各种工具类

返回随机字符串Uuid

import java.util.UUID; public final class UuidUtil { private UuidUtil(){} public static String getUuid(){ return UUID.randomUUID().toString().replace("-","");//返回不相同的随机字符串 } }

使用

String str= UuidUtil.getUuid();

获取ip地址

import java.net.InetAddress; @Test public void test04(){ InetAddress addr= null; try { addr = InetAddress.getLocalHost(); } catch (UnknownHostException e) { e.printStackTrace(); } String ip=addr.getHostAddress(); System.out.println(ip); }

验证码

import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.image.BufferedImage; import java.io.IOException; import java.util.Random; import javax.imageio.ImageIO; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @WebServlet("/checkCode") public class CheckCodeServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { //服务器通知浏览器不要缓存 response.setHeader("pragma","no-cache"); response.setHeader("cache-control","no-cache"); response.setHeader("expires","0"); //在内存中创建一个长80，宽30的图片，默认黑色背景 //参数一：长 //参数二：宽 //参数三：颜色 int width = 80; int height = 30; BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB); //获取画笔 Graphics g = image.getGraphics(); //设置画笔颜色为灰色 g.setColor(Color.GRAY); //填充图片 g.fillRect(0,0, width,height); //产生4个随机验证码，12Ey String checkCode = getCheckCode(); //将验证码放入HttpSession中 request.getSession().setAttribute("CHECKCODE_SERVER",checkCode); //设置画笔颜色为黄色 g.setColor(Color.YELLOW); //设置字体的小大 g.setFont(new Font("黑体",Font.BOLD,24)); //向图片上写入验证码 g.drawString(checkCode,15,25); //将内存中的图片输出到浏览器 //参数一：图片对象 //参数二：图片的格式，如PNG,JPG,GIF //参数三：图片输出到哪里去 ImageIO.write(image,"PNG",response.getOutputStream()); } /** * 产生4位随机字符串 */ private String getCheckCode() { String base = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; int size = base.length(); Random r = new Random(); StringBuffer sb = new StringBuffer(); for(int i=1;i<=4;i++){ //产生0到size-1的随机值 int index = r.nextInt(size); //在base字符串中获取下标为index的字符 char c = base.charAt(index); //将c放入到StringBuffer中去 sb.append(c); } return sb.toString(); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request,response); }

验证码使用

<input id="check" name="check" type="text" placeholder="请输入验证码" autocomplete="off"> <span> <img src="${pageContext.request.contextPath}/checkCode" alt="" onclick="changeCheckCode(this)"> </span> <script type="text/javascript"> //图片点击事件 function changeCheckCode(img) { img.src="${pageContext.request.contextPath}/checkCode?"+new Date().getTime(); } </script>

qq邮箱代理发送邮件

1 登陆qq邮箱 点击进入设置 在进入账户 2 开启pop3/smtp服务 3 完成信息验证 4 得到的配置密码 忘记了再生成一次

5 将配置密码填入Mailntil中

import javax.mail.*; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeMessage; import java.util.Properties; /** * 发邮件工具类 */ public final class MailUtils { private static final String USER = "你的qq邮箱"; // 发件人称号，同邮箱地址 private static final String PASSWORD = "你的配置密码"; // 如果是qq邮箱可以使户端授权码，或者登录密码 /** * * @param to 收件人邮箱 * @param text 邮件正文 * @param title 标题 */ /* 发送验证信息的邮件 */ public static boolean sendMail(String to, String text, String title){ try { final Properties props = new Properties(); props.put("mail.smtp.auth", "true"); props.put("mail.smtp.host", "smtp.qq.com"); // 发件人的账号 props.put("mail.user", USER); //发件人的密码 props.put("mail.password", PASSWORD); // 构建授权信息，用于进行SMTP进行身份验证 Authenticator authenticator = new Authenticator() { @Override protected PasswordAuthentication getPasswordAuthentication() { // 用户名、密码 String userName = props.getProperty("mail.user"); String password = props.getProperty("mail.password"); return new PasswordAuthentication(userName, password); } }; // 使用环境属性和授权信息，创建邮件会话 Session mailSession = Session.getInstance(props, authenticator); // 创建邮件消息 MimeMessage message = new MimeMessage(mailSession); // 设置发件人 String username = props.getProperty("mail.user"); InternetAddress form = new InternetAddress(username); message.setFrom(form); // 设置收件人 InternetAddress toAddress = new InternetAddress(to); message.setRecipient(Message.RecipientType.TO, toAddress); // 设置邮件标题 message.setSubject(title); // 设置邮件的内容体 message.setContent(text, "text/html;charset=UTF-8"); // 发送邮件 Transport.send(message); return true; }catch (Exception e){ e.printStackTrace(); } return false; } }

6 MailUtil使用