javabean问题?
数据库study ,表user 字段:username password age qq ;
java代码:
package mybean;
import java.sql.*;
public class DBTest {
private String userName="root";
private String userPasswd="******";
private String dbname="study";
private String tableName="";
public DBTest(){
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(ClassNotFoundException e){
System.out.print(e.toString());
}
}
public void setTableName(String n){
this.tableName=n;
}
public StringBuffer getBuffer(){
StringBuffer buffer=new StringBuffer();
try{
String url="jdbc:mysql://localhost/"+dbname+"?useUnicode=true&characsetEncoding=UTF-8&user="+userName+"&password="+userPasswd;
Connection connection=DriverManager.getConnection(url);
Statement statement = connection.createStatement();
String sql="SELECT * FROM"+tableName;
ResultSet rs = statement.executeQuery(sql);
buffer.append("<table border=1>");
buffer.append("<TR><TD>序号</TD><TD>用户名</TD><TD>年龄</TD><TD>QQ</TD></TR>");
int i=0;
while(rs.next()){
i++;
String username=rs.getString("username");
int age=rs.getInt("age");
String qq=rs.getString("qq");
buffer.append("<TR><TD>"+i+"</TD><TD>"+username+"</TD><TD>"+age+"</TD><TD>"+qq+"</TD></TR>");
}
buffer.append("</table>");
rs.close();
statement.close();
connection.close();
}
catch(SQLException e){
System.out.print(e.toString());
}
return buffer;
}
}
jsp文件代码:
<%@ page contentType="text/html;charset=GBK" %>
<%@ page language="java" %>
<jsp:useBean id="test3" scope="page" class="mybean.DBTest" />
<jsp:setProperty name="test3" property="tableName" value="testbean" />
<html>
<head>
<title>the javabean test</title>
</head>
<body>
<center>
<jsp:getProperty name="test3" property="buffer"/>
</center>
</body>
</html>
运行后,页面一片空白,什么都不显示.请问是哪里出了问题?
谢谢!