ExplorerCSharp(小文):我试过你说的去掉return rs;编译时仍然显示一下错误: DB.java:15: unreported exception java.lang.InstantiationException; must be caugh t or declared to be thrown Class.forName(sDBDriver).newInstance(); ^ 1 error去掉上面的.newInstance();就可以通过编译,但是链接后网页无法显示500错误,不知道去掉.newInstance();是不是会影响jdbc链接 loveyousomuch(★爱神厄洛斯★) :谢谢热情出手,感动的雪地里打滚三天三夜^_^
参考了一下微软的帮助在Connecting Through the JDBC Driver Manager 主题下发现如下例子: Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); Connection conn = DriverManager.getConnection ("jdbc:microsoft:sqlserver://server1:1433;User=test;Password=secret"); 还有楼上 loveyousomuch(★爱神厄洛斯★) 兄给的为什么都没有csdn以前给的.newInstance();呢?是不是newInstance是可有可无的? 希望有人能够回答这个问题
已经试过了 loveyousomuch(★爱神厄洛斯★) 的bean和我的bean在链接后都是同一个错误,看来我的bean也算是写对了^_^HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248) javax.servlet.http.HttpServlet.service(HttpServlet.java:856) root cause java.lang.NullPointerException org.apache.jsp.search_jsp._jspService(search_jsp.java:69) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133) javax.servlet.http.HttpServlet.service(HttpServlet.java:856) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248) javax.servlet.http.HttpServlet.service(HttpServlet.java:856) 郁闷中... 谁能给个答案??? 菜鸟深夜期待中
package bbsBean;import java.sql.*;
import java.net.*;
import java.io.*;
import java.util.*;public class QueryData implements Serializable
{
//定义变量
static Connection conn=null;
Statement stmt=null;
ResultSet rs=null;
public QueryData(){}
//建立连接
public static void getConnection(){
try
{
//注册驱动
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
/*建立连接*/
conn=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;User=sa;Password=;DatabaseName=bbs"); }
catch (ClassNotFoundException e)
{
e.printStackTrace();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
//关闭数据库
public void closeConnection(){
try
{
if (rs!=null)
{
rs.close();
}
if (stmt!=null)
{
stmt.close();
}
if (conn!=null)
{
conn.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
rs=null;
stmt=null;
conn=null;
} //returnResultQuery该方法返回一个得到的记录集,参数为sql语句
public ResultSet returnResultQuery(String sql){
rs=null;
try
{
if (conn==null)
{
getConnection();
}
if(conn!=null){
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
//执行数据库的查询
rs=stmt.executeQuery(sql);
}
}
catch (SQLException e)
{
e.printStackTrace();
}
return rs;
} //executeUpdate用来更新数据库
//参数为sql语句,成功返回true,失败返回false;
public boolean executeUpdate(String sql){
boolean bupdate=false;
try
{
//判断是否连接
if (conn==null)
{
getConnection();
}
if(conn!=null){
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
int rowCount=stmt.executeUpdate(sql);
if (rowCount!=0)
{
bupdate=true;
}
}
}
catch (SQLException e)
{
e.printStackTrace();
}
return bupdate;
}
//toChinese方法用于将一个字符串进行中文处理
public static String toChinese(String strValue){
try
{
if (strValue==null)
{
return null;
}
else{
strValue=new String(strValue.getBytes("ISO8856_1"),"GBK");
return strValue;
}
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
//测试代码
/* public static void main(String arge[]){
ResultSet r=null;
QueryData q=new QueryData();
r=q.returnResultQuery("select * from liouyan");
try
{
while (r.next())
{
System.out.println(r.getString(2));
}
}
catch (SQLException e)
{
System.out.println("错误");
}
}
*/
}
DB.java:15: unreported exception java.lang.InstantiationException; must be caugh
t or declared to be thrown
Class.forName(sDBDriver).newInstance();
^
1 error去掉上面的.newInstance();就可以通过编译,但是链接后网页无法显示500错误,不知道去掉.newInstance();是不是会影响jdbc链接
loveyousomuch(★爱神厄洛斯★) :谢谢热情出手,感动的雪地里打滚三天三夜^_^
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
Connection conn = DriverManager.getConnection
("jdbc:microsoft:sqlserver://server1:1433;User=test;Password=secret");
还有楼上 loveyousomuch(★爱神厄洛斯★) 兄给的为什么都没有csdn以前给的.newInstance();呢?是不是newInstance是可有可无的?
希望有人能够回答这个问题
loveyousomuch(★爱神厄洛斯★) 的bean和我的bean在链接后都是同一个错误,看来我的bean也算是写对了^_^HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
root cause java.lang.NullPointerException
org.apache.jsp.search_jsp._jspService(search_jsp.java:69)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
郁闷中...
谁能给个答案???
菜鸟深夜期待中