package servlet;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;

/*
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*/
/**
*
* @author
*/
public class DatabaseConnection {

private Connection conn;// = null;
public DatabaseConnection() {
   conn = null;
}

public Connection connect(String database){
   try{
         Class.forName("com.mysql.jdbc.Driver");
         conn = DriverManager.getConnection("jdbc:mysql://localhost/" + database,"root", "");

   }catch(ClassNotFoundException e){
   } catch (SQLException e) {
   }
   return conn;
}

public ResultSet query(PreparedStatement stmt){
   ResultSet rs = null;
   try {
         rs = stmt.executeQuery();
   } catch (SQLException ex) {
         Logger.getLogger(DatabaseConnection.class.getName()).log(Level.SEVERE, null, ex);
   }
   return rs;
}
public void close(){
   try {
         if (conn != null)
            conn.close();
   } catch (SQLException ex) {
         Logger.getLogger(DatabaseConnection.class.getName()).log(Level.SEVERE, null, ex);

Write an anonymous PL/SQL block that accepts a string as input and...