国产探花免费观看_亚洲丰满少妇自慰呻吟_97日韩有码在线_资源在线日韩欧美_一区二区精品毛片,辰东完美世界有声小说,欢乐颂第一季,yy玄幻小说排行榜完本

首頁 > 開發 > Java > 正文

Spring Boot設置并使用緩存的步驟

2024-07-14 08:43:34
字體:
來源:轉載
供稿:網友

幾個緩存注解的作用:

@Cacheable:將方法的返回結果根據key指定的鍵保存在緩存中,以后要獲取相同的數據直接從緩存中共獲取

  • cacheNames/value:指定Cache組件名稱
  • key:指定緩存時使用的key,默認使用方法參數值,可以使用#a0、#p0、#參數名等,支持SpEL表達式,root可省略
  • keyGenerator:指定key的生成器的組件id,如自定義的KeyGenerator
  • cacheManager:指定緩存管理器
  • cacheResolver:指定緩存解析器
  • condition:指定在哪種條件下緩存,如condition = “#id>=1”在參數>=1時緩存
  • unless:指定該條件為真時不緩存
  • sync:指定是否使用異步模式

@CachePut:不管緩存中是否有需要的數據,都會執行該注解標注的方法,并將結果更新到緩存,屬性見上

@CacheEvit:執行方法后,清除key指定的緩存

  • allEntries:默認為false,值為true,刪除所有緩存
  • beforeInvocation:默認為false,值為true,在方法調用之前清除緩存

@CacheConfig:定義一些通用或公共的規則,如cacheNames、keyGenerator等

可使用的SpEL表達式:

Spring,Boot,緩存

使用緩存的步驟:

(1)創建一個Spring Boot應用,勾選Cache、Web、MySQL、Mybatis模塊,在主程序類上添加注解,開啟基于注解的緩存

@MapperScan(basePackages = "com.youngpain.cache.mapper")@SpringBootApplication@EnableCaching

(2)創建JavaBean,和數據庫中的表對應,并配置數據源

spring: datasource:  url: jdbc:mysql://localhost:3306/mybatis_database  username: root  password: 1741248769  driver-class-name: com.mysql.jdbc.Driver redis:  host: 39.108.114.57#開啟駝峰命名法mybatis: configuration:  map-underscore-to-camel-case: truelogging: level:  com.youngpain.cache.mapper: debug

(3)創建mapper接口進行增刪改查操作

/** * 部門表的增刪改查操作 */public interface DepartmentMapper {  @Insert("insert into department(id,depart_name,depart_build) values(#{id},#{depart_name},#{depart_build})")  void insertDepartment(Department department);  @Delete("delete from department where id=#{id}")  void deleteDepartment(Integer id);  @Update("update department set depart_name=#{departName},depart_build=#{departBuild} where id=#{id}")  void updateDepartment(Department department);  @Select("select * from department where id=#{id}")  Department getDepartmentById(Integer id);}

(4)創建service

@Service@CacheConfig(cacheNames = {"departs"})public class DepartmentService {  @Autowired  DepartmentMapper departmentMapper;  @Cacheable(key = "#a0.id")  public void insertDepartment(Department department) {    departmentMapper.insertDepartment(department);  }  @CacheEvict(key = "#p0")  public void deleteDepartment(Integer id) {    departmentMapper.deleteDepartment(id);  }  @CachePut(key = "#a0.id")  public Department updateDepartment(Department department) {    departmentMapper.updateDepartment(department);    return department;  }  @Cacheable(key = "#id", condition = "#p0>=1")  public Department getDepartmentById(Integer id) {    return departmentMapper.getDepartmentById(id);  }}

(5)創建controller

@Controllerpublic class DepartmentController {  @Autowired  DepartmentService departmentService;  @GetMapping("/index")  public String index() {    return "index";  }  @GetMapping("/deleteDepart/{id}")  public String deleteDepart(@PathVariable("id") Integer id, Model model) {    model.addAttribute("condition", "delete");    Department delete = departmentService.getDepartmentById(id);    model.addAttribute("department", delete);    departmentService.deleteDepartment(id);    return "success";  }  @PostMapping("/updateDepart")  public String updateDepart(Department department, Model model) {    model.addAttribute("condition", "update");    Department update = departmentService.updateDepartment(department);    model.addAttribute("department", update);    return "success";  }  @GetMapping("/getDepart/{id}")  public String getDepartmentById(@PathVariable("id") Integer id, Model model) {    model.addAttribute("condition", "delete");    Department get = departmentService.getDepartmentById(id);    model.addAttribute("department", get);    return "success";  }}

(6)測試結果:

@Cacheable:第一次查詢數據,控制臺發出sql語句,之后再查詢直接從緩存中獲取
@CachePut:調用方法修改某個數據后,再次查詢該數據是從緩存中獲取的更新后的數據
@CacheEvict:調用該方法后,再次查詢某個數據需要重新發出sql語句查詢

ps:之前只是用markdown記筆記,今天第一次用markdown寫文章,寫起來好舒服啊QAQ

總結

以上就是這篇文章的全部內容了,希望本文的內容對大家的學習或者工作具有一定的參考學習價值,謝謝大家對VeVb武林網的支持。


注:相關教程知識閱讀請移步到JAVA教程頻道。
發表評論 共有條評論
用戶名: 密碼:
驗證碼: 匿名發表
主站蜘蛛池模板: 宝坻区| 孝昌县| 普兰县| 梧州市| 嘉善县| 广昌县| 岐山县| 桃源县| 柘荣县| 正安县| 垫江县| 收藏| 凤阳县| 怀来县| 库尔勒市| 简阳市| 西乡县| 隆德县| 涿州市| 互助| 泽普县| 南阳市| 遂昌县| 汽车| 东城区| 康马县| 铁力市| 大宁县| 玛曲县| 弋阳县| 内江市| 清水河县| 祁东县| 辰溪县| 疏勒县| 石首市| 定陶县| 乌兰浩特市| 潍坊市| 隆子县| 循化|