分页处理的bean类PageableResultSet.java的构造函数参数为一个ResultSet对象，即执行查询语句得到的ResultSet。其具体代码如下：
public class PageableResultSet extends ResultSet{
protected java.sql.ResultSet rs = null;
protected int rowsCount;
protected int pageSize;
protected int curPage;
protected String command = "";
public PageableResultSet(java.sql.ResultSet rs)
throws java.sql.SQLException {
if (rs == null)
throw new SQLException("given ResultSet is NULL", "user");
rs.last();//将指针移动到此 ResultSet 对象的最后一行
rowsCount = rs.getRow();//检索当前行编号
rs.beforeFirst();//将指针移动到此 ResultSet 对象的开头，正好位于第一行之前
this.rs = rs;
}
/**返回当前页号
*/
public int getCurPage() {
return curPage;
}
/**返回总页数
*/
public int getPageCount() {
if (rowsCount == 0)
return 0;
if (pageSize == 0)
return 1;
// calculate PageCount
double tmpD = (double) rowsCount / pageSize;
int tmpI = (int) tmpD;
if (tmpD > tmpI)
tmpI++;
return tmpI;
}
/**返回当前页的记录条数
*/
public int getPageRowsCount() {
if (pageSize == 0)
return rowsCount;
if (getRowsCount() == 0)
return 0;
if (curPage != getPageCount())
return pageSize;
return rowsCount - (getPageCount() - 1) * pageSize;
}
/**返回分页大小
*/
public int getPageSize() {
return pageSize;
}
/**返回总记录行数
*/
public int getRowsCount() {
return rowsCount;
}
/**转到指定页
*/
public void gotoPage(int page) {
if (rs == null)
return;
if (page < 1)
page = 1;
if (page > getPageCount())
page = getPageCount();
int row = (page - 1) * pageSize + 1;
try {
rs.absolute(row);//将指针移动到此 ResultSet 对象的给定行编号
curPage = page;
} catch (java.sql.SQLException e) {
}
}
/**
* 转到当前页的第一条记录
* @exception java.sql.SQLException 异常说明。
*/
public void pageFirst() throws SQLException {
int row = (curPage - 1) * pageSize + 1;
rs.absolute(row);
}
/**
* 转到当前页的最后一条记录
* @exception java.sql.SQLException 异常说明。
*/
public void pageLast() throws SQLException {
int row = (curPage - 1) * pageSize + getPageRowsCount();
rs.absolute(row);
}
/**设置分页大小
*/
public void setPageSize(int pageSize) {
if (pageSize >= 0) {
this.pageSize = pageSize;
curPage = 1;
}
}
}
/*
* Generated by MyEclipse Struts
* Template path: templates/java/JavaClass.vtl
*/
package com.lyt.struts.action;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import bean.*;
import common.*;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.*;
import dao.ApplicationDAO;
/**
* MyEclipse Struts
* Creation date: 07-14-2007
*
* XDoclet definition:
* @struts.action validate="true"
*/
public class PageAction extends Action {
/*
* Generated Methods
*/
/**
* Method execute
* @param mapping
* @param form
* @param request
public class PageableResultSet extends ResultSet{
protected java.sql.ResultSet rs = null; protected int rowsCount; protected int pageSize; protected int curPage; protected String command = ""; public PageableResultSet(java.sql.ResultSet rs) throws java.sql.SQLException {
if (rs == null) throw new SQLException("given ResultSet is NULL", "user"); rs.last();//将指针移动到此 ResultSet 对象的最后一行 rowsCount = rs.getRow();//检索当前行编号 rs.beforeFirst();//将指针移动到此 ResultSet 对象的开头，正好位于第一行之前 this.rs = rs; } /**返回当前页号 */ public int getCurPage() { return curPage; } /**返回总页数 */ public int getPageCount() { if (rowsCount == 0) return 0; if (pageSize == 0) return 1; // calculate PageCount double tmpD = (double) rowsCount / pageSize; int tmpI = (int) tmpD; if (tmpD > tmpI) tmpI++; return tmpI; } /**返回当前页的记录条数 */ public int getPageRowsCount() { if (pageSize == 0) return rowsCount; if (getRowsCount() == 0) return 0; if (curPage != getPageCount()) return pageSize; return rowsCount - (getPageCount() - 1) * pageSize; } /**返回分页大小 */ public int getPageSize() { return pageSize; } /**返回总记录行数 */ public int getRowsCount() { return rowsCount; } /**转到指定页 */ public void gotoPage(int page) { if (rs == null) return; if (page < 1) page = 1; if (page > getPageCount()) page = getPageCount(); int row = (page - 1) * pageSize + 1; try { rs.absolute(row);//将指针移动到此 ResultSet 对象的给定行编号 curPage = page; } catch (java.sql.SQLException e) { } } /** * 转到当前页的第一条记录 * @exception java.sql.SQLException 异常说明。 */ public void pageFirst() throws SQLException { int row = (curPage - 1) * pageSize + 1; rs.absolute(row); } /** * 转到当前页的最后一条记录 * @exception java.sql.SQLException 异常说明。 */ public void pageLast() throws SQLException { int row = (curPage - 1) * pageSize + getPageRowsCount(); rs.absolute(row); } /**设置分页大小 */ public void setPageSize(int pageSize) { if (pageSize >= 0) { this.pageSize = pageSize; curPage = 1; } }
public boolean next() throws SQLException {
// TODO Auto-generated method stub
return rs.next();
}
}分页action类PageAction.java的关键代码如下：
/* * Generated by MyEclipse Struts * Template path: templates/java/JavaClass.vtl */package com.lyt.struts.action;import javax.servlet.ServletContext;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;import javax.sql.DataSource;import org.apache.struts.action.Action;import org.apache.struts.action.ActionForm;import org.apache.struts.action.ActionForward;import org.apache.struts.action.ActionMapping;import bean.*;import common.*;import java.sql.ResultSet;import java.sql.SQLException;import java.util.*;import dao.ApplicationDAO;/** * MyEclipse Struts * Creation date: 07-14-2007 * * XDoclet definition: * @struts.action validate="true" */public class PageAction extends Action { /* * Generated Methods */ /** * Method execute * @param mapping * @param form * @param request