100分求：上次一csdn网友发的『汤母猫5数据库连接池 + JavaBean + 分页技术 + JDBC3.0 +大型数据库』的源代码

楼主，有的话给我也发一个
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[email protected]
[email protected]
我也要啊,谢谢啦!!!!!!!

[email protected]
我也要啊,谢谢啦!!!!!!!

楼主，有的话给我也发一个
[email protected]
我研究的两天了，做了一个JavaBeans，但是就是条不同现在发给大家，一起研究一下吧
我编写的连接数据库的JavaBeans DatabaseConn.java 如下：package lguo;
import java.sql.*;
import javax.naming.*;
import javax.sql.DataSource;
//一个用于查找数据源的工具类
public class DatabaseConn
{
static DataSource ds;
private Connection conn;
private Statement stmt;
ResultSet rst;
public static synchronized Connection getConection() throws Exception
{
try
{
Context initCtx = new javax.naming.InitialContext();
Context envCtx = (Context) initCtx.lookup("java:comp/env");
DataSource ds = (DataSource)envCtx.lookup("jdbc/dcs");return ds.getConnection();
}
catch (SQLException e)
{
throw e;
}
catch (NamingException e)
{
throw e;
}}
public ResultSet executeQuery(String sql)
{
rst = null;
try {
conn=ds.getConnection();
stmt=conn.createStatement();
rst = stmt.executeQuery(sql);
}
catch(SQLException ex) {
System.out.println("aq.executeQuery: " + ex.getMessage());
}
return rst;
}
public void executeUpdate(String sql)
{
stmt = null;
rst = null;
try {
conn=ds.getConnection();
stmt=conn.createStatement();
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
catch(SQLException ex) {
System.out.println("aq.executeQuery: " + ex.getMessage());
}
}
public void closeStmt()
{ try {
stmt.close();
}
catch(SQLException e)
{
e.printStackTrace();
}}
public void closeConn()
{ try {
conn.close();
}
catch(SQLException e)
{
e.printStackTrace();
}}} 页面代码test_db.jsp 为：
<%@ page import="lguo.DatabaseConn"%>
<jsp:useBean id="aaa" class="lguo.DatabaseConn" scope="page" >
<% ResultSet rst;
String sql="";try{// Connection conn=DatabaseConn.getConnection();
sql = "select * from [file]";
rst = aaa.executeQuery(sql);
while(rst.next()){
out.println(rst.getString(1));
}
}
catch(Exception ex){
ex.printStackTrace();
}
%>运行后出现错误：执行后网页出现java.lang.NullPointerException

数据库连接池+JavaBean+JSP+SQL Server+JDBC3.0的数据库分页技术
3天没合眼，终于开发出“数据库连接池+JavaBean+JSP+SQL Server+JDBC3.0的数据库分页技术”，现公布全部开发代码，有不好之处请高手指点3天没合眼，
终于开发出“数据库连接池+JavaBean+JSP+SQL Server+JDBC3.0的数据库分页技术”，
现公布全部开发代码，有不好之处请高手指点。
主要特色：
1.使用最新的JDBC3.0数据库驱动。
2.大幅度减化了JSP的反复调用JavaBean,可以直接写SQL,无须再使用连接数据库连接池。
3.将大量的工作交给JavaBean做,JSP负责页面控制。
4.最大特色是极其简单,程序编写也极其简单,非常适合初学者。
5.使用的是"汤母猫"数据库连接池,方便快速。请提供E_mail,为大家分享，如有高手，请指点不是。本人E_mail：[email protected],望多提意见。
****************************************文件名《page.jsp》*******************************************************************
文件名《page.jsp》
<%@ page language="java" import="java.sql.*, my.*" %>
<%@ page contentType="text/html; charset=gb2312" %>
<jsp:useBean id="pagi" scope="page" class="my.Pagi"/>
<html>
<body>
<table align="center" border=1>
<%
String CountQuery="select count(*) from 商品资料";
String query = "select * from 商品资料";
ResultSet rs = pagi.querySql(CountQuery,query, request);
String footer = pagi.PageFooter();
%>
<tr>
<td >商品编号</td>
<td >商品名称</td>
</tr>
<%
if (pagi.intPageCount>0)
{
int i=0;
while (rs.next())
{
i++;
if (i>((pagi.intPage-1)*pagi.intPageSize) &&(i<=pagi.intPage*pagi.intPageSize))
{
%>
<tr>
<td><%=rs.getString(1)%></td>
<td><%=rs.getString(2)%></td>
</tr>
<%
}
}
}
out.println("<tr><td colspan=2>"+footer+"</td></tr>");
rs.close();
pagi.close_all();
%>
</table>
</body>
</html>
****************************************文件名《pagi.java》*********************************************************文件名《pagi.java》
package my; import java.util.*;
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import my.DB.*;public class Pagi
{
ResultSet CountTopicrs=null; //初始化总记录数Rs变量
ResultSet Pagirs=null; //初始化分页时Rs变量
public int intCountTopic=0; //主题总数
public int intPageSize;//每页显示主题数
public int intPageCount;//总页数
public int intPage=1; //当前页数
public String nowPage; // int i;
public String HttpFile;//初始化当前页intPage变量，以准确便获取当前页。 //当前的地址栏的文件
DB db; //定义Linkdb类的一个对象。public Pagi()//定义构造器，初始化每页显示的主题数和数据库的连接。
{
intPageSize=4; //每页显示的记录数目
db = new DB();
}//Countsql:总记录的Query字符串。[形式为select count(*) from tablename]
//Pagisql :要分页的Query字符串。[形式为select * from tablename where ...]
//request :参数传递过程中的变量。[用来控制翻页时的pages变量]
public ResultSet querySql(String Countsql,String Pagisql,HttpServletRequest request)throws Exception
{
HttpFile=request.getRequestURI(); //获取当前文件名。
nowPage=request.getParameter("pages"); //获取当前页，将数值赋予intPage变量。[分页栏中必须要有pages参数]
if (nowPage==null)
{
intPage=1;
}
else
{
intPage=Integer.parseInt(nowPage);
if (intPage<1)
intPage=1;
} CountTopicrs=db.executeQuery(Countsql); //@@@@@@@@@@@@获取总记录数的结果集。 if (CountTopicrs.next())
{
intCountTopic=CountTopicrs.getInt(1);
}
intPageCount = (intCountTopic+intPageSize-1)/intPageSize; //获取总页数。if (intPage>intPageCount)//如果当前页大于总页数，则当前页等于总页数。
{
intPage=intPageCount;
}
CountTopicrs.close(); //关闭总主题数的数据集。
 db.close_all();
Pagirs=db.executeQuery(Pagisql); //@@@@@@@@@@@@@@@获取执行分页的结果集。
return Pagirs;
}//end querySql function.
public int getCountTopic()//获取记录总数。
{
return intCountTopic;
}
public int getPageCount() //获取总页数。
{
return intPageCount;
}
public int getIntPage() //获取当前页数。
{
return intPage;
} public String PageFooter()
{
String str = "";
int next, prev;
prev=intPage-1;
next=intPage+1;
str += "查询到"+getCountTopic()+"条记录"+
" 共"+getPageCount()+"页";
str +=" 第"+getIntPage()+"页 ";
if(intPage>1)
str += " <A href=" + HttpFile + "?pages=1"+">首页</A> ";
else
str += " 首页 ";
if(intPage>1)
str += " <A href=" + HttpFile + "?pages=" + prev + ">上一页</A> ";
else
str += " 上一页 ";
if(intPage<intPageCount)
str += " <A href=" + HttpFile + "?pages=" + next + ">下一页</A> ";
else
str += " 下一页 ";
if(intPageCount>1&&intPage!=intPageCount)
str += " <A href=" + HttpFile + "?pages=" + intPageCount +
">尾页</A>";
else
str += " 尾页 "; return str;
}
 public void close_all()
{
 db.close_all();
}
}************************************************文件名《DB.java》********************************************************
文件名《DB.java》
package my;import java.sql.*;
import javax.naming.*;
import javax.sql.DataSource;
//一个用于查找数据源的工具类。
public class DB {
private Connection con=null;
private Statement stmt=null;
ResultSet rs=null;public ResultSet executeQuery(String sql) throws Exception
{
rs=null;
try
{
Context initCtx = new javax.naming.InitialContext();
 Context envCtx = (Context) initCtx.lookup("java:comp/env");
 DataSource ds = (DataSource)envCtx.lookup("jdbc/bn");
 con=ds.getConnection();
 stmt=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=stmt.executeQuery (sql);
}
catch(SQLException e){throw e;}
catch(NamingException e){throw e;}return rs;
}
 //执行Insert,Update语句
public void executeUpdate(String sql) throws Exception
{
stmt = null;
rs=null;
try
{
 Context initCtx = new javax.naming.InitialContext();
 Context envCtx = (Context) initCtx.lookup("java:comp/env");
 DataSource ds = (DataSource)envCtx.lookup("jdbc/bn");
 con=ds.getConnection();
 stmt=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
stmt.executeQuery(sql);
stmt.close();
con.close();
}
catch(SQLException ex)
{
System.err.println("执行SQL语句出错: " + ex.getMessage());
}
}
// 关闭stmt和关闭连接
public void close_all()
{
try{
stmt.close();
con.close();
}
catch(SQLException e){e.printStackTrace();}
}
}
***************************************《汤母猫中的数据库连接池的设置》********************************************************************************
……
……
……
<Context path="/SQL" docBase="D:\SQL_JSP" debug="0" reloadable="true" crossContext="true">
 <Resource name="jdbc/bn" auth="Container" type="javax.sql.DataSource"/>
<ResourceParams name="jdbc/bn">
 <parameter>
 <name>factory</name>
 <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
 </parameter> <parameter>
 <name>driverClassName</name>
 <value>com.microsoft.jdbc.sqlserver.SQLServerDriver</value>
 </parameter> <parameter>
 <name>url</name>
 <value>jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=jspdev</value>
 </parameter> <parameter>
 <name>username</name>
 <value>cyg</value>
 </parameter> <parameter>
 <name>password</name>
 <value>325345353</value>
 </parameter> <parameter>
 <name>maxActive</name>
 <value>20</value>
 </parameter> <parameter>
 <name>maxIdle</name>
 <value>20</value>
 </parameter> <parameter>
 <name>maxWait</name>
 <value>-1</value>
 </parameter>
</ResourceParams>
</Context>
 </Host> </Engine> </Service></Server>

lguo_714(凌) ( ) :你能给我发一份吗？
100分相谢

[email protected]
要分的也可以说话~~

这里也来一分吧! 学习中
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先谢过!

谁有，也给我一份谢谢
[email protected]

来一份学习一下。谢谢！
[email protected]

package displayNews;import java.sql.*;
import dbLinkConfig.*;
public class DisplayNews
{
String newsTitle,newsContent;
Connection con;
Statement sql;
ResultSet rs;
NewsDBLink db=new NewsDBLink();
String dbDriver=db.dbDriver;
String dbUser=db.dbUser;
String dbPassword=db.dbPassword;
String dbName=db.dbName;
public DisplayNews()
{
try
{
Class.forName(dbDriver);
}
catch(ClassNotFoundException e)
{}
}
public void setNewsTitle(String newsTitle)
{
this.newsTitle=newsTitle;
}
public String getNewsTitle()
{
return newsTitle;
}
public void setNewsContent(String newsContent)
{
this.newsContent=newsContent;
}
public String getNewsContent()
{
return newsContent;
}
public StringBuffer getSelectNewsFS()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 5 * from newsContent where newsArea='抚顺新闻' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
if((newsTitle).trim().length()>30)
{
newsTitle=newsTitle.substring(0,30);
newsTitle+="...";
}
buffer.append("<li><a href=displayNews/displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a></li>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
public StringBuffer getSelectNewsFSOrder15()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 15 * from newsContent where newsArea='抚顺新闻' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
if((newsTitle).trim().length()>40)
{
newsTitle=newsTitle.substring(0,40);
newsTitle+="...";
}
buffer.append("<li><a href=displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a></li>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
public StringBuffer getSelectNewsAll20()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 25 * from newsContent where newsArea<>'站内公告' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
java.util.Date d=rs.getDate(2);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
String area=rs.getString(5);
if((newsTitle).trim().length()>30)
{
newsTitle=newsTitle.substring(0,30);
newsTitle+="...";
}
buffer.append("<li><a href=displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a> ("+area.substring(0,2)+") "+d+"</li>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
public StringBuffer getSelectNewsOther()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 5 * from newsContent where newsArea<>'站内公告' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
if((newsTitle).trim().length()>30)
{
newsTitle=newsTitle.substring(0,30);
newsTitle+="...";
}
buffer.append("<li><a href=displayNews/displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a></li>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
public StringBuffer getSelectNewsOtherOrder15()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 15 * from newsContent where newsArea<>'抚顺新闻' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
if((newsTitle).trim().length()>40)
{
newsTitle=newsTitle.substring(0,40);
newsTitle+="...";
}
buffer.append("<li><a href=displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a></li>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
public StringBuffer getSelectNewsShort()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 10 * from newsContent order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
buffer.append("<tr>");
newsTitle=rs.getString(3);
buffer.append("<td ><a href=showNews.jsp?newsId="+rs.getInt(1)+">"+newsTitle+"</a></td></tr>");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333");
}
}
public String getSelectNewsContent()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 15 * from newsContent order by newsId desc";
rs=sql.executeQuery(condition);
while(rs.next())
{
newsContent=rs.getString(4);
}
con.close();
return newsContent;
}
catch(SQLException e)
{
return newsContent;
}
}
public StringBuffer getSelectNewsWebInsid()
{
try
{
con=DriverManager.getConnection(dbName,dbUser,dbPassword);
sql=con.createStatement();
String condition="select top 8 * from newsContent where newsArea='站内公告' order by newsId desc";
rs=sql.executeQuery(condition);
StringBuffer buffer=new StringBuffer();
while(rs.next())
{
int a=rs.getInt(1);
newsTitle=rs.getString(3);
newsContent=rs.getString(4);
if((newsTitle).trim().length()>10)
{
newsTitle=newsTitle.substring(0,10);
newsTitle+="...";
}
buffer.append("<a href=displayNews/displayNews.jsp?newsId="+a+" target=_blank>"+newsTitle+"</a> ");
}
con.close();
return buffer;
}
catch(SQLException e)
{
return new StringBuffer("3333"+e.toString());
}
}
}

package lawSystem;public class PageNumber1
{
int rowCount=1,//总的页记录数
pageSize=1,//每页显示的记录数
showPage=1,//设置欲显示的页码数
pageCount=1;//分页之后的总页数
public void setRowCount(int n)
{
rowCount=n;
}
public int getRowCount()
{
return rowCount;
}
public void setPageCount(int r,int p)
{
rowCount=r;
pageSize=p;
int n=(rowCount%pageSize)==0?(rowCount/pageSize):(rowCount/pageSize+1);
pageCount=n;
}
public int getPageCount()
{
return pageCount;
}
public void setShowPage(int n)
{
showPage=n;
}
public int getShowPage()
{
return showPage;
}
public void setPageSize(int n)
{
pageSize=n;
}
public int getPageSize()
{
return pageSize;
}
}

调试易

100分求：上次一csdn网友发的『汤母猫5数据库连接池 + JavaBean + 分页技术 + JDBC3.0 +大型数据库』的源代码

解决方案 »