how can you retrive information from database by using
hashmap/arraylist ,plz explain with example briefly?
Answer / none
import java.util.*;
import java.sql.*;
public class Jdbc
{
public static void main(String[] a)
{
Connection conn=null;
try
{
String s1="Driver name for registration";
Class.forname(s1);
String url="Driver Port No name";
String username="Database Username";
String password="Database password";
conn=Drivermanager.getConnection(url,username,password);
String sql="SELECT name,address FROM tb"
Statement stmt=conn.createStatement(sql);
Resultset rs=stmt.executeQuery();
ArrayList al=new List();
while(rs.hasnext())
{
al.add(index,rs.getString());
}
rs.close();
stmt.close();
conn.close();
}
//handle Exceptions
}
}
| Is This Answer Correct ? | 8 Yes | 4 No |
In the HashMap, we know the values but we dont know the key, then how can we get the key from HashMap ?????
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