问题遇到的现象和发生背景
问题相关代码,请勿粘贴截图
这是servlet文件
package haut.hati.wjy.control;
import haut.hati.wjy.bean.*;
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class Case01Servlet extends HttpServlet{
public void init(ServletConfig config) throws ServletException{
super.init(config);
}
public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{
//创建对象
Case01Bean bean=new Case01Bean();
request.setAttribute("bean", bean);
//接受request传来的对象
String age=request.getParameter("age");
int p=Integer.parseInt(age);
try{
Class.forName("com.mysql.jdbc.Driver");
}catch(Exception e){}
Connection con;
Statement sql;
ResultSet rs;
try{
String uri="jdbc:mysql://127.0.0.1/student108wjy";
String user="root";
String password="123456";
con=DriverManager.getConnection(uri, user, password);
sql=con.createStatement();
String condition="SELECT * FROM wiystuinfo where 年龄 >"+p;
rs=sql.executeQuery(condition);
//更新columname模型
ResultSetMetaData metaData=rs.getMetaData();
int columnCount=metaData.getColumnCount(); //得到结果集的列数
String [] columnName=new String[columnCount];
for(int i=0; i<columnName.length;i++){
columnName[i]=metaData.getColumnName(i+1);
}
bean.setColumname(columnName);
rs.last();
int rowNumber=rs.getRow(); //得到记录数
String [][] tableRecord=bean.getTableRecord();
tableRecord=new String[rowNumber][columnCount];
rs.beforeFirst();
int i=0;
while(rs.next()){
for(int k=0;k<columnCount;k++){
tableRecord[i][k]=rs.getString(k+1);
}
i++;
}
bean.setTableRecord(tableRecord);
con.close();
RequestDispatcher dispatcher=request.getRequestDispatcher("case01wjyshow.jsp");
dispatcher.forward(request, response);
}catch(SQLException e){
System.out.print(e);
}
}
public void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{
doPost(request,response);
}
}
运行结果及报错内容
之后回报HTTP Status 500 - Error instantiating servlet class haut.hati.wjy.control.Case01Servlet,错误,无法识别Servlet,不能生成class文件,又是也会报404错误。