Encapsulating JDBC tool classes

Tool class

package com.htf.util;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

/** 
* JDBC Data operation tool class 
* @author : htf 
* 
*/
public class DBUtils {

	private static String url;
	private static String driverClassName;
	private static String userName;
	private static String password;
	
	static {
		// Utility class loader load properties file 
		// The configuration file must be placed in src Under the path 
		
		// Read the file 
		InputStream is =DBUtils.class.getClassLoader().getResourceAsStream("jdbc_dev.properties");
		Properties prop =new Properties();
		try {
			
			prop.load(is);
			url=prop.getProperty("url");
			userName=prop.getProperty("userName");
			password=prop.getProperty("password");
			
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	/**
	 *  Get database connection 
	 * @return
	 */
	public static Connection getConnection() {
		
		Connection conn =null;
		
		try {
			//
			conn=DriverManager.getConnection(url, userName, password);		
		} catch (Exception e) {
			e.printStackTrace();
		}
		return conn;
	}
	/**
	 *  close JDBC resources , Order of attention 
	 * @param conn
	 * @param stmt
	 * @param rs
	 */
	public static void close(Connection conn,Statement stmt,ResultSet rs) {
		
		try {
			
			if (rs != null) {
				rs.close();
			}
			if (stmt != null) {
				stmt.close();
			}
			if (conn != null) {
				conn.close();
			}
			
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
}

The configuration file

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai
userName=root
password=123456