version 0.3.1 update

修复多用户同时注册时可能造成用户名重复的bug；新增UserDao的SpringJDBC模板类实现

README.md

@@ -13,9 +13,10 @@
     <li>未经许可不得将本项目商用，如需商用请联系作者<a href="mailto:[email protected]">[email protected]</a></li>
 </ul>
 <h2>关键技术</h2>
-<p>基于SSM框架开发</p>
+<p>基于SSM框架开发的商城系统，代码严格遵循MVC分层思想，可部署到服务器上，设计精良，不断完善</p>
 <h3>前端</h3>
 <ul>
+    <li>前端对应View层</li>
     <li>前端使用jsp页面展示，并通过EL表达式接收服务器打给浏览器的数据</li>
     <li>使用js实现网页动态效果，通过jQuery简化操作，并配合html5实现前端的数据校验</li>
     <li>使用Ajax技术完成前端用户名可用性校验、退出登录功能</li>
@@ -152,6 +153,16 @@
         </td>
         <td>2020年9月25日</td>
     </tr>
+    <tr>
+        <td>0.3.1</td>
+        <td>
+            <ul>
+                <li>新增UserDao的SpringJDBC模板类实现</li>
+                <li>注册用户功能开启事务，修复多个用户同时注册时可能造成用户名重复的bug</li>
+            </ul>
+        </td>
+        <td>2020年9月29日</td>
+    </tr>
 </table>
 <h2>配置情况</h2>
 <ul>

src/applicationContext.xml

@@ -73,6 +73,9 @@
     </bean>
     <!--  开启注解事务管理-->
     <tx:annotation-driven/>
-
+    <!--  配置JDBC模板类  -->
+    <bean class="org.springframework.jdbc.core.JdbcTemplate" id="jdbcTemplate" >
+        <property name="dataSource" ref="dataSource" />
+    </bean>
 
 </beans>

src/com/supermarket/dao/UserDao.java

@@ -18,6 +18,13 @@ public interface UserDao {
      */
     public User queryUser(User user);
 
+    /**
+     * 查找好多用户
+     * @param user bean
+     * @return 用户组成的List
+     */
+    public List<? extends User> queryUsers(User user);
+
     /**
      * 用map查询用户
      *
@@ -26,6 +33,13 @@ public interface UserDao {
      */
     public User queryUser(Map<String, Object> map);
 
+    /**
+     * 查询很多用户
+     * @param map map
+     * @return 很多用户
+     */
+    public List<? extends User> queryUsers(Map<String, Object> map);
+
     /**
      * 插入用户
      *

src/com/supermarket/dao/UserJDBC.java

@@ -0,0 +1,109 @@
+package com.supermarket.dao;
+
+import com.supermarket.domain.User;
+import com.supermarket.domain.UserImpl;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.jdbc.core.BeanPropertyRowMapper;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+public class UserJDBC implements UserDao {
+    @Autowired
+    private JdbcTemplate jdbcTemplate = null;
+
+    @Override
+    public User queryUser(User user) {
+        List<? extends User> users = this.queryUsers(user);
+        if (users.isEmpty())
+            return null;
+        else
+            return users.get(0);
+    }
+
+    @Override
+    public List<? extends User> queryUsers(User user) {
+        if (user == null)
+            return new LinkedList<>();
+        String sql = "select * from user where 1 = 1";
+        List<Object> args = new LinkedList<Object>();
+        if (user.getId() != 0) {
+            sql = sql + " and id = ?";
+            args.add(user.getId());
+        }
+        if (user.getUsername() != null) {
+            sql = sql + " and username = ?";
+            args.add(user.getUsername());
+        }
+        if (user.getPassword() != null) {
+            sql = sql + " and password = ?";
+            args.add(user.getPassword());
+        }
+        if (user.getNickname() != null) {
+            sql = sql + " and nickname = ?";
+            args.add(user.getNickname());
+        }
+        if (user.getEmail() != null) {
+            sql = sql + " and email = ?";
+            args.add(user.getEmail());
+        }
+        List<? extends User> users = this.jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(UserImpl.class), args.toArray());
+        return users;
+    }
+
+    @Override
+    public User queryUser(Map<String, Object> map) {
+        List<? extends User> users = this.queryUsers(map);
+        if (users.isEmpty()){
+            return null;
+        }else {
+            return users.get(0);
+        }
+    }
+
+    @Override
+    public List<? extends User> queryUsers(Map<String, Object> map) {
+        if (map == null)
+            return new LinkedList<>();
+        String sql = "select * from user where 1 = 1";
+        List<Object> args = new LinkedList<Object>();
+        if (map.get("id") != null) {
+            sql = sql + " and id = ?";
+            args.add(map.get("id"));
+        }
+        if (map.get("username") != null) {
+            sql = sql + " and username = ?";
+            args.add(map.get("username"));
+        }
+        if (map.get("password") != null) {
+            sql = sql + " and password = ?";
+            args.add(map.get("password"));
+        }
+        if (map.get("nickname") != null) {
+            sql = sql + " and nickname = ?";
+            args.add(map.get("nickname"));
+        }
+        if (map.get("email") != null) {
+            sql = sql + " and email = ?";
+            args.add(map.get("email"));
+        }
+        List<? extends User> users = this.jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(UserImpl.class), args.toArray());
+        return users;
+    }
+
+    @Override
+    public void insertUser(User user) {
+        if (user == null)
+            return;
+        this.jdbcTemplate.update(
+                "insert into user (id, username, password, nickname, email) values (?, ?, ?, ?, ?)",
+                user.getId(),
+                user.getUsername(),
+                user.getPassword(),
+                user.getNickname(),
+                user.getEmail()
+        );
+    }
+}

src/com/supermarket/exception/MsgRollbackException.java

@@ -0,0 +1,12 @@
+package com.supermarket.exception;
+
+public class MsgRollbackException extends MsgException{
+    /**
+     * 韩餐构造方法
+     *
+     * @param message 在网页中的提示信息
+     */
+    public MsgRollbackException(String message) {
+        super(message);
+    }
+}

src/com/supermarket/mapper/UserMapper.xml

@@ -15,6 +15,17 @@
         </where>
     </select>
 
+    <select id="queryUsers" resultType="com.supermarket.domain.UserImpl">
+        select * from user
+        <where>
+            <if test="id != 0 and id != null">id = #{id}</if>
+            <if test="username != null">and username = #{username}</if>
+            <if test="password != null">and password = #{password}</if>
+            <if test="nickname != null">and nickname = #{nickname}</if>
+            <if test="email != null">and email = #{email}</if>
+        </where>
+    </select>
+
     <insert id="insertUser">
         insert into user
         <trim prefix="(" suffix=")" suffixOverrides=",">

src/com/supermarket/service/UserServiceImpl.java

@@ -4,6 +4,7 @@
 import com.supermarket.domain.User;
 import com.supermarket.domain.UserImpl;
 import com.supermarket.exception.MsgException;
+import com.supermarket.exception.MsgRollbackException;
 import com.supermarket.utils.WebUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
@@ -35,7 +36,7 @@ public User login(User user, String valistr, String valicode) throws MsgExceptio
             return user;
     }
 
-    @Transactional
+    @Transactional(rollbackOn = {RuntimeException.class, MsgRollbackException.class})
     @Override
     public User regist(
             @Valid User user,
@@ -63,13 +64,19 @@ public User regist(
             throw new MsgException("用户名已被注册");
         // 通过以上校验，插入数据
         this.userDao.insertUser(user);
+        // 检查数据库该用户名只有一个
+        Map<String, Object> map = new HashMap<String, Object>();
+        map.put("username", user.getUsername());
+        List<? extends User> users = this.userDao.queryUsers(map);
+        if (users.size() > 1)
+            throw new MsgRollbackException("用户名已被注册");
         return user;
     }
 
     @Override
     public boolean isUsernameAvailable(String username) {
         Map<String, Object> map = new HashMap<String, Object>();
         map.put("username", username);
-        return this.userDao.queryUser(map) == null;
+        return this.userDao.queryUsers(map).size() == 0;
     }
 }

web/WEB-INF/classes/applicationContext.xml

@@ -73,6 +73,9 @@
     </bean>
     <!--  开启注解事务管理-->
     <tx:annotation-driven/>
-
+    <!--  配置JDBC模板类  -->
+    <bean class="org.springframework.jdbc.core.JdbcTemplate" id="jdbcTemplate" >
+        <property name="dataSource" ref="dataSource" />
+    </bean>
 
 </beans>

web/WEB-INF/classes/com/supermarket/mapper/UserMapper.xml

@@ -15,6 +15,17 @@
         </where>
     </select>
 
+    <select id="queryUsers" resultType="com.supermarket.domain.UserImpl">
+        select * from user
+        <where>
+            <if test="id != 0 and id != null">id = #{id}</if>
+            <if test="username != null">and username = #{username}</if>
+            <if test="password != null">and password = #{password}</if>
+            <if test="nickname != null">and nickname = #{nickname}</if>
+            <if test="email != null">and email = #{email}</if>
+        </where>
+    </select>
+
     <insert id="insertUser">
         insert into user
         <trim prefix="(" suffix=")" suffixOverrides=",">