diff --git a/document/src/main/java/com/haihang/controller/CaseController.java b/document/src/main/java/com/haihang/controller/CaseController.java
new file mode 100644
index 0000000..d29d4fb
--- /dev/null
+++ b/document/src/main/java/com/haihang/controller/CaseController.java
@@ -0,0 +1,44 @@
+package com.haihang.controller;
+
+
+import com.haihang.entity.Case;
+import com.haihang.service.CaseService;
+import com.haihang.utils.Result;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+@RequestMapping("/case")
+public class CaseController {
+    //用例相关接口
+
+    @Autowired
+    private CaseService caseService;
+
+    @PostMapping("/add")
+    public Result add(@RequestBody Case _case){
+
+        return caseService.add(_case);
+    }
+
+
+    @DeleteMapping("/{id}")
+    public Result delete(@PathVariable int id){
+        //根据id删除用例，删除一个用例他的子用例会一并全部删除
+        return caseService.deleteWithSonById(id);
+    }
+
+    @PutMapping("update")
+    public Result update(@RequestBody Case _case){
+        //修改用例，只能修改用例名字和用例描述
+        return caseService.update(_case);
+    }
+
+    @GetMapping("/{id}")
+    public Result get(@PathVariable int id){
+        //根据id查询用例信息接口
+        return caseService.getById(id);
+
+    }
+
+}
diff --git a/document/src/main/java/com/haihang/entity/Case.java b/document/src/main/java/com/haihang/entity/Case.java
new file mode 100644
index 0000000..da6de14
--- /dev/null
+++ b/document/src/main/java/com/haihang/entity/Case.java
@@ -0,0 +1,24 @@
+package com.haihang.entity;
+
+import lombok.Data;
+import org.apache.ibatis.annotations.Insert;
+
+import java.util.Date;
+
+//用例信息，与数据库完全相同
+@Data
+public class Case {
+
+    private int     id;
+    private String      caseName;
+    private int     parentId;
+    private int     isLeaf;
+    private int     createUser;
+    private int     updateUser;
+    private Date createTime;
+    private Date    updateTime;
+    private String caseDesc;//用例描述
+
+
+
+}
diff --git a/document/src/main/java/com/haihang/mapper/CaseMapper.java b/document/src/main/java/com/haihang/mapper/CaseMapper.java
new file mode 100644
index 0000000..3ce1f0e
--- /dev/null
+++ b/document/src/main/java/com/haihang/mapper/CaseMapper.java
@@ -0,0 +1,33 @@
+package com.haihang.mapper;
+
+import com.haihang.entity.Case;
+import org.apache.ibatis.annotations.*;
+
+import java.util.List;
+
+@Mapper
+public interface CaseMapper {
+
+    @Select("select * from case_table where id = #{parentId}")
+    Case selectById(int parentId);
+
+    @Insert("INSERT INTO `case_table`\n" +
+            "(id, case_name, parent_id, is_leaf, create_user, update_user, create_time, update_time, case_desc)\n" +
+            "VALUES(null, #{caseName}, #{parentId}, 1, #{createUser}, #{updateUser}, #{createTime}, #{updateTime}, #{caseDesc});")
+    void insert(Case aCase);
+
+    @Update("update case_table set is_leaf = #{isLeaf},case_name =  #{caseName},parent_id =  #{parentId}" +
+            ", update_user = #{updateUser},update_time = null ,case_desc=#{caseDesc} " +
+            "where id = #{id}")
+    void update(Case parentCase);
+
+
+    @Delete("delete from case_table where id = #{id}")
+    void deleteById(int id);
+
+    @Select("select id from case_table where parent_id =#{id}")
+    List<Integer> selectByParentId(int id);
+
+    @Update("update case_table set is_leaf = #{i} where id =#{parentId}")
+    void updateIsLeaf(int i, int parentId);
+}
diff --git a/document/src/main/java/com/haihang/service/CaseService.java b/document/src/main/java/com/haihang/service/CaseService.java
new file mode 100644
index 0000000..326c70d
--- /dev/null
+++ b/document/src/main/java/com/haihang/service/CaseService.java
@@ -0,0 +1,16 @@
+package com.haihang.service;
+
+import com.haihang.entity.Case;
+import com.haihang.utils.Result;
+
+public interface CaseService {
+
+
+    Result add(Case aCase);
+
+    Result deleteWithSonById(int id);
+
+    Result update(Case aCase);
+
+    Result getById(int id);
+}
diff --git a/document/src/main/java/com/haihang/service/impl/CaseServiceImpl.java b/document/src/main/java/com/haihang/service/impl/CaseServiceImpl.java
new file mode 100644
index 0000000..853c87c
--- /dev/null
+++ b/document/src/main/java/com/haihang/service/impl/CaseServiceImpl.java
@@ -0,0 +1,98 @@
+package com.haihang.service.impl;
+
+import com.haihang.entity.Case;
+import com.haihang.mapper.CaseMapper;
+import com.haihang.service.CaseService;
+import com.haihang.utils.Result;
+import com.haihang.utils.UserHolder;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import java.util.Date;
+import java.util.List;
+
+@Service
+public class CaseServiceImpl implements CaseService {
+
+
+    @Autowired
+    private CaseMapper caseMapper;
+
+
+    //新增用例
+    @Override
+    public Result add(Case aCase) {
+        aCase.setCreateTime(new Date());
+        aCase.setUpdateTime(new Date());
+
+        //判断传进来的用例父节点id，查询他是不是叶子节点，如果不是叶子节点则不能新增用例
+        int parentId = aCase.getParentId();
+        if(parentId == 0){
+            //如果父节点为空，说明还没建立树，可以直接插入
+            caseMapper.insert(aCase);
+
+            return Result.ok();
+        }
+        Case parentCase =  caseMapper.selectById(parentId);
+        int isLeaf = parentCase.getIsLeaf();
+        if(isLeaf!=1){
+            return Result.fail("该用例不能添加！原因：父节点并非叶子节点");
+        }
+        aCase.setCreateUser(UserHolder.getUser().getId());
+        aCase.setUpdateUser(UserHolder.getUser().getId());
+
+        caseMapper.insert(aCase);
+        //插入完成要把父亲的isleaf修改掉.
+        parentCase.setIsLeaf(0);
+        caseMapper.update(parentCase);
+        return Result.ok();
+    }
+
+    @Override
+    public Result deleteWithSonById(int id) {
+        //先根据id查询
+        Case aCase = caseMapper.selectById(id);
+        if(aCase==null){
+            return Result.ok();
+        }
+        //根据当前id查询父节点为id的id列表，找他的儿子们
+        List<Integer> ids= caseMapper.selectByParentId(id);
+
+        //删他的儿子们
+        for(Integer sonId:ids){
+            deleteWithSonById(sonId);
+        }
+
+        //在删除自己之前顺便记录parentId
+        int parentId = aCase.getParentId();
+
+        //有值则删除自己
+        caseMapper.deleteById(id);
+
+        //根据他爹id判断他爹isleaf
+        List<Integer> brotherId= caseMapper.selectByParentId(parentId);
+        if(brotherId == null || brotherId.isEmpty()){
+            caseMapper.updateIsLeaf(1,parentId);
+        }
+        return Result.ok();
+    }
+
+    @Override
+    public Result update(Case aCase) {
+        Case dbCase = caseMapper.selectById(aCase.getId());
+        dbCase.setCaseName(aCase.getCaseName());
+        dbCase.setCaseDesc(aCase.getCaseDesc());
+        dbCase.setUpdateUser(UserHolder.getUser().getId());
+        dbCase.setUpdateTime(new Date());
+        caseMapper.update(dbCase);
+        return Result.ok();
+    }
+
+    @Override
+    public Result getById(int id) {
+        Case aCase = caseMapper.selectById(id);
+        return Result.ok(aCase);
+    }
+
+
+}
diff --git a/document/src/main/java/com/haihang/utils/LoginInterceptor.java b/document/src/main/java/com/haihang/utils/LoginInterceptor.java
index c60d387..a2c6024 100644
--- a/document/src/main/java/com/haihang/utils/LoginInterceptor.java
+++ b/document/src/main/java/com/haihang/utils/LoginInterceptor.java
@@ -5,6 +5,7 @@ package com.haihang.utils;
 
 import cn.hutool.core.bean.BeanUtil;
 import com.baomidou.mybatisplus.core.toolkit.StringUtils;
+import com.haihang.entity.UserInfo;
 import org.springframework.data.redis.core.StringRedisTemplate;
 import org.springframework.web.servlet.HandlerInterceptor;
 
@@ -53,6 +54,12 @@ public class LoginInterceptor implements HandlerInterceptor {
 //        //hash转UserDTO存入ThreadLocal
 //        UserHolder.saveUser(BeanUtil.fillBeanWithMap(userMap, new UserDTO(), false));
         //走到这里说明前端传过来的token里面有值且是登录用户，放行就完事了，暂时不用ThreadLocal
+
+        //将用户id存放到ThreadLocal
+        UserHolder.saveUser(BeanUtil.fillBeanWithMap(userMap, new UserInfo(), false));
+
+
+
         return true;
     }
 
diff --git a/document/src/main/java/com/haihang/utils/UserHolder.java b/document/src/main/java/com/haihang/utils/UserHolder.java
new file mode 100644
index 0000000..702fadc
--- /dev/null
+++ b/document/src/main/java/com/haihang/utils/UserHolder.java
@@ -0,0 +1,20 @@
+package com.haihang.utils;
+
+import com.haihang.entity.UserDTO;
+import com.haihang.entity.UserInfo;
+
+public class UserHolder {
+    private static final ThreadLocal<UserInfo> tl = new ThreadLocal<>();
+
+    public static void saveUser(UserInfo user){
+        tl.set(user);
+    }
+
+    public static UserInfo getUser(){
+        return tl.get();
+    }
+
+    public static void removeUser(){
+        tl.remove();
+    }
+}