postgresql数据库怎么利用Java进行连接

package test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class HelloWorld {  public static void main(String []args) {    Connection connection=null;    Statement statement =null;    try{      String url="jdbc:postgresql://127.0.0.1:5432/postgis";      String user="postgres";      String password = "123456";      Class.forName("org.postgresql.Driver");      connection= DriverManager.getConnection(url, user, password);      System.out.println("是否成功连接pg数据库"+connection);      String sql="select name from test";      statement=connection.createStatement();      ResultSet resultSet=statement.executeQuery(sql);      while(resultSet.next()){        String name=resultSet.getString(1);        System.out.println(name);      }    }catch(Exception e){      throw new RuntimeException(e);    }finally{      try{        statement.close();      }      catch(SQLException e){        e.printStackTrace();        throw new RuntimeException(e);      }finally{        try{          connection.close();        }        catch(SQLException e){          e.printStackTrace();          throw new RuntimeException(e);        }      }    }  }}