ResultSet 的问题!!在线等!菜鸟求救
我的程序是这样的:
package brick0906;
import java.sql.*;
import java.sql.Date;
import java.util.*;
import java.io.*;
public class ArrayListText {
public static String drivername="oracle.jdbc.driver.OracleDriver";
public Connection conn=null;
ResultSet rs=null;
String classno=null;
String classname=null;
String classteacher=null;
//Date classdate=null;
public static void main(String args []) throws ClassNotFoundException, SQLException, IOException{
ArrayListText ar=new ArrayListText();
ArrayList al=new ArrayList();
ar.conninit();
ar.select();
al.add(ar.classno);
al.add(ar.classname);
al.add(ar.classteacher);
PrintWriter pw =new PrintWriter(new FileWriter(new File("F://java.txt")));
pw.println(al.get(0));
pw.println(al.get(1));
pw.println(al.get(2));
pw.close();
ar.connclose();
}
public void conninit() throws ClassNotFoundException, SQLException{
Class.forName(drivername);
String url="jdbc:oracle:thin:@169.254.179.82:1521:brick";
conn=DriverManager.getConnection(url,"brick","brick");
}
public void connclose() throws SQLException{
conn.close();
}
public void select() throws SQLException{
Statement ps=null;
String sql="select * from classinfo";
ps=conn.createStatement();
rs=ps.executeQuery(sql);
while(rs.next()){
this.classno=rs.getString("classno");
this.classname=rs.getString("classname");
this.classteacher=rs.getString("classteacher");
}
}
}
这样的话,我只能在java.txt中显示查询的最后一行,但是我要每行都显示.我弄了很久没搞出来,头都大了,各位大哥帮帮