代码片段

发送邮件

package com.boomoom.store.utils;

import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.Message.RecipientType;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

/**
 * 发送邮件的工具类:
 * @author admin
 *
 */
public class MailUtils {

    public static void sendMail(String to, String subject ,String content){
        
        try {
            // 获得连接:
            Properties props = new Properties();
            Session session = Session.getInstance(props, new Authenticator() {

                @Override
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication("service@store.com", "111");
                }
                
            });
            // 构建邮件:
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress("service@store.com"));
            // 设置收件人:
            // TO:收件人   CC:抄送   BCC:暗送,密送.
            message.addRecipient(RecipientType.TO, new InternetAddress(to));
            // 主题:
            message.setSubject(subject);
            // 正文:
            message.setContent(context, "text/html;charset=UTF-8");
        
            // 发送邮件:
            Transport.send(message);
        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }
    
    public static void main(String[] args) {
        MailUtils.sendMail("aaa@store.com", "sdfjklsdkljrsiduoigittery");
    }
}

String to Json

判断字符串是否为空，字符串是否为json
list转json用JSONArray,对象和map转json用JSONObject，JSONObject.parse/.parseObject

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;

public class Util {
    public static boolean isJSONMessage(String textMessage) {
        if (isBlank(textMessage)) {
            return false;
        }

        try {
            Object Object = JSONObject.parse(textMessage);
            if (object instanceof JSONObject || object instanceof JSONArray) {
                return true;
            }
        } catch (Exception e) {
        }
        
        return false;
    }

    public static isBlank(String str) {
        int length;

        if ((str == null) || ((length = str.length()) == 0) ) {
            return false;
        }

        for (int i = 0; i < length; i++) {
            if (Character.isWhitespace(str.charAt(i))) {
                return false;
            }
        }
    }
}

EHcache使用Demo

package com.boomoom.shop.service.impl;

import java.sql.SQLException;
import java.util.List;

import com.boomoom.shop.dao.CategoryDao;
import com.boomoom.shop.dao.impl.CategoryDaoImpl;
import com.boomoom.shop.domain.Category;
import com.boomoom.shop.service.CategoryService;
import com.boomoom.shop.utils.BeanFactory;

import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
/**
 * 分类的Service的实现类
 * @author admin
 *
 */
public class CategoryServiceImpl implements CategoryService {

    @Override
    public List<Category> findAll()throws SQLException {
        /**
         * 使用缓存优化程序,先从缓存中获取数据
         * 获取到:直接返回
         * 获取不到:查询数据库,将记录存入到缓存中.
         */
        // 读取配置文件
        CacheManager cacheManager = CacheManager.create(CategoryServiceImpl.class.getClassLoader().getResourceAsStream("ehcache.xml"));
        // 从配置文件中获取名称为categoryCache缓存区
        Cache cache = cacheManager.getCache("categoryCache");
        // 判断缓存中是否有list集合:
        Element element = cache.get("list");
        List<Category> list = null;
        if(element == null){
            // 缓存中没有数据
            System.out.println("缓存中没有数据 ,查询数据库=====");
            
            // CategoryDao categoryDao = new CategoryDaoImpl();
            CategoryDao categoryDao = (CategoryDao) BeanFactory.getBean("categoryDao");
            list = categoryDao.findAll();
            element = new Element("list",list); 
            cache.put(element);
        }else{
            // 缓存中已经存在数据
            System.out.println("缓存中有数据 ,没有查询数据库=====");
            list = (List<Category>)element.getObjectValue();
            
        }
        return list;
    }
}

<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../config/ehcache.xsd">

    <diskStore path="C:/ehcache"/>
    <cache
        name="categoryCache"
            maxElementsInMemory="10000"
            eternal="false"
            timeToIdleSeconds="120"
            timeToLiveSeconds="120"
            overflowToDisk="true"
            maxElementsOnDisk="10000000"
            diskPersistent="false"
            diskExpiryThreadIntervalSeconds="120"
            memoryStoreEvictionPolicy="LRU"
            />
</ehcache>

生成验证码图片

package com.boomoom.store.web.servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 生成验证码图片
 * 以防浏览器缓存，可以在jsp的访问路径后跟一个任意参数(当前时间)
 * 
 */
public class CheckImgServlet extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // 禁止缓存
        // response.setHeader("Cache-Control", "no-cache");
        // response.setHeader("Pragma", "no-cache");
        // response.setDateHeader("Expires", -1);

        int width = 120;
        int height = 30;

        // 步骤一 绘制一张内存中图片
        BufferedImage bufferedImage = new BufferedImage(width, height,
                BufferedImage.TYPE_INT_RGB);

        // 步骤二 图片绘制背景颜色 ---通过绘图对象
        Graphics graphics = bufferedImage.getGraphics();// 得到画图对象 --- 画笔
        // 绘制任何图形之前 都必须指定一个颜色
        graphics.setColor(getRandColor(200, 250));
        graphics.fillRect(0, 0, width, height);

        // 步骤三 绘制边框
        graphics.setColor(Color.WHITE);
        graphics.drawRect(0, 0, width - 1, height - 1);

        // 步骤四 四个随机数字
        Graphics2D graphics2d = (Graphics2D) graphics;
        // 设置输出字体
        graphics2d.setFont(new Font("宋体", Font.BOLD, 18));

        String words =
         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890";
        // String words = "u7684u4e00u4e86u662fu6211u4e0du5728u4ebau4eecu6709u6765u4ed6u8fd9u4e0au7740u4e2au5730u5230u5927u91ccu8bf4u5c31u53bbu5b50u5f97u4e5fu548cu90a3u8981u4e0bu770bu5929u65f6u8fc7u51fau5c0fu4e48u8d77u4f60u90fdu628au597du8fd8u591au6ca1u4e3au53c8u53efu5bb6u5b66u53eau4ee5u4e3bu4f1au6837u5e74u60f3u751fu540cu8001u4e2du5341u4eceu81eau9762u524du5934u9053u5b83u540eu7136u8d70u5f88u50cfu89c1u4e24u7528u5979u56fdu52a8u8fdbu6210u56deu4ec0u8fb9u4f5cu5bf9u5f00u800cu5df1u4e9bu73b0u5c71u6c11u5019u7ecfu53d1u5de5u5411u4e8bu547du7ed9u957fu6c34u51e0u4e49u4e09u58f0u4e8eu9ad8u624bu77e5u7406u773cu5fd7u70b9u5fc3u6218u4e8cu95eeu4f46u8eabu65b9u5b9eu5403u505au53ebu5f53u4f4fu542cu9769u6253u5462u771fu5168u624du56dbu5df2u6240u654cu4e4bu6700u5149u4ea7u60c5u8defu5206u603bu6761u767du8bddu4e1cu5e2du6b21u4eb2u5982u88abu82b1u53e3u653eu513fu5e38u6c14u4e94u7b2cu4f7fu5199u519bu5427u6587u8fd0u518du679cu600eu5b9au8bb8u5febu660eu884cu56e0u522bu98deu5916u6811u7269u6d3bu90e8u95e8u65e0u5f80u8239u671bu65b0u5e26u961fu5148u529bu5b8cu5374u7ad9u4ee3u5458u673au66f4u4e5du60a8u6bcfu98ceu7ea7u8ddfu7b11u554au5b69u4e07u5c11u76f4u610fu591cu6bd4u9636u8fdeu8f66u91cdu4fbfu6597u9a6cu54eau5316u592au6307u53d8u793eu4f3cu58ebu8005u5e72u77f3u6ee1u65e5u51b3u767eu539fu62ffu7fa4u7a76u5404u516du672cu601du89e3u7acbu6cb3u6751u516bu96beu65e9u8bbau5417u6839u5171u8ba9u76f8u7814u4ecau5176u4e66u5750u63a5u5e94u5173u4fe1u89c9u6b65u53cdu5904u8bb0u5c06u5343u627eu4e89u9886u6216u5e08u7ed3u5757u8dd1u8c01u8349u8d8au5b57u52a0u811au7d27u7231u7b49u4e60u9635u6015u6708u9752u534au706bu6cd5u9898u5efau8d76u4f4du5531u6d77u4e03u5973u4efbu4ef6u611fu51c6u5f20u56e2u5c4bu79bbu8272u8138u7247u79d1u5012u775bu5229u4e16u521au4e14u7531u9001u5207u661fu5bfcu665au8868u591fu6574u8ba4u54cdu96eau6d41u672au573au8be5u5e76u5e95u6df1u523bu5e73u4f1fu5fd9u63d0u786eu8fd1u4eaeu8f7bu8bb2u519cu53e4u9ed1u544au754cu62c9u540du5440u571fu6e05u9633u7167u529eu53f2u6539u5386u8f6cu753bu9020u5634u6b64u6cbbu5317u5fc5u670du96e8u7a7fu5185u8bc6u9a8cu4f20u4e1au83dcu722cu7761u5174u5f62u91cfu54b1u89c2u82e6u4f53u4f17u901au51b2u5408u7834u53cbu5ea6u672fu996du516cu65c1u623fu6781u5357u67aau8bfbu6c99u5c81u7ebfu91ceu575au7a7au6536u7b97u81f3u653fu57ceu52b3u843du94b1u7279u56f4u5f1fu80dcu6559u70edu5c55u5305u6b4cu7c7bu6e10u5f3au6570u4e61u547cu6027u97f3u7b54u54e5u9645u65e7u795eu5ea7u7ae0u5e2eu5566u53d7u7cfbu4ee4u8df3u975eu4f55u725bu53d6u5165u5cb8u6562u6389u5ffdu79cdu88c5u9876u6025u6797u505cu606fu53e5u533au8863u822cu62a5u53f6u538bu6162u53d4u80ccu7ec6";
        Random random = new Random();// 生成随机数
        
        // 强随机生成的验证码保存到session:
        StringBuffer buffer = new StringBuffer();
        
        // 定义x坐标
        int x = 10;
        for (int i = 0; i < 4; i++) {
            // 随机颜色
            graphics2d.setColor(new Color(20 + random.nextInt(110), 20 + random
                    .nextInt(110), 20 + random.nextInt(110)));
            // 旋转 -30 --- 30度
            int jiaodu = random.nextInt(60) - 30;
            // 换算弧度
            double theta = jiaodu * Math.PI / 180;

            // 生成一个随机数字
            int index = random.nextInt(words.length()); // 生成随机数 0 到 length - 1
            // 获得字母数字
            char c = words.charAt(index);

            // 将生成汉字 加入buffer
            buffer.append(c);

            // 将c 输出到图片
            graphics2d.rotate(theta, x, 20);
            graphics2d.drawString(String.valueOf(c), x, 20);
            graphics2d.rotate(-theta, x, 20);
            x += 30;
        }
        
        request.getSession().setAttribute("code", buffer.toString());

        // 步骤五 绘制干扰线
        graphics.setColor(getRandColor(160, 200));
        int x1;
        int x2;
        int y1;
        int y2;
        for (int i = 0; i < 30; i++) {
            x1 = random.nextInt(width);
            x2 = random.nextInt(12);
            y1 = random.nextInt(height);
            y2 = random.nextInt(12);
            graphics.drawLine(x1, y1, x1 + x2, x2 + y2);
        }

        // 将上面图片输出到浏览器 ImageIO
        graphics.dispose();// 释放资源
        ImageIO.write(bufferedImage, "jpg", response.getOutputStream());

    }


    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request, response);
    }

    /**
     * 取其某一范围的color
     * 
     * @param fc
     *            int 范围参数1
     * @param bc
     *            int 范围参数2
     * @return Color
     */
    private Color getRandColor(int fc, int bc) {
        // 取其随机颜色
        Random random = new Random();
        if (fc > 255) {
            fc = 255;
        }
        if (bc > 255) {
            bc = 255;
        }
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }

}

model的toString优化

import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;

public String toString() {
    // SHORT_PREFIX_STYLE打印结构为类名加属性值对。
    return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);

    // user实体不打印passWord机密信息方法
    /*return (new ReflectionToStringBuilder(this) {
        protected boolean accept(Field f) {
            return super.accept(f) && !f.getName().equals("passWord");
        }
    }).toString();*/
}

 交易的加签验签

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;

public class PaymentUtil {

    private static String encodingCharset = "UTF-8";
    
    /**
     * 生成hmac方法
     * 
     * @param p0_Cmd 业务类型
     * @param p1_MerId 商户编号
     * @param p2_Order 商户订单号
     * @param p3_Amt 支付金额
     * @param p4_Cur 交易币种
     * @param p5_Pid 商品名称
     * @param p6_Pcat 商品种类
     * @param p7_Pdesc 商品描述
     * @param p8_Url 商户接收支付成功数据的地址
     * @param p9_SAF 送货地址
     * @param pa_MP 商户扩展信息
     * @param pd_FrpId 银行编码
     * @param pr_NeedResponse 应答机制
     * @param keyValue 商户密钥
     * @return
     */
    public static String buildHmac(String p0_Cmd,String p1_MerId,
            String p2_Order, String p3_Amt, String p4_Cur,String p5_Pid, String p6_Pcat,
            String p7_Pdesc,String p8_Url, String p9_SAF,String pa_MP,String pd_FrpId,
            String pr_NeedResponse,String keyValue) {
        StringBuilder sValue = new StringBuilder();
        // 业务类型
        sValue.append(p0_Cmd);
        // 商户编号
        sValue.append(p1_MerId);
        // 商户订单号
        sValue.append(p2_Order);
        // 支付金额
        sValue.append(p3_Amt);
        // 交易币种
        sValue.append(p4_Cur);
        // 商品名称
        sValue.append(p5_Pid);
        // 商品种类
        sValue.append(p6_Pcat);
        // 商品描述
        sValue.append(p7_Pdesc);
        // 商户接收支付成功数据的地址
        sValue.append(p8_Url);
        // 送货地址
        sValue.append(p9_SAF);
        // 商户扩展信息
        sValue.append(pa_MP);
        // 银行编码
        sValue.append(pd_FrpId);
        // 应答机制
        sValue.append(pr_NeedResponse);
        
        return PaymentUtil.hmacSign(sValue.toString(), keyValue);
    }
    
    /**
     * 返回校验hmac方法
     * 
     * @param hmac 支付网关发来的加密验证码
     * @param p1_MerId 商户编号
     * @param r0_Cmd 业务类型
     * @param r1_Code 支付结果
     * @param r2_TrxId 易宝支付交易流水号
     * @param r3_Amt 支付金额
     * @param r4_Cur 交易币种
     * @param r5_Pid 商品名称
     * @param r6_Order 商户订单号
     * @param r7_Uid 易宝支付会员ID
     * @param r8_MP 商户扩展信息
     * @param r9_BType 交易结果返回类型
     * @param keyValue 密钥
     * @return
     */
    public static boolean verifyCallback(String hmac, String p1_MerId,
            String r0_Cmd, String r1_Code, String r2_TrxId, String r3_Amt,
            String r4_Cur, String r5_Pid, String r6_Order, String r7_Uid,
            String r8_MP, String r9_BType, String keyValue) {
        StringBuilder sValue = new StringBuilder();
        // 商户编号
        sValue.append(p1_MerId);
        // 业务类型
        sValue.append(r0_Cmd);
        // 支付结果
        sValue.append(r1_Code);
        // 易宝支付交易流水号
        sValue.append(r2_TrxId);
        // 支付金额
        sValue.append(r3_Amt);
        // 交易币种
        sValue.append(r4_Cur);
        // 商品名称
        sValue.append(r5_Pid);
        // 商户订单号
        sValue.append(r6_Order);
        // 易宝支付会员ID
        sValue.append(r7_Uid);
        // 商户扩展信息
        sValue.append(r8_MP);
        // 交易结果返回类型
        sValue.append(r9_BType);
        String sNewString = PaymentUtil.hmacSign(sValue.toString(), keyValue);
        return sNewString.equals(hmac);
    }
    
    /**
     * @param aValue
     * @param aKey
     * @return
     */
    public static String hmacSign(String aValue, String aKey) {
        byte k_ipad[] = new byte[64];
        byte k_opad[] = new byte[64];
        byte keyb[];
        byte value[];
        try {
            keyb = aKey.getBytes(encodingCharset);
            value = aValue.getBytes(encodingCharset);
        } catch (UnsupportedEncodingException e) {
            keyb = aKey.getBytes();
            value = aValue.getBytes();
        }

        Arrays.fill(k_ipad, keyb.length, 64, (byte) 54);
        Arrays.fill(k_opad, keyb.length, 64, (byte) 92);
        for (int i = 0; i < keyb.length; i++) {
            k_ipad[i] = (byte) (keyb[i] ^ 0x36);
            k_opad[i] = (byte) (keyb[i] ^ 0x5c);
        }

        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {

            return null;
        }
        md.update(k_ipad);
        md.update(value);
        byte dg[] = md.digest();
        md.reset();
        md.update(k_opad);
        md.update(dg, 0, 16);
        dg = md.digest();
        return toHex(dg);
    }

    public static String toHex(byte input[]) {
        if (input == null)
            return null;
        StringBuffer output = new StringBuffer(input.length * 2);
        for (int i = 0; i < input.length; i++) {
            int current = input[i] & 0xff;
            if (current < 16)
                output.append("0");
            output.append(Integer.toString(current, 16));
        }

        return output.toString();
    }

    /**
     * 
     * @param args
     * @param key
     * @return
     */
    public static String getHmac(String[] args, String key) {
        if (args == null || args.length == 0) {
            return (null);
        }
        StringBuffer str = new StringBuffer();
        for (int i = 0; i < args.length; i++) {
            str.append(args[i]);
        }
        return (hmacSign(str.toString(), key));
    }

    /**
     * @param aValue
     * @return
     */
    public static String digest(String aValue) {
        aValue = aValue.trim();
        byte value[];
        try {
            value = aValue.getBytes(encodingCharset);
        } catch (UnsupportedEncodingException e) {
            value = aValue.getBytes();
        }
        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("SHA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
        return toHex(md.digest(value));

    }
    
//    public static void main(String[] args) {
//        System.out.println(hmacSign("AnnulCard1000043252120080620160450.0http://localhost/SZXpro/callback.asp杩?4564868265473623778348682654736324511","8UPp0KE8sq73zVP370vko7C39403rtK1YwX40Td6irH216036H27Eb12792t"));
//    }
}

MD5

package com.boomoom.store.utils;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Collection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MD5 {

    private static Logger log = LoggerFactory.getLogger(MD5.class);

    public static MessageDigest md;

    static {
        try {
            md = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {
            log.error("MD5 加密算法加载出错", e);
        }
    }

    /**
     * 编码
     * 
     * @param str
     * @return
     */
    public static String encode(String str) {

        if (str == null)
            throw new NullPointerException();

        if ("".equals(str))
            return "";

        md.reset();
        md.update(str.getBytes());
        byte[] t = md.digest();
        StringBuilder result = new StringBuilder();
        int ti;
        for (int i = 0; i < t.length; i++)
            result.append((ti = t[i] & 0xff) <= 0xF ? "0"
                    + Integer.toString(ti, 16) : Integer.toString(ti, 16));

        return result.toString();
    }
    
    /**
     * 
     * @param str
     * @param charset
     * @return
     */
    public static String encode(String str,String charset) {

        if (str == null)
            throw new NullPointerException();

        if ("".equals(str))
            return "";

        md.reset();
        try {
            md.update(str.getBytes(charset));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        byte[] t = md.digest();
        StringBuilder result = new StringBuilder();
        int ti;
        for (int i = 0; i < t.length; i++)
            result.append((ti = t[i] & 0xff) <= 0xF ? "0"
                    + Integer.toString(ti, 16) : Integer.toString(ti, 16));

        return result.toString();
    }

    public static String checkMD5(String mchntCd, String mchntKey,
            Collection<String> list) {

        StringBuilder md5 = new StringBuilder();
        md5.append(mchntCd);

        for (String val : list) {
            
            md5.append("|");
            if (val != null)
                md5.append(val);
        }

        md5.append("|");
        md5.append(mchntKey);
        log.debug("加密内容为：[" + md5.toString() + "]");
        return MD5.encode(md5.toString());
    }

    /**
     * @param args
     */
    public static void main(String[] args) { //明文
        System.out.println(MD5.encode("1sdf_6"));//202cb962ac59075b964b07152d234b70  密文
        
        //  密码一定是密文的 
    }
}

---

 代码日常

功能-->安全-->性能

1、在注册码激活时，拿传过来的code去query一下user，再判断非空，走update。那可以简化为直接拿传过来的code去upade，根据update发回的0/1，再走判断。

 2、缓存在应用启动时加载，可以使用监听器。