完成学习事务

user-service/src/main/java/cn/mayiming/App.java

@@ -4,6 +4,7 @@ package cn.mayiming;
 import org.mybatis.spring.annotation.MapperScan;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
 
 /**
  * Hello world!
@@ -12,6 +13,7 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
 
 @SpringBootApplication
 @MapperScan("cn.mayiming.Mapper")
+@EnableTransactionManagement
 public class App 
 {
     public static void main( String[] args )

user-service/src/main/java/cn/mayiming/Controller/UserController.java

@@ -4,18 +4,26 @@ import cn.mayiming.Mapper.UserMapper;
 import cn.mayiming.Service.UserService;
 import cn.mayiming.entity.User;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.web.bind.annotation.PostMapping;
-import org.springframework.web.bind.annotation.RequestBody;
-import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.*;
 
 @RestController
 public class UserController {
 
     @Autowired
-    private UserMapper userMapper;
+    private UserService userService;
 
     @PostMapping("/user")
     public User getUser(@RequestBody User user) {
-        return userMapper.selectByUsername(user.getUsername());
+        return userService.getUserByUsername(user.getUsername());
+    }
+
+    @PutMapping("/user")
+    public int updateUser(@RequestBody User user) {
+        return userService.updateUser(user);
+    }
+
+    @GetMapping("/user")
+    public User GetUserByid(@RequestParam Integer id) {
+        return userService.getUserById(id);
     }
 }

user-service/src/main/java/cn/mayiming/Mapper/UserMapper.java

@@ -40,11 +40,17 @@ public interface UserMapper {
      * @param user 用户对象（含要更新的字段）
      * @return 影响行数
      */
-    @Update("UPDATE user SET " +
-            "username = #{username}, " +
-            "password = #{password}, " +
-            "nickname = #{nickname} " +
-            "WHERE id = #{id}")
+    @Update({
+            "<script>",
+            "UPDATE user",
+            "<set>",
+            "   <if test='username != null'>username = #{username},</if>",
+            "   <if test='password != null'>password = #{password},</if>",
+            "   <if test='nickname != null'>nickname = #{nickname}</if>",
+            "</set>",
+            "WHERE id = #{id}",
+            "</script>"
+    })
     int updateById(User user);
 
     /**

user-service/src/main/java/cn/mayiming/Service/UserService.java

@@ -2,8 +2,10 @@ package cn.mayiming.Service;
 
 import cn.mayiming.Mapper.UserMapper;
 import cn.mayiming.entity.User;
+import org.apache.ibatis.jdbc.Null;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
 import java.util.List;
 
@@ -21,6 +23,7 @@ public class UserService {
         return rows;
     }
 
+
     // 根据用户名查询
     public User getUserByUsername(String username) {
         return userMapper.selectByUsername(username);
@@ -30,4 +33,16 @@ public class UserService {
     public List<User> getAllUsers() {
         return userMapper.selectAll();
     }
+
+    public User getUserById(Integer id) {
+        return userMapper.selectById(id);
+    }
+
+    @Transactional(rollbackFor = Exception.class)
+    public int updateUser(User user) {
+        if (user.getId() == null){
+            throw new IllegalArgumentException("更新失败：用户ID不能为空");
+        }
+        return userMapper.updateById(user);
+    }
 }

user-service/src/main/java/cn/mayiming/entity/User.java

@@ -19,4 +19,24 @@ public class User {
 
     String username;
     String password;
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    Integer id;
+
+    public String getNickname() {
+        return nickname;
+    }
+
+    public void setNickname(String nickname) {
+        this.nickname = nickname;
+    }
+
+    String nickname;
 }