- 论坛徽章:
- 0
|
请帮一下忙，我找不到出错的地方在那里，多谢了。
package database;
import java.sql.*;
import java.lang.*;
public class ConnDb
{
private Connection connection=null;//变量声明
private Statement statement=null;
private ResultSet rs=null;
private String msg="";
//连接数据库
public void getConn()
{
try{
loadMysql("mydata","root","111" ;//调用方法加载mysql驱动
statement = connection.createStatement();
}catch(Exception e)
{
msg=e.toString()+"数据库连接出错";
}
}
public ResultSet selectDb(String sql) //查询数据库
{
try{
rs = statement.executeQuery(sql);
return rs;
}
catch(Exception e)
{
msg="数据库查询出错"+e.toString();
return null;
}
}
//***************************
//连接Mysql
public void loadMysql(String database,String user,String password)
{
try{
Class.forName("com.mysql.jdbc.Driver";
String url = "jdbc:mysql://localhost/"+database;
connection=DriverManager.getConnection(url,user,password);
}
catch(ClassNotFoundException ex)
{
msg="数据库类载入出错"+ex.toString();
}
catch(SQLException SQLex)
{
msg="数据库载入出错"+SQLex.toString();
}
catch(Exception e)
{
msg="数据库最终出错"+e.toString();
}
}
//***************************
//连接Sqlserver
public void loadsqlDriver(String database,String user,String password)
{
try{
String sDBDriver="com.microsoft.sqlserver.jdbc.SQLServerDriver";
String connectionUrl = "jdbc:sqlserver://localhost:1433;databaseName="+database;
Class.forName(sDBDriver);
connection=DriverManager.getConnection(connectionUrl,user,password);
}
catch(ClassNotFoundException ex)
{
msg="数据库类载入出错"+ex.toString();
}
catch(SQLException SQLex)
{
msg="数据库载入出错"+SQLex.toString();
}
}
//***************************
//连接oracle
public void loadoracleDriver(String database,String user,String password)
{
try{
Class.forName("oracle.jdbc.driver.OracleDriver";//连接oracle
String url= "jdbc racle:thin localhost:1521:"+database;//ORCL
connection=DriverManager.getConnection(url,user,password);
}
catch(ClassNotFoundException ex)
{
msg="数据库类载入出错"+ex.toString();
}
catch(SQLException SQLex)
{
msg="数据库载入出错"+SQLex.toString();
}
}
//******************************************************************************************************************
//更新数据库
public int updateDb(String sql) //更新数据库
{
try{
int s = statement.executeUpdate(sql);
return s;
}
catch(Exception e)
{
msg="数据库更新出错"+e.toString();
return 0;
}
}
//******************************************************************************************************************
//关闭数据库
public void closeDb() //关闭数据库
{
try{
if(rs!=null)
rs.close();
if(statement!=null)
statement.close();
if(connection!=null)
connection.close();
}
catch(Exception e)
{
msg="数据库关闭出错"+e.toString();
}
}
public static void main(String[] args)
{
/*
ConnDb db = new ConnDb();
db.getConn();
String sql = "select mainid,subject1 from nmaintbl limit 0,5";
ResultSet ss = db.selectDb(sql);
if(ss!=null){
try{
while(ss.next())
{
System.out.println(ss.getString(1));
System.out.println(ss.getString(2));
}
}catch(Exception e)
{
System.out.println("数据有错";
}
}
else{
System.out.println("失败";
}
*/
}
}
D:\MyJavaClass>java ConnDb
Exception in thread "main" java.lang.NoClassDefFoundError: ConnDb (wrong name: d
atabase/ConnDb)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source) |
|
免费注册
发表于 2008-07-25 12:06
