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分享大大们帮我看看,为什么返回的是NULL
如下是jsp部分;
<TITLE>test
</TITLE>
</HEAD>
<BODY BGCOLOR="#FDF5E6">
<H1 ALIGN="CENTER">Connect JO
</H1>
<%@ page language="java" %>
<%@ page import="java.sql.*" %>
<%@ page import="javax.naming.*" %>
<jsp:useBean id="a" scope="page" class="com.DBConnection" />
<%a.TestDBConnection();
out.println(a.getConnection());
%>
</BODY>
</HTML>
如下是bean部分:
package com;
import java.sql.*;
import javax.naming.*;
public class DBConnection{
private Connection con;
public DBConnection(){
}
public Connection getConnection(){
return con;
}
public void remove(){
try{
con.close();
}catch (SQLException ex){
ex.printStackTrace ();
}
}
public void connectDriverManager(String url,String drv,String user,String pwd){
try{
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
con = DriverManager.getConnection (url,user,pwd);
}catch (SQLException ex) {
printSQLException(ex);
}catch (Exception ex) {
ex.printStackTrace();
}
}
public void TestDBConnection(){
String url="jdbc:oracle:thin:@192.168.0.27:1521:oracle";
String drv="com.oracle.jdbc.OracleDriver" ;
connectDriverManager(url,drv,"xdhua","softvan");
}
public static void printSQLException(SQLException ex){
// A SQLException was generated. Catch it and
// display the error information. Note that there
// could be multiple error objects chained
// together
System.out.println ("\n*** SQLException caught ***\n");
while (ex != null) {
System.out.println ("SQLState: " + ex.getSQLState ());
System.out.println ("Message: " + ex.getMessage ());
System.out.println ("Vendor: " + ex.getErrorCode ());
ex = ex.getNextException ();
System.out.println ("");
}
}
}
调用后返回的是一个NULL.......参数没有问题,是不是程序哪里出了茬子啊,各位大大们帮忙看看.
<TITLE>test
</TITLE>
</HEAD>
<BODY BGCOLOR="#FDF5E6">
<H1 ALIGN="CENTER">Connect JO
</H1>
<%@ page language="java" %>
<%@ page import="java.sql.*" %>
<%@ page import="javax.naming.*" %>
<jsp:useBean id="a" scope="page" class="com.DBConnection" />
<%a.TestDBConnection();
out.println(a.getConnection());
%>
</BODY>
</HTML>
如下是bean部分:
package com;
import java.sql.*;
import javax.naming.*;
public class DBConnection{
private Connection con;
public DBConnection(){
}
public Connection getConnection(){
return con;
}
public void remove(){
try{
con.close();
}catch (SQLException ex){
ex.printStackTrace ();
}
}
public void connectDriverManager(String url,String drv,String user,String pwd){
try{
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
con = DriverManager.getConnection (url,user,pwd);
}catch (SQLException ex) {
printSQLException(ex);
}catch (Exception ex) {
ex.printStackTrace();
}
}
public void TestDBConnection(){
String url="jdbc:oracle:thin:@192.168.0.27:1521:oracle";
String drv="com.oracle.jdbc.OracleDriver" ;
connectDriverManager(url,drv,"xdhua","softvan");
}
public static void printSQLException(SQLException ex){
// A SQLException was generated. Catch it and
// display the error information. Note that there
// could be multiple error objects chained
// together
System.out.println ("\n*** SQLException caught ***\n");
while (ex != null) {
System.out.println ("SQLState: " + ex.getSQLState ());
System.out.println ("Message: " + ex.getMessage ());
System.out.println ("Vendor: " + ex.getErrorCode ());
ex = ex.getNextException ();
System.out.println ("");
}
}
}
调用后返回的是一个NULL.......参数没有问题,是不是程序哪里出了茬子啊,各位大大们帮忙看看.
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