由于是用mvc这样的框架，所以在c这一层仅仅起到一个转向和收集页面信息的作用，所以这里我有写了一个分页查询的bean，暂时命名是PageCtBean，代码如下：
package com.util;
import com.model.DBUtil;
import java.sql.*;
/**
* Created by IntelliJ IDEA.
* User: 7612ce
* Date: 2005-6-23
* Time: 10:36:57
* To change this template use Options | File Templates.
*/
public class PageCtBean {
public final static int MAX_PAGE_SIZE = Page.MAX_PAGE_SIZE;
protected String countSQL, querySQL;
protected int pageNo,pageSize,startIndex,totalCount;
protected javax.sql.RowSet rowSet;
protected Page setPage;
protected Object[][] objTables=null;
protected Object[][] objCount=null;
protected Object[] obj=null;
public PageCtBean(){
}
/**
* 构造一查询出所有数据的PageStatement
* @param sql query sql
*/
public PageCtBean(String sql){
this(sql,1,MAX_PAGE_SIZE);
}
/**
* 构造一查询出当页数据的PageStatement
* @param sql query sql
* @param pageNo 页码
*/
public PageCtBean(String sql, int pageNo){
this(sql, pageNo, Page.DEFAULT_PAGE_SIZE);
}
/**
* 构造一查询出当页数据的PageStatement，并指定每页显示记录条数
* @param sql query sql
* @param pageNo 页码
* @param pageSize 每页容量
*/
public PageCtBean(String sql, int pageNo, int pageSize){
this.pageNo = pageNo;
this.pageSize = pageSize;
this.startIndex = Page.getStartOfAnyPage(pageNo, pageSize);
this.querySQL = intiQuerySQL(sql, this.startIndex, pageSize);
}
/**
*生成查询一页数据的sql语句
*@param sql 原查询语句
*@ startIndex 开始记录位置
*@ size 需要获取的记录数
*/
protected String intiQuerySQL(String sql, int startIndex, int size){
StringBuffer querySQL = new StringBuffer();
querySQL.append(sql)
.append(" limit ")
.append(startIndex-1 )
.append(",").append(size);
return querySQL.toString();
}
/**
*使用给出的对象设置指定参数的值
*@param obj 包含参数值的对象
*/
public void setObject(Object obj[]) throws SQLException{
this.obj=obj;
}
public void setCountSql(String sql){
this.countSQL=sql;
}
/**
* 执行查询取得一页数据，执行结束后关闭数据库连接
* @return RowSetPage
* @throws SQLException
*/
public Page executeQuery() throws ClassNotFoundException{
System.out.println("executeQueryUsingPreparedStatement");
DBUtil DBean=new DBUtil();
try{
objCount = DBean.doSearch(this.countSQL,obj);
if (!objCount.equals(null)){
System.out.println("the count is ="+objCount[0][0].toString());
totalCount =Integer.parseInt(objCount[0][0].toString()) ;
System.out.println("the count is ="+totalCount);
} else {
totalCount = 0;
}
if (totalCount < 1 )
return null;
objTables= DBean.doSearch(this.querySQL,obj);
this.setPage = new Page(this.objTables,startIndex,totalCount,pageSize);
return this.setPage;
}catch(SQLException sqle){
//System.out.println("executeQuery SQLException");
sqle.printStackTrace();
}catch(Exception e){
e.printStackTrace();
throw new RuntimeException(e.toString());
}
return null;
}
/**
*取封装成Page的查询结果
*@return Page
*/
public Page getPage() {
return this.setPage;
}
}
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