springboot

文章目录

定时任务mybatis基于注解开发mybatis-plus实体类用到的注解crud测试自定义配置类，配置分页插件及乐观锁插件逆向工程分页插件使用

定时任务

玩转SpringBoot之定时任务详解（定时表达式持久化、多线程执行定时任务）

springboot内部集成，不需要引入jar包，不需要配置。定时任务使用务必存进redis或mysql，以防服务器挂掉定时任务丢失。使用（基本同spring）：在Application.java添加注解 @EnableScheduling 编写定时任务 @Component public class ScheduleService { @Scheduled(cron = "*/5 15 18 * * ?") public void scheduledTest(){ System.out.println("定时任务"); } }

mybatis基于注解开发

使用注解开发不需要xml文件，所以pom文件的resources不必再配置，yml文件的mapper-locations也不用再配置。别名和驼峰映射也不需要。mapper接口代码 public interface ApplySimpleMapper { @Delete("delete from aftersale_return_apply_simple where aras_id = #{arasId}") int deleteByPrimaryKey(Integer arasId); @Insert("<script>" + "insert into aftersale_return_apply_simple" + "<trim prefix='(' suffix=')' suffixOverrides=','>" + "<if test='arasName != null'>aras_name,</if>" + "<if test='arasOrderId != null'>aras_order_id,</if>" + "</trim>" + "<trim prefix='values (' suffix=')' suffixOverrides=','>" + "<if test='arasName != null'>#{arasName},</if>" + "<if test='arasOrderId != null'>#{arasOrderId},</if>" + "</trim>" + "</script>") @Options(useGeneratedKeys = true, keyProperty = "arasId") int insertSelective(ApplySimple record); @Select("select * from aftersale_return_apply_simple where aras_id = #{arasId}") ApplySimple selectByPrimaryKey(Integer arasId); @Select("<script>" + "select * from aftersale_return_apply_simple" + "<where>" + "<if test='arasName != null'>and aras_name = #{arasName}</if>" + "<if test='arasOrderId != null'>and aras_order_id = #{arasOrderId}</if>" + "</where>" + "</script>") List<ApplySimple> selectByPrimaryKeyList(ApplySimple applySimple); @Update("<script>update aftersale_return_apply_simple" + "<set >" + "<if test='arasName != null'>aras_name = #{arasName},</if>" + "<if test='arasOrderId != null'>aras_order_id = #{arasOrderId},</if>" + "<if test='arasRecordName != null'>aras_record_name = #{arasRecordName},</if>" + "<if test='arasStatus != null'>aras_status = #{arasStatus},</if>" + "<if test='arasCreatetime != null'>aras_createtime = #{arasCreatetime},</if>" + "<if test='arasUpdatetime != null'>aras_updatetime = #{arasUpdatetime},</if>" + "</set>" + "where aras_id = #{arasId}" + "</script>") int updateByPrimaryKeySelective(ApplySimple record); }

mybatis-plus

MyBatis-Plus官方文档

引入mybatis-plus的pom，基于mybatis，所以不需要重复引入mybatis的pom。与pagehelper包冲突，排出冲突的jar包（pagehelper不需要就删掉） <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>1.2.13</version> <exclusions> <exclusion> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> </exclusion> <exclusion> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> </exclusion> </exclusions> </dependency> Application.java配置MapperScan @MapperScan("com.javasm.mapper") @EnableTransactionManagement 配置datasource spring: datasource: driver-class-name: com.mysql.cj.jdbc.Driver url: jdbc:mysql://192.168.14.241:3306/crm?characterEncoding=UTF8&useSSL=true&serverTimezone=Asia/Shanghai username: root password: root

实体类用到的注解

@TableName("test_mybatisplus") public class TestMybatisplus { @TableId(type = IdType.ASSIGN_ID) // 分布式唯一id，雪花算法 private Long tid; private String tname; private String tadd; private String tcreatetime; private String tupdatetime; @TableField(exist = false) // 非数据库字段 private String authControl; @Version // 乐观锁注解 private Integer tversion; }

crud测试

@SpringBootTest public class MyBatisPlusTest { @Resource private ApplySimpleMapper2 sm; @Test public void add(){ TestMybatisplus mp = new TestMybatisplus(); mp.setTname("测试"); int insert = sm.insert(mp); // mybatisplus会自动把当前插入对象在数据库中的id写回到该实体中 System.out.println(mp.getTid()); } @Test public void update(){ TestMybatisplus mp = new TestMybatisplus(); mp.setTid(123L); mp.setTname("测试9"); // 乐观锁插件配置之后，更新成功version会自增加一，version不一致更新返回值为0 mp.setTversion(1); //根据id进行更新，没有传值的属性就不会更新 int i = sm.updateById(mp); System.out.println(i); } @Test public void select(){ // 条件构造器 QueryWrapper wrapper = new QueryWrapper(); wrapper.between("tcreatetime","2020-08-20","2020-09-20"); wrapper.like("tname","测试"); List<TestMybatisplus> testMybatispluses = sm.selectList(wrapper); // Map<String, Object> map = new HashMap<>(); // map.put("tname","测试4"); // List<TestMybatisplus> testMybatispluses = sm.selectByMap(map); System.out.println(testMybatispluses); } }

自定义配置类，配置分页插件及乐观锁插件

@Configuration public class MyConfiguration { //Jackson中通过ObejctMapper对象的writeValueAsString // 由于分布式id过长，js会精度损失，将id转为string再序列化 @Bean ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) { ObjectMapper build = builder.createXmlMapper(false).build(); build.setSerializationInclusion(JsonInclude.Include.NON_NULL);//非空才序列化 SimpleModule module = new SimpleModule(); module.addSerializer(Long.class,ToStringSerializer.instance); module.addSerializer(long.class,ToStringSerializer.instance); build.registerModule(module); return build; } @Bean public MybatisPlusInterceptor mybatisPlusInterceptor() { MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor(); //分页拦截器 interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL)); //乐观锁拦截器 interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor()); return interceptor; } }

逆向工程

pom引入，使用freemarker模板引擎 <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-generator</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>org.freemarker</groupId> <artifactId>freemarker</artifactId> <version>2.3.30</version> </dependency> 生成代码使用官网模板，稍作修改即可。

分页插件使用

@RestController @RequestMapping("/generator") public class TestMybatisplusController { @Resource private ITestMybatisplusService ms; @GetMapping("mp") public ResponseEntity getmp(@RequestParam(defaultValue = "1") Integer pageNum, @RequestParam(defaultValue = "2")Integer pageSize){ IPage<MP> page = new Page<>(pageNum,pageSize); IPage<MP> page1 = ms.page(page); return ResponseEntity.ok(page1); } }