + hql.substring(index);
69 }
70 throw new RuntimeException("不合法的HQL语句！");
71 }
72
73}
OrganizationManagerImpl.java
1package com.oa.managers.impl;
2
3import com.oa.PagerModel;
4import com.oa.managers.OrganizationManager;
5import com.oa.models.Organization;
6
7public class OrganizationManagerImpl extends AbstractorPagerManager implements
8 OrganizationManager {
9
10 public void addOrg(Organization org, int parentorgid) {
11
12 if (parentorgid != 0) {
13 org.setParentorg((Organization) this.getHibernateTemplate().load(
14 Organization.class, parentorgid));
15 }
16
17 this.getHibernateTemplate().save(org);
18
19 // TODO 设置Organization的唯一编号
20 org.setOrgsn(org.getParentorg() == null ? ("" + org.getOrgid()) : (org
21 .getParentorg().getOrgsn()
22 + "_" + org.getOrgid()));
23
24 this.getHibernateTemplate().update(org);
25 }
26
27 public void deleteOrg(int orgid) {
28 this.getHibernateTemplate().delete(
29 this.getHibernateTemplate().load(Organization.class, orgid));
30
31 }
32
33 public Organization findOrg(int orgid) {
34 return (Organization) this.getHibernateTemplate().load(
35 Organization.class, orgid);
36 }
37
38 public void modifyOrg(Organization org, int parentorgid) {
39 if (parentorgid != 0) {
40 org.setParentorg((Organization) this.getHibernateTemplate().load(
41 Organization.class, parentorgid));
42 }
43
44 this.getHibernateTemplate().update(org);
45 }
46
47 @SuppressWarnings("unchecked")
48 public PagerModel findOrgs(int parentorgid) {// , int offset, int
49 // pagesize) {
50 /**//*
51 * // 查询总的记录数 String selectCountHql = "select count(*) from Organization
52 * org where org.parentorg is null"; if (parentorgid != 0) {
53 * selectCountHql = "select count(*) from Organization org where
54 * org.parentorg.orgid=" + parentorgid; } int total = ((Long)
55 * this.getSession().createQuery(selectCountHql)
56 * .uniqueResult()).intValue(); // 查询机构列表 String selectHql = "from
57 * Organization org where org.parentorg is null"; if (parentorgid != 0) {
58 * selectHql = "from Organization org where org.parentorg.orgid=" +
59 * parentorgid; } List<Organization> list =
60 * this.getSession().createQuery(selectHql)
61 * .setFirstResult(offset).setMaxResults(pagesize).list(); PagerModel
62 * pagerModel = new PagerModel(); pagerModel.setTotal(total);
63 * pagerModel.setList(list); return pagerModel;
64 */
65
66 if (parentorgid == 0) {
67 /**//*
68 * return this.searchPaginated( "from Organization org where
69 * org.parentorg is null", offset, pagesize);
70 */
71 return this
72 .searchPaginated("from Organization org where org.parentorg is null");
73 }
74 /**//*
75 * return this.searchPaginated( "from Organization org where
76 * org.parentorg.orgid=?", parentorgid, offset, pagesize);
77 */
78
79 return this.searchPaginated(
80 "from Organization org where org.parentorg.orgid=?",
81 parentorgid);
82 }
83}
SystemContext.java
1package com.oa;
2
3public class SystemContext {
4 public static ThreadLocal<Integer> offset = new ThreadLocal<Integer>();
5 public static ThreadLocal<Integer> pagesize = new ThreadLocal<Integer>();
6
7 public static void setOffset(int offsetValue) {
8 offset.set(offsetValue);
9 }
10
11 public static int getOffset() {
12 Integer os = offset.get();
13 if (os == null) {
14 return 0;
15 }
16 return os;
17 }
18 public static void removeOffset(){
19 offset.remove();
20 }
21
22 public static void setPagesize(int pagesizeValue) {
23 pagesize.set(pagesizeValue);
24 }
25
26 public static int getPagesize() {
27 Integer ps = pagesize.get();
28 if (ps == null) {
29 return Integer.MAX_VALUE;
30 }
31 return ps;
32 }
33 public static void removePagesize(){
34 pagesize.remove();
35 }
36}
关于Action的配置比较简单，在此不再作介绍。
4、实现并配置过滤器
PagerFilter.java
1package com.oa.filters;
2
3import java.io.IOException;
4
5import javax.servlet.Filter;
6import javax.servlet.FilterChain;
7import javax.servlet.FilterConfig;
8import javax.servlet.ServletException;
9import javax.servlet.ServletRequest;
10import javax.servlet.ServletResponse;
11import javax.servlet.http.HttpServletRequest;
12
13import com.oa.SystemContext;
14
15public class PagerFilter implements Filter {
16
17 public void destroy() {
18
19 }
20
21 public void doFilter(ServletRequest request, ServletResponse response,
22 FilterChain chain) throws IOException, ServletException {
23
24 HttpServletRequest myrequest = (HttpServletRequest) request;
25 SystemContext.setOffset(this.getOffset(myrequest));
26 SystemContext.setPagesize(this.getPagesize());
27 try {
28 chain.doFilter(request, response);
29 } catch (Exception e) {
30
31 } finally {
32 SystemContext.removeOffset();
33 SystemContext.removePagesize();
34 }
35 }
36
37 protected int getOffset(HttpServletRequest request) {
38 int offset = 0;
39 try {
40 offset = Integer.parseInt(request.getParameter("pager.offset"));
41 } catch (NumberFormatException e) {
42 // TODO Auto-generated catch block
43 System.out.println("--------------------");
44 //e.printStackTrace();
45 }
46 return offset;
47 }
48
49 protected int getPagesize() {
50 return 8;
51 }
52
53 public void init(FilterConfig arg0) throws ServletException {
54
55 }
56
57}
在web.xml中配置过滤器，必须放在struts2之前，否则有可能不起作用
<filter>
<filter-name>pagerFilter</filter-name>
<filter-class>com.oa.filters.PagerFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>pagerFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>