Java操纵postgresql

package com.howso.deeplan.flink.utils;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class DBUtils {

public static void exec(String sql) {
System.out.println(" this is a test ");
try {
Class.forName("org.postgresql.Driver").newInstance();
String url = "jdbc:postgresql://192.168.0.220:5432/MR";
Connection con = DriverManager.getConnection(url, "MR","mr");
Statement st = con.createStatement();
ResultSet rs = st.executeQuery(sql);
rs.close();
st.close();
con.close();

} catch (Exception ee) {
System.out.println(ee);
}
}
}