java pgAdmin数据库连接

package auto; 
 
import java.sql.DriverManager; 
import java.sql.Connection; 
import java.sql.Statement; 
import java.sql.ResultSet; 
 
public class Jdbc 
{ 
  public static void main(String[] args) throws Exception 
    { 
    Class.forName("org.postgresql.Driver"); 
   String url = "jdbc:postgresql://127.0.0.1:5432/postgres"; 
   String user = "aotuman"; 
    String pwd = "aotuman"; 

    Connection conn = DriverManager.getConnection(url, user, pwd); 
   Statement stmt = conn.createStatement(); 

  String sql = "select * from books "; 
    ResultSet rst = stmt.executeQuery(sql); 
 
  while (rst.next()) 
    { 
      System.out.println(rst.getString(1) + ": " + rst.getString(2)); 
    } 
   rst.close(); 
    stmt.close(); 
    conn.close(); 
   }
}