我试图从数据库中检索数据并使用ResultSet,但我没有得到所需的输出
主程序:
import java.sql.ResultSet;
import java.sql.SQLException;
import java.lang.reflect.Array;
import java.util.ArrayList;
public class classname_main{
public static void main(String[] args) throws SQLException{
classname abc=new classname();
ResultSet asdf= (ResultSet) abc.runconnect();
abc.printdata();
}
}
类别:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
public class classname{
public static Object runconnect(){
try{
//get connection
Connection connection = DriverManager.getConnection("");
//Create Statement
Statement st = connection.createStatement();
//ex query
//Resultset
ResultSet rs = st.executeQuery("");
float time=9;
while(rs.next())
{
if(time<20){
String x=(rs.getString(9));
Float y=(rs.getFloat(5));
//System.out.println(rs.getString(""));
time=time+duration;
//System.out.println(x);
if(x>=20){
x=9;
}
}
}
return rs;
}
catch(Exception ex){
ex.printStackTrace();
}
return 0;
}
public static Object printdata(){
classname pd = new classname();
ResultSet drs = (ResultSet) pd.runconnect();
System.out.println(drs);
return null;
}
}
输出:
com.mysql.jdbc.JDBC42ResultSet@5910e440
答案 0 :(得分:1)
尝试使用.getString(...)
或.getInt(...)
...来检索所需的值,例如:
System.out.println(drs.getString(some value));
而不是:System.out.println(drs);